diff --git a/AGENTS.md b/AGENTS.md
index 6bfc8cdd6..f850aa3e5 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -60,8 +60,8 @@ rm -fR  package-lock.json node_modules && \
 
 ### Key Source Files
 
-- `src/app.ts` - `App` class extends MCP Protocol, handles guest initialization, tool calls, messaging
-- `src/app-bridge.ts` - `AppBridge` class for hosts, proxies MCP requests, sends tool input/results to guests
+- `src/app.ts` - `App` subclasses the base MCP SDK `Client`, handles View initialization, tool calls, and messaging
+- `src/app-bridge.ts` - `AppBridge` subclasses the base MCP SDK `Server` for the inner iframe channel and proxies through a separate outer `Client`
 - `src/server/index.ts` - Helpers for MCP servers to register tools/resources with UI metadata
 - `src/types.ts` - Protocol types re-exported from `spec.types.ts` and Zod schemas from `generated/schema.ts` (auto-generated during build)
 - `src/message-transport.ts` - `PostMessageTransport` for iframe communication
@@ -70,12 +70,12 @@ rm -fR  package-lock.json node_modules && \
 ### Protocol Flow
 
 ```
-View (App) <--PostMessageTransport--> Host (AppBridge) <--MCP Client--> MCP Server
+View (App/Client) <--PostMessageTransport--> Host (AppBridge/Server) <--separate MCP Client--> MCP Server
 ```
 
 1. Host creates iframe with view HTML
 2. View creates `App` instance and calls `connect()` with `PostMessageTransport`
-3. View sends `ui/initialize` request, receives host capabilities and context
+3. View and Host complete the temporary inner base MCP handshake, then the View sends `ui/initialize` and receives authoritative Apps capabilities and context
 4. Host sends `sendToolInput()` with tool arguments after initialization
 5. View can call server tools via `app.callServerTool()` or send messages via `app.sendMessage()`
 6. Host sends `sendToolResult()` when tool execution completes
diff --git a/README.md b/README.md
index 2fd89ffee..b3f68e77c 100644
--- a/README.md
+++ b/README.md
@@ -122,9 +122,17 @@ resources:
 ## Getting Started
 
 ```bash
-npm install -S @modelcontextprotocol/ext-apps
+npm install -S @modelcontextprotocol/ext-apps \
+  @modelcontextprotocol/client@2.0.0-beta.4 \
+  @modelcontextprotocol/server@2.0.0-beta.4 \
+  @modelcontextprotocol/core@2.0.0-beta.4 \
+  zod@^4.2.0
 ```
 
+This release uses the split base MCP SDK v2 packages. Install all three at the
+exact published beta.4 version so the Apps SDK and your MCP client/server share
+one compatible protocol implementation.
+
 **New here?** Start with the
 [Quickstart Guide](https://apps.extensions.modelcontextprotocol.io/api/documents/Quickstart.html)
 to build your first MCP App.
diff --git a/build.bun.ts b/build.bun.ts
index a129d5ddd..837279ff1 100644
--- a/build.bun.ts
+++ b/build.bun.ts
@@ -31,9 +31,15 @@ function buildJs(
   });
 }
 
-// zod is a peerDependency — keep it external so consumers share a single
-// zod instance (instanceof ZodError / schema.extend() break with duplicate copies).
-const PEER_EXTERNALS = ["@modelcontextprotocol/sdk", "zod"];
+// Peer dependencies stay external in the standard entry points so consumers
+// share one base MCP SDK and Zod instance. The *-with-deps entry points keep
+// bundling these dependencies for standalone browser use.
+const PEER_EXTERNALS = [
+  "@modelcontextprotocol/client",
+  "@modelcontextprotocol/core",
+  "@modelcontextprotocol/server",
+  "zod",
+];
 
 await Promise.all([
   buildJs("src/app.ts", {
diff --git a/docs/authorization.md b/docs/authorization.md
index 59fc26cde..df7adc6af 100644
--- a/docs/authorization.md
+++ b/docs/authorization.md
@@ -150,7 +150,7 @@ registerAppTool(
   "get_account_balance",
   {
     description: "Get account balance",
-    inputSchema: { accountId: z.string() },
+    inputSchema: z.object({ accountId: z.string() }),
   },
   async ({ accountId }) => {
     if (!authInfo) {
diff --git a/docs/migrate_from_openai_apps.md b/docs/migrate_from_openai_apps.md
index d91281b41..22d5d9f0c 100644
--- a/docs/migrate_from_openai_apps.md
+++ b/docs/migrate_from_openai_apps.md
@@ -66,7 +66,7 @@ The server-side changes involve updating metadata structure and using helper fun
 #### Before (OpenAI)
 
 ```typescript
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { McpServer } from "@modelcontextprotocol/server";
 import { z } from "zod";
 
 function createServer() {
@@ -78,7 +78,7 @@ function createServer() {
     {
       title: "Shopping Cart",
       description: "Display the user's shopping cart",
-      inputSchema: { userId: z.string() },
+      inputSchema: z.object({ userId: z.string() }),
       annotations: { readOnlyHint: true },
       _meta: {
         "openai/outputTemplate": "ui://view/cart.html",
@@ -126,7 +126,7 @@ function createServer() {
 #### After (MCP Apps)
 
 ```typescript
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { McpServer } from "@modelcontextprotocol/server";
 import {
   registerAppTool,
   registerAppResource,
@@ -144,7 +144,7 @@ function createServer() {
     {
       title: "Shopping Cart",
       description: "Display the user's shopping cart",
-      inputSchema: { userId: z.string() },
+      inputSchema: z.object({ userId: z.string() }),
       annotations: { readOnlyHint: true },
       _meta: { ui: { resourceUri: "ui://view/cart.html" } },
     },
diff --git a/docs/overview.md b/docs/overview.md
index 28f5b2379..317ab4300 100644
--- a/docs/overview.md
+++ b/docs/overview.md
@@ -56,7 +56,11 @@ flowchart LR
 - **Host** — The chat client (e.g., Claude Desktop) that connects to servers, embeds Views in iframes, and proxies communication between them.
 - **View** — The UI running inside a sandboxed iframe. It receives tool data from the Host and can call server tools or send messages back to the chat.
 
-The View acts as an MCP client, the Host acts as a proxy, and the Server is a standard MCP server.
+The View's `App` subclasses the base MCP SDK `Client`. The Host's `AppBridge`
+subclasses the base MCP SDK `Server` for the inner iframe channel, while a
+separate outer `Client` connects the Host to the actual MCP Server. Keeping
+those two connections separate prevents iframe negotiation and capabilities
+from leaking into the server connection.
 
 ## Lifecycle
 
@@ -93,7 +97,7 @@ sequenceDiagram
 ```
 
 1. **Discovery** — The Host learns about tools and their UI resources when connecting to the server.
-2. **Initialization** — When a UI tool is called, the Host renders the iframe. The View sends `ui/initialize` and receives host context (theme, capabilities, container dimensions). This handshake ensures the View is ready before receiving data.
+2. **Initialization** — When a UI tool is called, the Host renders the iframe. The SDK first completes its temporary inner base MCP handshake, then the View sends `ui/initialize` and receives host context (theme, capabilities, container dimensions). `ui/initialize` remains authoritative for Apps capabilities and identity, and `ui/notifications/initialized` remains the public View-ready signal.
 3. **Data delivery** — The Host sends tool arguments and, once available, tool results to the View. Results include both `content` (text for the model's context) and optionally `structuredContent` (data optimized for UI rendering). This separation lets servers provide rich data to the UI without bloating the model's context.
 4. **Interactive phase** — The user interacts with the View. The View can call tools, send messages, or update context.
 5. **Teardown** — Before unmounting, the Host notifies the View so it can save state or release resources.
diff --git a/docs/patterns.md b/docs/patterns.md
index 87a6d8232..884de2651 100644
--- a/docs/patterns.md
+++ b/docs/patterns.md
@@ -19,7 +19,7 @@ registerAppTool(
   "update-quantity",
   {
     description: "Update item quantity in cart",
-    inputSchema: { itemId: z.string(), quantity: z.number() },
+    inputSchema: z.object({ itemId: z.string(), quantity: z.number() }),
     _meta: {
       ui: {
         resourceUri: "ui://shop/cart.html",
@@ -127,14 +127,14 @@ registerAppTool(
   {
     title: "Read Data Bytes",
     description: "Load binary data in chunks",
-    inputSchema: {
+    inputSchema: z.object({
       id: z.string().describe("Resource identifier"),
       offset: z.number().min(0).default(0).describe("Byte offset"),
       byteCount: z
         .number()
         .default(MAX_CHUNK_BYTES)
         .describe("Bytes to read"),
-    },
+    }),
     outputSchema: DataChunkSchema,
     // Hidden from model - only callable by the App
     _meta: { ui: { visibility: ["app"] } },
@@ -281,10 +281,7 @@ server.registerResource(
 
 <!-- prettier-ignore -->
 ```ts source="./patterns.tsx#binaryBlobResourceClient"
-const result = await app.request(
-  { method: "resources/read", params: { uri: `video://${videoId}` } },
-  ReadResourceResultSchema,
-);
+const result = await app.readServerResource({ uri: `video://${videoId}` });
 
 const content = result.contents[0];
 if (!content || !("blob" in content)) {
diff --git a/docs/patterns.tsx b/docs/patterns.tsx
index 6b876926b..bb9eaa492 100644
--- a/docs/patterns.tsx
+++ b/docs/patterns.tsx
@@ -17,16 +17,12 @@ import { randomUUID } from "node:crypto";
 import type {
   CallToolResult,
   ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
-import { ReadResourceResultSchema } from "@modelcontextprotocol/sdk/types.js";
+} from "@modelcontextprotocol/server";
 import type { McpUiHostContext } from "../src/types.js";
 import { useEffect, useState } from "react";
 import { useApp } from "../src/react/index.js";
 import { registerAppTool } from "../src/server/index.js";
-import {
-  McpServer,
-  ResourceTemplate,
-} from "@modelcontextprotocol/sdk/server/mcp.js";
+import { McpServer, ResourceTemplate } from "@modelcontextprotocol/server";
 import { z } from "zod";
 
 /**
@@ -117,14 +113,14 @@ function chunkedDataServer(server: McpServer) {
     {
       title: "Read Data Bytes",
       description: "Load binary data in chunks",
-      inputSchema: {
+      inputSchema: z.object({
         id: z.string().describe("Resource identifier"),
         offset: z.number().min(0).default(0).describe("Byte offset"),
         byteCount: z
           .number()
           .default(MAX_CHUNK_BYTES)
           .describe("Bytes to read"),
-      },
+      }),
       outputSchema: DataChunkSchema,
       // Hidden from model - only callable by the App
       _meta: { ui: { visibility: ["app"] } },
@@ -252,10 +248,7 @@ function binaryBlobResourceServer(
  */
 async function binaryBlobResourceClient(app: App, videoId: string) {
   //#region binaryBlobResourceClient
-  const result = await app.request(
-    { method: "resources/read", params: { uri: `video://${videoId}` } },
-    ReadResourceResultSchema,
-  );
+  const result = await app.readServerResource({ uri: `video://${videoId}` });
 
   const content = result.contents[0];
   if (!content || !("blob" in content)) {
diff --git a/docs/quickstart.md b/docs/quickstart.md
index 3e00796c5..eb6b096cb 100644
--- a/docs/quickstart.md
+++ b/docs/quickstart.md
@@ -21,7 +21,7 @@ This tutorial assumes you've built an MCP server before and are comfortable with
 
 We'll use the [MCP TypeScript SDK](https://github.com/modelcontextprotocol/typescript-sdk) to build the server.
 
-You'll also need Node.js 18+.
+You'll also need Node.js 20+.
 
 ## 1. Set up the project
 
@@ -37,7 +37,7 @@ Install the dependencies you'll need:
 
 ```bash
 npm init -y
-npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/sdk express cors
+npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/client@2.0.0-beta.4 @modelcontextprotocol/core@2.0.0-beta.4 @modelcontextprotocol/server@2.0.0-beta.4 @modelcontextprotocol/node@2.0.0-beta.4 @modelcontextprotocol/express@2.0.0-beta.4 zod@^4.2.0 express cors
 npm install -D typescript vite vite-plugin-singlefile @types/express @types/cors @types/node tsx concurrently cross-env
 ```
 
@@ -178,9 +178,10 @@ import {
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { McpServer } from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { z } from "zod";
 
 const DIST_DIR = path.join(import.meta.dirname, "dist");
 
@@ -205,7 +206,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async () => {
@@ -240,10 +241,10 @@ export function createServer(): McpServer {
 
 <!-- prettier-ignore -->
 ```ts source="../examples/quickstart/main.ts"
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -263,7 +264,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/docs/testing-mcp-apps.md b/docs/testing-mcp-apps.md
index df1396c5f..e5d82b53e 100644
--- a/docs/testing-mcp-apps.md
+++ b/docs/testing-mcp-apps.md
@@ -28,6 +28,10 @@ The [`basic-host`](https://github.com/modelcontextprotocol/ext-apps/tree/main/ex
    cd examples/basic-host
    ```
 
+   The root install runs the package build, including type-checking the
+   documentation snippets against the exact base MCP SDK beta.4 packages. Do
+   not bypass a failed build before testing the host.
+
 2. Start basic-host, pointing it to your MCP server:
 
    ```bash
diff --git a/examples/basic-host/package.json b/examples/basic-host/package.json
index 1b45dcf18..583d2ffa9 100644
--- a/examples/basic-host/package.json
+++ b/examples/basic-host/package.json
@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",
     "zod": "^4.1.13"
diff --git a/examples/basic-host/src/implementation.ts b/examples/basic-host/src/implementation.ts
index 31e36983e..5f680ffdc 100644
--- a/examples/basic-host/src/implementation.ts
+++ b/examples/basic-host/src/implementation.ts
@@ -1,8 +1,12 @@
 import { RESOURCE_MIME_TYPE, getToolUiResourceUri, type McpUiSandboxProxyReadyNotification, AppBridge, PostMessageTransport, type McpUiResourceCsp, type McpUiResourcePermissions, buildAllowAttribute, type McpUiUpdateModelContextRequest, type McpUiMessageRequest } from "@modelcontextprotocol/ext-apps/app-bridge";
-import { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import { SSEClientTransport } from "@modelcontextprotocol/sdk/client/sse.js";
-import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js";
-import type { CallToolResult, Resource, Tool } from "@modelcontextprotocol/sdk/types.js";
+import {
+  Client,
+  SSEClientTransport,
+  StreamableHTTPClientTransport,
+  type CallToolResult,
+  type Resource,
+  type Tool,
+} from "@modelcontextprotocol/client";
 import { getTheme, onThemeChange } from "./theme";
 import { HOST_STYLE_VARIABLES } from "./host-styles";
 
diff --git a/examples/basic-host/src/index.tsx b/examples/basic-host/src/index.tsx
index 3d488a792..00c0d52b2 100644
--- a/examples/basic-host/src/index.tsx
+++ b/examples/basic-host/src/index.tsx
@@ -1,5 +1,5 @@
 import { getToolUiResourceUri, McpUiToolMetaSchema } from "@modelcontextprotocol/ext-apps/app-bridge";
-import type { Tool } from "@modelcontextprotocol/sdk/types.js";
+import type { Tool } from "@modelcontextprotocol/client";
 import { Component, type ErrorInfo, type ReactNode, StrictMode, Suspense, use, useEffect, useMemo, useRef, useState } from "react";
 import { createRoot } from "react-dom/client";
 import { callTool, connectToServer, hasAppHtml, initializeApp, loadSandboxProxy, log, newAppBridge, type ServerInfo, type ToolCallInfo, type ModelContext, type AppMessage } from "./implementation";
diff --git a/examples/basic-server-preact/main.ts b/examples/basic-server-preact/main.ts
index 76426326d..ffdff5266 100644
--- a/examples/basic-server-preact/main.ts
+++ b/examples/basic-server-preact/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/basic-server-preact/package.json b/examples/basic-server-preact/package.json
index 512720205..0187827f8 100644
--- a/examples/basic-server-preact/package.json
+++ b/examples/basic-server-preact/package.json
@@ -24,8 +24,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "preact": "^10.0.0",
diff --git a/examples/basic-server-preact/server.ts b/examples/basic-server-preact/server.ts
index bf14ea599..dfec94aa1 100644
--- a/examples/basic-server-preact/server.ts
+++ b/examples/basic-server-preact/server.ts
@@ -1,8 +1,12 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { CallToolResult, ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { registerAppTool, registerAppResource, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
+import { z } from "zod";
 // Works both from source (server.ts) and compiled (dist/server.js)
 const DIST_DIR = import.meta.filename.endsWith(".ts")
   ? path.join(import.meta.dirname, "dist")
@@ -28,7 +32,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time as an ISO 8601 string.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/basic-server-preact/src/mcp-app.tsx b/examples/basic-server-preact/src/mcp-app.tsx
index a8bdc68b8..351a8ec21 100644
--- a/examples/basic-server-preact/src/mcp-app.tsx
+++ b/examples/basic-server-preact/src/mcp-app.tsx
@@ -8,7 +8,7 @@ import {
   applyHostStyleVariables,
   type McpUiHostContext,
 } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import { useCallback, useEffect, useState } from "preact/hooks";
 import { render } from "preact";
 import styles from "./mcp-app.module.css";
diff --git a/examples/basic-server-react/main.ts b/examples/basic-server-react/main.ts
index ec187b68a..21c5e18af 100644
--- a/examples/basic-server-react/main.ts
+++ b/examples/basic-server-react/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/basic-server-react/package.json b/examples/basic-server-react/package.json
index e4d12333f..dae7665e9 100644
--- a/examples/basic-server-react/package.json
+++ b/examples/basic-server-react/package.json
@@ -34,8 +34,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "react": "^19.2.0",
diff --git a/examples/basic-server-react/server.ts b/examples/basic-server-react/server.ts
index 23f6dda5a..d77c908c4 100644
--- a/examples/basic-server-react/server.ts
+++ b/examples/basic-server-react/server.ts
@@ -1,8 +1,12 @@
 import { registerAppResource, registerAppTool, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { CallToolResult, ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { z } from "zod";
 
 // Works both from source (server.ts) and compiled (dist/server.js)
 const DIST_DIR = import.meta.filename.endsWith(".ts")
@@ -29,7 +33,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time as an ISO 8601 string.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/basic-server-react/src/mcp-app.tsx b/examples/basic-server-react/src/mcp-app.tsx
index 6bb554025..2b5fbef9a 100644
--- a/examples/basic-server-react/src/mcp-app.tsx
+++ b/examples/basic-server-react/src/mcp-app.tsx
@@ -3,7 +3,7 @@
  */
 import type { App, McpUiHostContext } from "@modelcontextprotocol/ext-apps";
 import { useApp } from "@modelcontextprotocol/ext-apps/react";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import { StrictMode, useCallback, useEffect, useState } from "react";
 import { createRoot } from "react-dom/client";
 import styles from "./mcp-app.module.css";
diff --git a/examples/basic-server-solid/main.ts b/examples/basic-server-solid/main.ts
index c8d9de225..095ef8dfd 100644
--- a/examples/basic-server-solid/main.ts
+++ b/examples/basic-server-solid/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/basic-server-solid/package.json b/examples/basic-server-solid/package.json
index 8f75ac8c2..5d9140761 100644
--- a/examples/basic-server-solid/package.json
+++ b/examples/basic-server-solid/package.json
@@ -24,8 +24,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "solid-js": "1.9.10",
diff --git a/examples/basic-server-solid/server.ts b/examples/basic-server-solid/server.ts
index 2ed2d9356..addb52260 100644
--- a/examples/basic-server-solid/server.ts
+++ b/examples/basic-server-solid/server.ts
@@ -1,8 +1,12 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { CallToolResult, ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { registerAppTool, registerAppResource, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
+import { z } from "zod";
 // Works both from source (server.ts) and compiled (dist/server.js)
 const DIST_DIR = import.meta.filename.endsWith(".ts")
   ? path.join(import.meta.dirname, "dist")
@@ -28,7 +32,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time as an ISO 8601 string.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/basic-server-solid/src/mcp-app.tsx b/examples/basic-server-solid/src/mcp-app.tsx
index 66d47f3f6..2d78b7b33 100644
--- a/examples/basic-server-solid/src/mcp-app.tsx
+++ b/examples/basic-server-solid/src/mcp-app.tsx
@@ -8,7 +8,7 @@ import {
   applyHostStyleVariables,
   type McpUiHostContext,
 } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import { createEffect, createSignal, onMount, Show } from "solid-js";
 import { render } from "solid-js/web";
 import styles from "./mcp-app.module.css";
diff --git a/examples/basic-server-svelte/main.ts b/examples/basic-server-svelte/main.ts
index 6c50a254f..734ec0cdb 100644
--- a/examples/basic-server-svelte/main.ts
+++ b/examples/basic-server-svelte/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/basic-server-svelte/package.json b/examples/basic-server-svelte/package.json
index f877bf7c8..18bf7abed 100644
--- a/examples/basic-server-svelte/package.json
+++ b/examples/basic-server-svelte/package.json
@@ -24,8 +24,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "svelte": "^5.0.0",
diff --git a/examples/basic-server-svelte/server.ts b/examples/basic-server-svelte/server.ts
index da603ca8d..941428514 100644
--- a/examples/basic-server-svelte/server.ts
+++ b/examples/basic-server-svelte/server.ts
@@ -1,8 +1,12 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { CallToolResult, ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { registerAppTool, registerAppResource, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
+import { z } from "zod";
 // Works both from source (server.ts) and compiled (dist/server.js)
 const DIST_DIR = import.meta.filename.endsWith(".ts")
   ? path.join(import.meta.dirname, "dist")
@@ -28,7 +32,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time as an ISO 8601 string.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/basic-server-svelte/src/App.svelte b/examples/basic-server-svelte/src/App.svelte
index fde128dde..cabcc317d 100644
--- a/examples/basic-server-svelte/src/App.svelte
+++ b/examples/basic-server-svelte/src/App.svelte
@@ -7,7 +7,7 @@ import {
   applyHostStyleVariables,
   type McpUiHostContext,
 } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 
 function extractTime(result: CallToolResult): string {
   const { text } = result.content?.find((c) => c.type === "text")!;
diff --git a/examples/basic-server-vanillajs/main.ts b/examples/basic-server-vanillajs/main.ts
index 286fa34f0..4de733187 100644
--- a/examples/basic-server-vanillajs/main.ts
+++ b/examples/basic-server-vanillajs/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/basic-server-vanillajs/package.json b/examples/basic-server-vanillajs/package.json
index 5d47f2cdc..6bb75af46 100644
--- a/examples/basic-server-vanillajs/package.json
+++ b/examples/basic-server-vanillajs/package.json
@@ -24,8 +24,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "zod": "^4.1.13"
diff --git a/examples/basic-server-vanillajs/server.ts b/examples/basic-server-vanillajs/server.ts
index 5b2daf704..693d86148 100644
--- a/examples/basic-server-vanillajs/server.ts
+++ b/examples/basic-server-vanillajs/server.ts
@@ -1,6 +1,9 @@
 import { registerAppResource, registerAppTool, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { CallToolResult, ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -29,7 +32,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time as an ISO 8601 string.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       outputSchema: z.object({
         time: z.string(),
       }),
diff --git a/examples/basic-server-vanillajs/src/mcp-app.ts b/examples/basic-server-vanillajs/src/mcp-app.ts
index c3168c214..6b5084a3a 100644
--- a/examples/basic-server-vanillajs/src/mcp-app.ts
+++ b/examples/basic-server-vanillajs/src/mcp-app.ts
@@ -8,7 +8,7 @@ import {
   applyHostStyleVariables,
   type McpUiHostContext,
 } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import "./global.css";
 import "./mcp-app.css";
 
diff --git a/examples/basic-server-vue/main.ts b/examples/basic-server-vue/main.ts
index 669a07189..d77426919 100644
--- a/examples/basic-server-vue/main.ts
+++ b/examples/basic-server-vue/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/basic-server-vue/package.json b/examples/basic-server-vue/package.json
index d27ddc91b..3b34aa686 100644
--- a/examples/basic-server-vue/package.json
+++ b/examples/basic-server-vue/package.json
@@ -24,8 +24,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "vue": "^3.5.0",
diff --git a/examples/basic-server-vue/server.ts b/examples/basic-server-vue/server.ts
index 5aa72de03..9adb9111e 100644
--- a/examples/basic-server-vue/server.ts
+++ b/examples/basic-server-vue/server.ts
@@ -1,8 +1,12 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { CallToolResult, ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { registerAppTool, registerAppResource, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
+import { z } from "zod";
 // Works both from source (server.ts) and compiled (dist/server.js)
 const DIST_DIR = import.meta.filename.endsWith(".ts")
   ? path.join(import.meta.dirname, "dist")
@@ -28,7 +32,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time as an ISO 8601 string.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/basic-server-vue/src/App.vue b/examples/basic-server-vue/src/App.vue
index 196ad64da..a45c26208 100644
--- a/examples/basic-server-vue/src/App.vue
+++ b/examples/basic-server-vue/src/App.vue
@@ -7,7 +7,7 @@ import {
   applyHostStyleVariables,
   type McpUiHostContext,
 } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 
 function extractTime(result: CallToolResult): string {
   const { text } = result.content?.find((c) => c.type === "text")!;
diff --git a/examples/budget-allocator-server/main.ts b/examples/budget-allocator-server/main.ts
index cc488f0b1..02c03cb59 100644
--- a/examples/budget-allocator-server/main.ts
+++ b/examples/budget-allocator-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/budget-allocator-server/package.json b/examples/budget-allocator-server/package.json
index 19a1d2554..5d4fe8ebb 100644
--- a/examples/budget-allocator-server/package.json
+++ b/examples/budget-allocator-server/package.json
@@ -27,7 +27,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "chart.js": "^4.4.0",
     "cors": "^2.8.5",
     "express": "^5.1.0",
diff --git a/examples/budget-allocator-server/server.ts b/examples/budget-allocator-server/server.ts
index 04fba11fe..01f5dbfb6 100755
--- a/examples/budget-allocator-server/server.ts
+++ b/examples/budget-allocator-server/server.ts
@@ -4,11 +4,11 @@
  * Provides budget configuration, 24 months of historical allocation data,
  * and industry benchmarks by company stage.
  */
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -270,7 +270,7 @@ export function createServer(): McpServer {
       title: "Get Budget Data",
       description:
         "Returns budget configuration with 24 months of historical allocations and industry benchmarks by company stage. The widget is interactive and exposes tools for reading/modifying allocations, adjusting budgets, and comparing against industry benchmarks.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       outputSchema: BudgetDataResponseSchema,
       _meta: { ui: { resourceUri } },
     },
diff --git a/examples/cohort-heatmap-server/main.ts b/examples/cohort-heatmap-server/main.ts
index d59903b34..8b33603ba 100644
--- a/examples/cohort-heatmap-server/main.ts
+++ b/examples/cohort-heatmap-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/cohort-heatmap-server/package.json b/examples/cohort-heatmap-server/package.json
index 8d1268b5c..c54040a53 100644
--- a/examples/cohort-heatmap-server/package.json
+++ b/examples/cohort-heatmap-server/package.json
@@ -27,7 +27,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "react": "^19.2.0",
diff --git a/examples/cohort-heatmap-server/server.ts b/examples/cohort-heatmap-server/server.ts
index 6d07144a2..129e2dc9e 100644
--- a/examples/cohort-heatmap-server/server.ts
+++ b/examples/cohort-heatmap-server/server.ts
@@ -1,5 +1,7 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -178,8 +180,8 @@ export function createServer(): McpServer {
       title: "Get Cohort Retention Data",
       description:
         "Returns cohort retention heatmap data showing customer retention over time by signup month",
-      inputSchema: GetCohortDataInputSchema.shape,
-      outputSchema: CohortDataSchema.shape,
+      inputSchema: GetCohortDataInputSchema,
+      outputSchema: CohortDataSchema,
       _meta: { ui: { resourceUri } },
     },
     async ({ metric, periodType, cohortCount, maxPeriods }) => {
diff --git a/examples/customer-segmentation-server/main.ts b/examples/customer-segmentation-server/main.ts
index 130076c58..c78875777 100644
--- a/examples/customer-segmentation-server/main.ts
+++ b/examples/customer-segmentation-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/customer-segmentation-server/package.json b/examples/customer-segmentation-server/package.json
index 4511de903..ef14b3264 100644
--- a/examples/customer-segmentation-server/package.json
+++ b/examples/customer-segmentation-server/package.json
@@ -27,7 +27,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "chart.js": "^4.4.0",
     "cors": "^2.8.5",
     "express": "^5.1.0",
diff --git a/examples/customer-segmentation-server/server.ts b/examples/customer-segmentation-server/server.ts
index 244415d1f..7cc1c1fe2 100644
--- a/examples/customer-segmentation-server/server.ts
+++ b/examples/customer-segmentation-server/server.ts
@@ -1,8 +1,8 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -100,8 +100,8 @@ export function createServer(): McpServer {
         title: "Get Customer Data",
         description:
           "Returns customer data with segment information for visualization. Optionally filter by segment.",
-        inputSchema: GetCustomerDataInputSchema.shape,
-        outputSchema: GetCustomerDataOutputSchema.shape,
+        inputSchema: GetCustomerDataInputSchema,
+        outputSchema: GetCustomerDataOutputSchema,
         _meta: { ui: { resourceUri } },
       },
       async ({ segment }): Promise<CallToolResult> => {
diff --git a/examples/debug-server/main.ts b/examples/debug-server/main.ts
index 3c89a975b..9fb0825f8 100644
--- a/examples/debug-server/main.ts
+++ b/examples/debug-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/debug-server/package.json b/examples/debug-server/package.json
index 3417a8fe9..0e3f508f7 100644
--- a/examples/debug-server/package.json
+++ b/examples/debug-server/package.json
@@ -35,7 +35,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "zod": "^4.1.13"
   },
   "devDependencies": {
diff --git a/examples/debug-server/server.ts b/examples/debug-server/server.ts
index fd3452a19..068f94da3 100644
--- a/examples/debug-server/server.ts
+++ b/examples/debug-server/server.ts
@@ -3,11 +3,11 @@ import {
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import { appendFileSync } from "node:fs";
 import path from "node:path";
diff --git a/examples/integration-server/main.ts b/examples/integration-server/main.ts
index c45787e2b..9a42842df 100644
--- a/examples/integration-server/main.ts
+++ b/examples/integration-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/integration-server/package.json b/examples/integration-server/package.json
index f6715a4ff..56fc8eda6 100644
--- a/examples/integration-server/package.json
+++ b/examples/integration-server/package.json
@@ -15,8 +15,11 @@
     "serve": "bun --watch main.ts"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "react": "^19.2.0",
diff --git a/examples/integration-server/server.ts b/examples/integration-server/server.ts
index e44689d24..346f4f7a8 100644
--- a/examples/integration-server/server.ts
+++ b/examples/integration-server/server.ts
@@ -3,11 +3,11 @@ import {
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -33,7 +33,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       outputSchema: z.object({
         time: z.string(),
       }),
@@ -72,7 +72,7 @@ export function createServer(): McpServer {
   );
 
   // Sample downloadable resource — used to demo ResourceLink in ui/download-file
-  server.resource(
+  server.registerResource(
     SAMPLE_DOWNLOAD_URI,
     SAMPLE_DOWNLOAD_URI,
     {
diff --git a/examples/integration-server/src/mcp-app.tsx b/examples/integration-server/src/mcp-app.tsx
index 7f0b18c27..281a35674 100644
--- a/examples/integration-server/src/mcp-app.tsx
+++ b/examples/integration-server/src/mcp-app.tsx
@@ -3,7 +3,7 @@
  */
 import type { App, McpUiHostContext } from "@modelcontextprotocol/ext-apps";
 import { useApp } from "@modelcontextprotocol/ext-apps/react";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import { StrictMode, useCallback, useEffect, useState } from "react";
 import { createRoot } from "react-dom/client";
 import styles from "./mcp-app.module.css";
diff --git a/examples/lazy-auth-server/package.json b/examples/lazy-auth-server/package.json
index f3ed6cd27..6aef3e12f 100644
--- a/examples/lazy-auth-server/package.json
+++ b/examples/lazy-auth-server/package.json
@@ -23,10 +23,12 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
-    "jose": "^6.0.0"
+    "jose": "^6.0.0",
+    "zod": "^4.1.13"
   },
   "devDependencies": {
     "@types/cors": "^2.8.19",
diff --git a/examples/lazy-auth-server/server.ts b/examples/lazy-auth-server/server.ts
index fe7b1acb5..01535ebfd 100644
--- a/examples/lazy-auth-server/server.ts
+++ b/examples/lazy-auth-server/server.ts
@@ -21,13 +21,13 @@ import {
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
-import { UrlElicitationRequiredError } from "@modelcontextprotocol/sdk/types.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import {
+  McpServer,
+  UrlElicitationRequiredError,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import cors from "cors";
 import express, { type Express, type Request, type Response } from "express";
 import { SignJWT, jwtVerify } from "jose";
@@ -35,6 +35,7 @@ import crypto from "node:crypto";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
+import { z } from "zod";
 
 // Works both from source (server.ts) and compiled (dist/server.js). Derived
 // from import.meta.url rather than import.meta.filename/dirname, which are
@@ -605,7 +606,7 @@ export function createServer(authInfo?: AuthInfo, req?: Request): McpServer {
       title: "Show Auth Button",
       description:
         "Public tool: shows a button that triggers the protected get_secret tool.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri: buttonUri } },
     },
     async (): Promise<CallToolResult> => ({
@@ -638,7 +639,7 @@ export function createServer(authInfo?: AuthInfo, req?: Request): McpServer {
       title: "Get Secret",
       description:
         "Protected tool: returns secret data. Requires authentication.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri: secretUri } },
     },
     async (): Promise<CallToolResult> => {
@@ -682,7 +683,7 @@ export function createServer(authInfo?: AuthInfo, req?: Request): McpServer {
       title: "Revoke Auth Token",
       description:
         "Protected tool: revokes the caller's entire auth session (access + refresh token).",
-      inputSchema: {},
+      inputSchema: z.object({}),
     },
     async (): Promise<CallToolResult> => {
       if (!authInfo) {
@@ -720,7 +721,7 @@ export function createServer(authInfo?: AuthInfo, req?: Request): McpServer {
       title: "Elicit URL (session-callback)",
       description:
         "URL elicitation via elicitInput. Blocks until the client accepts; sends ElicitCompleteNotification before returning.",
-      inputSchema: {},
+      inputSchema: z.object({}),
     },
     async (_args, extra): Promise<CallToolResult> => {
       const eid = crypto.randomUUID();
@@ -735,7 +736,7 @@ export function createServer(authInfo?: AuthInfo, req?: Request): McpServer {
           message: "Please open this URL to continue.",
           elicitationId: eid,
         },
-        { relatedRequestId: extra.requestId, timeout: 300_000 },
+        { relatedRequestId: extra.mcpReq.id, timeout: 300_000 },
       );
       // Send completion notification before returning — lands on the same SSE
       // stream as this tool response. For Streamable HTTP this is the ONLY
@@ -767,7 +768,7 @@ export function createServer(authInfo?: AuthInfo, req?: Request): McpServer {
       title: "Elicit by -32042 Error",
       description:
         "Throws UrlElicitationRequiredError (-32042). Client must open the URL, then retry. On retry, if the last-issued elicitationId was completed, sends ElicitCompleteNotification and succeeds.",
-      inputSchema: {},
+      inputSchema: z.object({}),
     },
     async (): Promise<CallToolResult> => {
       // Retry path: check if the user completed the elicitation we last issued.
@@ -1031,7 +1032,7 @@ export function createApp(): Express {
     }
 
     const server = createServer(authInfo, req);
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
     res.on("close", () => {
diff --git a/examples/map-server/main.ts b/examples/map-server/main.ts
index f91f57b6e..80383942d 100644
--- a/examples/map-server/main.ts
+++ b/examples/map-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/map-server/package.json b/examples/map-server/package.json
index 5dc23fe20..a3639ce5e 100644
--- a/examples/map-server/package.json
+++ b/examples/map-server/package.json
@@ -26,8 +26,11 @@
     "serve": "bun --watch main.ts"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "zod": "^4.1.13"
diff --git a/examples/map-server/server.ts b/examples/map-server/server.ts
index 10125a641..5767d46ba 100644
--- a/examples/map-server/server.ts
+++ b/examples/map-server/server.ts
@@ -5,11 +5,11 @@
  * - geocode: Search for places using OpenStreetMap Nominatim
  * - show-map: Display an interactive 3D globe at a given location
  */
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -148,7 +148,7 @@ export function createServer(): McpServer {
       title: "Show Map",
       description:
         "Display an interactive world map zoomed to a specific bounding box. Use the GeoCode tool to find the bounding box of a location. The widget is interactive and exposes tools for navigation (fly to locations) and querying the current view.",
-      inputSchema: {
+      inputSchema: z.object({
         west: z
           .number()
           .optional()
@@ -173,7 +173,7 @@ export function createServer(): McpServer {
           .string()
           .optional()
           .describe("Optional label to display on the map"),
-      },
+      }),
       _meta: { ui: { resourceUri } },
     },
     async ({ west, south, east, north, label }): Promise<CallToolResult> => ({
@@ -196,13 +196,13 @@ export function createServer(): McpServer {
       title: "Geocode",
       description:
         "Search for places using OpenStreetMap. Returns coordinates and bounding boxes for up to 5 matches.",
-      inputSchema: {
+      inputSchema: z.object({
         query: z
           .string()
           .describe(
             "Place name or address to search for (e.g., 'Paris', 'Golden Gate Bridge', '1600 Pennsylvania Ave')",
           ),
-      },
+      }),
     },
     async ({ query }): Promise<CallToolResult> => {
       try {
diff --git a/examples/map-server/src/mcp-app.ts b/examples/map-server/src/mcp-app.ts
index 39d7c2a22..d3090c7a4 100644
--- a/examples/map-server/src/mcp-app.ts
+++ b/examples/map-server/src/mcp-app.ts
@@ -6,7 +6,7 @@
  * a navigate-to tool for the host to control navigation.
  */
 import { App } from "@modelcontextprotocol/ext-apps";
-import type { ContentBlock } from "@modelcontextprotocol/sdk/spec.types.js";
+import type { ContentBlock } from "@modelcontextprotocol/client";
 import { z } from "zod";
 
 // TypeScript declaration for Cesium loaded from CDN
diff --git a/examples/pdf-server/main.ts b/examples/pdf-server/main.ts
index 1ff848a3e..bb7b57f42 100644
--- a/examples/pdf-server/main.ts
+++ b/examples/pdf-server/main.ts
@@ -6,10 +6,10 @@
 
 import fs from "node:fs";
 import path from "node:path";
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import {
@@ -39,7 +39,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/pdf-server/package.json b/examples/pdf-server/package.json
index 4d960f175..a7eb4bb95 100644
--- a/examples/pdf-server/package.json
+++ b/examples/pdf-server/package.json
@@ -26,8 +26,11 @@
   },
   "dependencies": {
     "@cantoo/pdf-lib": "^2.6.5",
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "pdfjs-dist": "^5.0.0",
diff --git a/examples/pdf-server/server.test.ts b/examples/pdf-server/server.test.ts
index 33a03f1fd..0b2a5eb4d 100644
--- a/examples/pdf-server/server.test.ts
+++ b/examples/pdf-server/server.test.ts
@@ -2,8 +2,7 @@ import { describe, it, expect, beforeEach, afterEach, spyOn } from "bun:test";
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
-import { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
+import { Client, InMemoryTransport } from "@modelcontextprotocol/client";
 import { getDocument } from "pdfjs-dist/legacy/build/pdf.mjs";
 import { PDFDocument } from "@cantoo/pdf-lib";
 import { makeRandomJpeg } from "../../tests/helpers/range-counting-server";
diff --git a/examples/pdf-server/server.ts b/examples/pdf-server/server.ts
index 93dedfdc9..e67cd4731 100644
--- a/examples/pdf-server/server.ts
+++ b/examples/pdf-server/server.ts
@@ -13,18 +13,19 @@
 import { randomUUID } from "crypto";
 import fs from "node:fs";
 import path from "node:path";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { Server } from "@modelcontextprotocol/sdk/server/index.js";
 import {
   registerAppResource,
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
 import {
-  RootsListChangedNotificationSchema,
+  McpServer,
   type CallToolResult,
+  type ElicitResult,
+  type PrimitiveSchemaDefinition,
   type ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+  type Server,
+} from "@modelcontextprotocol/server";
 // Stub DOMMatrix/ImageData/Path2D before pdfjs-dist loads — its legacy
 // build instantiates DOMMatrix at module scope and the @napi-rs/canvas
 // polyfill is unreliable under npx. See ./pdfjs-polyfill.ts for details.
@@ -62,10 +63,6 @@ class FetchStandardFontDataFactory {
     return new Uint8Array(await res.arrayBuffer());
   }
 }
-import type {
-  PrimitiveSchemaDefinition,
-  ElicitResult,
-} from "@modelcontextprotocol/sdk/types.js";
 import { z } from "zod";
 
 // =============================================================================
@@ -1282,7 +1279,7 @@ export function createServer(options: CreateServerOptions = {}): McpServer {
       refreshRoots(server.server);
     };
     server.server.setNotificationHandler(
-      RootsListChangedNotificationSchema,
+      "notifications/roots/list_changed",
       async () => {
         await refreshRoots(server.server);
       },
@@ -1292,10 +1289,12 @@ export function createServer(options: CreateServerOptions = {}): McpServer {
   const { readPdfRange } = sharedPdfCache;
 
   // Tool: list_pdfs - List available PDFs
-  server.tool(
+  server.registerTool(
     "list_pdfs",
-    "List available PDFs that can be displayed",
-    {},
+    {
+      description: "List available PDFs that can be displayed",
+      inputSchema: z.object({}),
+    },
     async (): Promise<CallToolResult> => {
       const seen = new Set<string>();
       const localFiles: string[] = [];
@@ -1377,7 +1376,7 @@ export function createServer(options: CreateServerOptions = {}): McpServer {
       title: "Read PDF Bytes",
       description:
         "Read a range of bytes from a PDF (max 512KB per request). The model should NOT call this tool directly.",
-      inputSchema: {
+      inputSchema: z.object({
         url: z.string().describe("PDF URL or local file path"),
         offset: z.number().min(0).default(0).describe("Byte offset"),
         byteCount: z
@@ -1386,7 +1385,7 @@ export function createServer(options: CreateServerOptions = {}): McpServer {
           .max(MAX_CHUNK_BYTES)
           .default(MAX_CHUNK_BYTES)
           .describe("Bytes to read"),
-      },
+      }),
       outputSchema: z.object({
         url: z.string(),
         bytes: z.string().describe("Base64 encoded bytes"),
@@ -1473,7 +1472,7 @@ Returns a viewUUID in structuredContent. Pass it to \`interact\`:
 
 Accepts local files (use list_pdfs), client MCP root directories, or any HTTPS URL.
 Set \`elicit_form_inputs\` to true to prompt the user to fill form fields before display.`,
-      inputSchema: {
+      inputSchema: z.object({
         url: z
           .string()
           .default(DEFAULT_PDF)
@@ -1489,7 +1488,7 @@ Set \`elicit_form_inputs\` to true to prompt the user to fill form fields before
                   "If true and the PDF has form fields, prompt the user to fill them before displaying",
                 ),
             }),
-      },
+      }),
       outputSchema: z.object({
         viewUUID: z
           .string()
@@ -2426,7 +2425,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
 **FORMS** — fill_form: fill fields with \`fields\` array of {name, value}.
 
 **SAVE** — save_as: write the annotated PDF (annotations + form values) to a file. Pass \`path\` (absolute path or file://) for a new location, or omit \`path\` to overwrite the original. Set \`overwrite: true\` to replace an existing file (always required when omitting \`path\`).`,
-        inputSchema: {
+        inputSchema: z.object({
           viewUUID: z
             .string()
             .describe(
@@ -2523,7 +2522,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
             .describe(
               "Array of commands to execute sequentially. More efficient than separate calls. Tip: end with get_pages+getScreenshots to verify changes.",
             ),
-        },
+        }),
       },
       async (
         {
@@ -2600,7 +2599,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
           const result = await processInteractCommand(
             uuid,
             commandList[i],
-            extra.signal,
+            extra.mcpReq.signal,
           );
           if (result.isError) {
             const errText = result.content
@@ -2657,7 +2656,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
         title: "Submit Page Data",
         description:
           "Submit rendered page data for a get_pages request (used by viewer). The model should NOT call this tool directly.",
-        inputSchema: {
+        inputSchema: z.object({
           requestId: z
             .string()
             .describe("The request ID from the get_pages command"),
@@ -2670,7 +2669,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
               }),
             )
             .describe("Page data entries"),
-        },
+        }),
         _meta: { ui: { visibility: ["app"] } },
       },
       async ({ requestId, pages }): Promise<CallToolResult> => {
@@ -2700,7 +2699,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
         title: "Submit Save Data",
         description:
           "Submit annotated PDF bytes for a save_as request (used by viewer). The model should NOT call this tool directly.",
-        inputSchema: {
+        inputSchema: z.object({
           requestId: z
             .string()
             .describe("The request ID from the save_as command"),
@@ -2709,7 +2708,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
             .string()
             .optional()
             .describe("Error message if the viewer failed to build bytes"),
-        },
+        }),
         _meta: { ui: { visibility: ["app"] } },
       },
       async ({ requestId, data, error }): Promise<CallToolResult> => {
@@ -2739,7 +2738,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
         title: "Submit Viewer State",
         description:
           "Submit a viewer-state snapshot for a get_viewer_state request (used by viewer). The model should NOT call this tool directly.",
-        inputSchema: {
+        inputSchema: z.object({
           requestId: z
             .string()
             .describe("The request ID from the get_viewer_state command"),
@@ -2751,7 +2750,7 @@ Example — add a signature image and a stamp, then screenshot to verify:
             .string()
             .optional()
             .describe("Error message if the viewer failed to read state"),
-        },
+        }),
         _meta: { ui: { visibility: ["app"] } },
       },
       async ({ requestId, state, error }): Promise<CallToolResult> => {
@@ -2781,9 +2780,9 @@ Example — add a signature image and a stamp, then screenshot to verify:
         title: "Poll PDF Commands",
         description:
           "Poll for pending commands for a PDF viewer. The model should NOT call this tool directly.",
-        inputSchema: {
+        inputSchema: z.object({
           viewUUID: z.string().describe("The viewUUID of the PDF viewer"),
-        },
+        }),
         _meta: { ui: { visibility: ["app"] } },
       },
       async ({ viewUUID: uuid }): Promise<CallToolResult> => {
@@ -2828,10 +2827,10 @@ Example — add a signature image and a stamp, then screenshot to verify:
       title: "Save PDF",
       description:
         "Save annotated PDF bytes back to a local file. The model should NOT call this tool directly — use interact with action: save_as instead.",
-      inputSchema: {
+      inputSchema: z.object({
         url: z.string().describe("Original PDF URL or local file path"),
         data: z.string().describe("Base64-encoded PDF bytes"),
-      },
+      }),
       outputSchema: z.object({
         filePath: z.string(),
         mtimeMs: z.number(),
diff --git a/examples/pdf-server/src/mcp-app.ts b/examples/pdf-server/src/mcp-app.ts
index a953e242a..45e0c7458 100644
--- a/examples/pdf-server/src/mcp-app.ts
+++ b/examples/pdf-server/src/mcp-app.ts
@@ -12,8 +12,10 @@ import {
   applyDocumentTheme,
   applyHostStyleVariables,
 } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
-import type { ContentBlock } from "@modelcontextprotocol/sdk/spec.types.js";
+import type {
+  CallToolResult,
+  ContentBlock,
+} from "@modelcontextprotocol/client";
 import { z } from "zod";
 import * as pdfjsLib from "pdfjs-dist";
 import { AnnotationLayer, AnnotationMode, TextLayer } from "pdfjs-dist";
diff --git a/examples/qr-server/package.json b/examples/qr-server/package.json
index a5cbf5b22..cb4e010ab 100644
--- a/examples/qr-server/package.json
+++ b/examples/qr-server/package.json
@@ -8,7 +8,6 @@
     "build": "echo 'No build step needed for Python server'"
   },
   "dependencies": {
-    "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0"
+    "@modelcontextprotocol/ext-apps": "^1.7.0"
   }
 }
diff --git a/examples/quickstart/main.ts b/examples/quickstart/main.ts
index 06895a49a..7f370a868 100644
--- a/examples/quickstart/main.ts
+++ b/examples/quickstart/main.ts
@@ -1,7 +1,7 @@
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -21,7 +21,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/quickstart/package.json b/examples/quickstart/package.json
index 99948cc2d..f741c6e29 100644
--- a/examples/quickstart/package.json
+++ b/examples/quickstart/package.json
@@ -16,9 +16,12 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
-    "express": "^5.1.0"
+    "express": "^5.1.0",
+    "zod": "^4.1.13"
   },
   "devDependencies": {
     "@types/cors": "^2.8.19",
diff --git a/examples/quickstart/server.ts b/examples/quickstart/server.ts
index eb3c3b1ab..611d0f072 100644
--- a/examples/quickstart/server.ts
+++ b/examples/quickstart/server.ts
@@ -3,9 +3,10 @@ import {
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { McpServer } from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { z } from "zod";
 
 const DIST_DIR = path.join(import.meta.dirname, "dist");
 
@@ -30,7 +31,7 @@ export function createServer(): McpServer {
     {
       title: "Get Time",
       description: "Returns the current server time.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } }, // Links this tool to its UI resource
     },
     async () => {
diff --git a/examples/say-server/package.json b/examples/say-server/package.json
index a0076e6b9..2ebc099e6 100644
--- a/examples/say-server/package.json
+++ b/examples/say-server/package.json
@@ -15,7 +15,6 @@
     "build": "echo 'No build step needed for Python server'"
   },
   "dependencies": {
-    "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0"
+    "@modelcontextprotocol/ext-apps": "^1.7.0"
   }
 }
diff --git a/examples/scenario-modeler-server/main.ts b/examples/scenario-modeler-server/main.ts
index dbd3ab6ae..cc20e639a 100644
--- a/examples/scenario-modeler-server/main.ts
+++ b/examples/scenario-modeler-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/scenario-modeler-server/package.json b/examples/scenario-modeler-server/package.json
index aa1e668ef..63a5d4871 100644
--- a/examples/scenario-modeler-server/package.json
+++ b/examples/scenario-modeler-server/package.json
@@ -27,7 +27,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "chart.js": "^4.4.0",
     "cors": "^2.8.5",
     "express": "^5.1.0",
diff --git a/examples/scenario-modeler-server/server.ts b/examples/scenario-modeler-server/server.ts
index b59851c40..c5fa05d35 100644
--- a/examples/scenario-modeler-server/server.ts
+++ b/examples/scenario-modeler-server/server.ts
@@ -3,11 +3,11 @@ import {
   registerAppResource,
   registerAppTool,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -305,8 +305,8 @@ export function createServer(): McpServer {
         title: "Get Scenario Data",
         description:
           "Returns SaaS scenario templates and optionally computes custom projections for given inputs",
-        inputSchema: GetScenarioDataInputSchema.shape,
-        outputSchema: GetScenarioDataOutputSchema.shape,
+        inputSchema: GetScenarioDataInputSchema,
+        outputSchema: GetScenarioDataOutputSchema,
         _meta: { ui: { resourceUri } },
       },
       async (args: {
diff --git a/examples/shadertoy-server/main.ts b/examples/shadertoy-server/main.ts
index ac8f6ad8e..7e388f0a6 100644
--- a/examples/shadertoy-server/main.ts
+++ b/examples/shadertoy-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/shadertoy-server/package.json b/examples/shadertoy-server/package.json
index ccf15a45c..318f01760 100644
--- a/examples/shadertoy-server/package.json
+++ b/examples/shadertoy-server/package.json
@@ -25,7 +25,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "zod": "^4.1.13"
diff --git a/examples/shadertoy-server/server.ts b/examples/shadertoy-server/server.ts
index 5238c40b7..50c27bc66 100644
--- a/examples/shadertoy-server/server.ts
+++ b/examples/shadertoy-server/server.ts
@@ -3,11 +3,11 @@ import {
   registerAppTool,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
diff --git a/examples/sheet-music-server/main.ts b/examples/sheet-music-server/main.ts
index 8b143a7ae..d7bf3a0b6 100644
--- a/examples/sheet-music-server/main.ts
+++ b/examples/sheet-music-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/sheet-music-server/package.json b/examples/sheet-music-server/package.json
index ca9fa909f..10d7c71bc 100644
--- a/examples/sheet-music-server/package.json
+++ b/examples/sheet-music-server/package.json
@@ -25,7 +25,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "abcjs": "^6.4.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
diff --git a/examples/sheet-music-server/server.ts b/examples/sheet-music-server/server.ts
index cfd319b51..be7214ae0 100644
--- a/examples/sheet-music-server/server.ts
+++ b/examples/sheet-music-server/server.ts
@@ -1,8 +1,8 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
diff --git a/examples/system-monitor-server/main.ts b/examples/system-monitor-server/main.ts
index 365a56046..c55c79973 100644
--- a/examples/system-monitor-server/main.ts
+++ b/examples/system-monitor-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/system-monitor-server/package.json b/examples/system-monitor-server/package.json
index 12e8cea06..5bc4a9585 100644
--- a/examples/system-monitor-server/package.json
+++ b/examples/system-monitor-server/package.json
@@ -27,7 +27,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "chart.js": "^4.4.0",
     "cors": "^2.8.5",
     "express": "^5.1.0",
diff --git a/examples/system-monitor-server/server.ts b/examples/system-monitor-server/server.ts
index 8fac5f2f9..a17bcf6c9 100644
--- a/examples/system-monitor-server/server.ts
+++ b/examples/system-monitor-server/server.ts
@@ -3,11 +3,11 @@ import {
   registerAppResource,
   registerAppTool,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
@@ -135,8 +135,8 @@ export function createServer(): McpServer {
       title: "Get System Info",
       description:
         "Returns system information, including hostname, platform, CPU info, and memory.",
-      inputSchema: {},
-      outputSchema: SystemInfoSchema.shape,
+      inputSchema: z.object({}),
+      outputSchema: SystemInfoSchema,
       _meta: { ui: { resourceUri } },
     },
     (): CallToolResult => {
@@ -156,8 +156,8 @@ export function createServer(): McpServer {
       title: "Poll System Stats",
       description:
         "Returns dynamic system metrics for polling: per-core CPU timing, memory usage, and uptime. App-only.",
-      inputSchema: {},
-      outputSchema: PollStatsSchema.shape,
+      inputSchema: z.object({}),
+      outputSchema: PollStatsSchema,
       _meta: { ui: { visibility: ["app"] } },
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/threejs-server/main.ts b/examples/threejs-server/main.ts
index 13a2084a8..ef16e26e2 100644
--- a/examples/threejs-server/main.ts
+++ b/examples/threejs-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/threejs-server/package.json b/examples/threejs-server/package.json
index cfb5686a6..fb97d333b 100644
--- a/examples/threejs-server/package.json
+++ b/examples/threejs-server/package.json
@@ -26,8 +26,11 @@
     "serve": "bun --watch main.ts"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "react": "^19.2.0",
diff --git a/examples/threejs-server/server.ts b/examples/threejs-server/server.ts
index ae320df80..0a13c19ef 100644
--- a/examples/threejs-server/server.ts
+++ b/examples/threejs-server/server.ts
@@ -8,8 +8,10 @@ import {
   registerAppResource,
   registerAppTool,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type { ReadResourceResult } from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -161,7 +163,7 @@ export function createServer(): McpServer {
       title: "Show Three.js Scene",
       description:
         "Render an interactive 3D scene with custom Three.js code. Supports transparent backgrounds (alpha: true) for seamless host UI integration. Available globals: THREE, OrbitControls, EffectComposer, RenderPass, UnrealBloomPass, canvas, width, height.",
-      inputSchema: {
+      inputSchema: z.object({
         code: z
           .string()
           .default(DEFAULT_THREEJS_CODE)
@@ -172,7 +174,7 @@ export function createServer(): McpServer {
           .positive()
           .default(400)
           .describe("Height in pixels"),
-      },
+      }),
       outputSchema: z.object({
         success: z.boolean(),
       }),
@@ -192,7 +194,7 @@ export function createServer(): McpServer {
     {
       title: "Learn Three.js",
       description: "Get documentation and examples for using the Three.js View",
-      inputSchema: {},
+      inputSchema: z.object({}),
     },
     async () => {
       return {
diff --git a/examples/threejs-server/src/mcp-app-wrapper.tsx b/examples/threejs-server/src/mcp-app-wrapper.tsx
index 34194b15f..44fee0c67 100644
--- a/examples/threejs-server/src/mcp-app-wrapper.tsx
+++ b/examples/threejs-server/src/mcp-app-wrapper.tsx
@@ -6,7 +6,7 @@
  */
 import type { App, McpUiHostContext } from "@modelcontextprotocol/ext-apps";
 import { useApp } from "@modelcontextprotocol/ext-apps/react";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import { StrictMode, useState, useCallback, useEffect, useRef } from "react";
 import { createRoot } from "react-dom/client";
 import { z } from "zod";
diff --git a/examples/transcript-server/main.ts b/examples/transcript-server/main.ts
index 68db8dc7d..e86ad7c16 100644
--- a/examples/transcript-server/main.ts
+++ b/examples/transcript-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -25,7 +25,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/transcript-server/package.json b/examples/transcript-server/package.json
index dcba3d7c0..eea4a80b5 100644
--- a/examples/transcript-server/package.json
+++ b/examples/transcript-server/package.json
@@ -25,7 +25,9 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "zod": "^4.1.13"
diff --git a/examples/transcript-server/server.ts b/examples/transcript-server/server.ts
index 56bf88d99..863eb2922 100644
--- a/examples/transcript-server/server.ts
+++ b/examples/transcript-server/server.ts
@@ -1,8 +1,8 @@
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import {
@@ -10,6 +10,7 @@ import {
   registerAppResource,
   RESOURCE_MIME_TYPE,
 } from "@modelcontextprotocol/ext-apps/server";
+import { z } from "zod";
 // Works both from source (server.ts) and compiled (dist/server.js)
 const DIST_DIR = import.meta.filename.endsWith(".ts")
   ? path.join(import.meta.dirname, "dist")
@@ -33,7 +34,7 @@ export function createServer(): McpServer {
       title: "Transcribe Speech",
       description:
         "Opens a live speech transcription interface using the Web Speech API.",
-      inputSchema: {},
+      inputSchema: z.object({}),
       _meta: { ui: { resourceUri } },
     },
     async (): Promise<CallToolResult> => {
diff --git a/examples/video-resource-server/main.ts b/examples/video-resource-server/main.ts
index 082fa5abc..1983373c6 100644
--- a/examples/video-resource-server/main.ts
+++ b/examples/video-resource-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/video-resource-server/package.json b/examples/video-resource-server/package.json
index b0d04aff1..ea816b93c 100644
--- a/examples/video-resource-server/package.json
+++ b/examples/video-resource-server/package.json
@@ -24,8 +24,11 @@
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cors": "^2.8.5",
     "express": "^5.1.0",
     "zod": "^4.1.13"
diff --git a/examples/video-resource-server/server.ts b/examples/video-resource-server/server.ts
index 2cb317e41..8ae624029 100644
--- a/examples/video-resource-server/server.ts
+++ b/examples/video-resource-server/server.ts
@@ -12,11 +12,9 @@ import {
 import {
   McpServer,
   ResourceTemplate,
-} from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { z } from "zod";
@@ -135,14 +133,14 @@ Available videos:
 ${Object.entries(VIDEO_LIBRARY)
   .map(([id, v]) => `- ${id}: ${v.description}`)
   .join("\n")}`,
-      inputSchema: {
+      inputSchema: z.object({
         videoId: z
           .enum(Object.keys(VIDEO_LIBRARY) as [string, ...string[]])
           .default("bunny-1mb")
           .describe(
             `Video ID to play. Available: ${Object.keys(VIDEO_LIBRARY).join(", ")}`,
           ),
-      },
+      }),
       outputSchema: z.object({
         videoUri: z.string(),
         description: z.string(),
diff --git a/examples/video-resource-server/src/mcp-app.ts b/examples/video-resource-server/src/mcp-app.ts
index 88ed913ee..2a3f8f91d 100644
--- a/examples/video-resource-server/src/mcp-app.ts
+++ b/examples/video-resource-server/src/mcp-app.ts
@@ -5,7 +5,7 @@
  * The video is served as a base64 blob and converted to a data URI for playback.
  */
 import { App, type McpUiHostContext } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import "./global.css";
 import "./mcp-app.css";
 
diff --git a/examples/wiki-explorer-server/main.ts b/examples/wiki-explorer-server/main.ts
index cc7b3a221..bfeeffbaa 100644
--- a/examples/wiki-explorer-server/main.ts
+++ b/examples/wiki-explorer-server/main.ts
@@ -4,10 +4,10 @@
  * Or: node dist/index.js [--stdio]
  */
 
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
-import { createMcpExpressApp } from "@modelcontextprotocol/sdk/server/express.js";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
+import { createMcpExpressApp } from "@modelcontextprotocol/express";
+import type { McpServer } from "@modelcontextprotocol/server";
+import { NodeStreamableHTTPServerTransport } from "@modelcontextprotocol/node";
 import cors from "cors";
 import type { Request, Response } from "express";
 import { createServer } from "./server.js";
@@ -27,7 +27,7 @@ export async function startStreamableHTTPServer(
 
   app.all("/mcp", async (req: Request, res: Response) => {
     const server = createServer();
-    const transport = new StreamableHTTPServerTransport({
+    const transport = new NodeStreamableHTTPServerTransport({
       sessionIdGenerator: undefined,
     });
 
diff --git a/examples/wiki-explorer-server/package.json b/examples/wiki-explorer-server/package.json
index fe511ad0f..bd31d6f78 100644
--- a/examples/wiki-explorer-server/package.json
+++ b/examples/wiki-explorer-server/package.json
@@ -26,8 +26,11 @@
     "serve": "bun --watch main.ts"
   },
   "dependencies": {
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
     "@modelcontextprotocol/ext-apps": "^1.7.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/express": "2.0.0-beta.4",
+    "@modelcontextprotocol/node": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "cheerio": "^1.0.0",
     "cors": "^2.8.5",
     "express": "^5.1.0",
diff --git a/examples/wiki-explorer-server/server.ts b/examples/wiki-explorer-server/server.ts
index 59d5e18ee..8bc4eb7cb 100644
--- a/examples/wiki-explorer-server/server.ts
+++ b/examples/wiki-explorer-server/server.ts
@@ -3,11 +3,11 @@ import {
   registerAppResource,
   registerAppTool,
 } from "@modelcontextprotocol/ext-apps/server";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  CallToolResult,
-  ReadResourceResult,
-} from "@modelcontextprotocol/sdk/types.js";
+import {
+  McpServer,
+  type CallToolResult,
+  type ReadResourceResult,
+} from "@modelcontextprotocol/server";
 import * as cheerio from "cheerio";
 import fs from "node:fs/promises";
 import path from "node:path";
diff --git a/examples/wiki-explorer-server/src/mcp-app.ts b/examples/wiki-explorer-server/src/mcp-app.ts
index 291292dee..9833d9c25 100644
--- a/examples/wiki-explorer-server/src/mcp-app.ts
+++ b/examples/wiki-explorer-server/src/mcp-app.ts
@@ -2,7 +2,7 @@
  * Wiki Explorer - Force-directed graph visualization of Wikipedia link networks
  */
 import { App, type McpUiHostContext } from "@modelcontextprotocol/ext-apps";
-import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolResult } from "@modelcontextprotocol/client";
 import { z } from "zod";
 import {
   forceCenter,
diff --git a/package-lock.json b/package-lock.json
index 29e905875..9e0a71b5f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -16,7 +16,9 @@
       },
       "devDependencies": {
         "@boneskull/typedoc-plugin-mermaid": "^0.2.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/core": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "@playwright/test": "1.57.0",
         "@types/bun": "^1.3.2",
         "@types/node": "20.19.27",
@@ -44,16 +46,18 @@
         "typedoc": "^0.28.14",
         "typedoc-github-theme": "^0.4.0",
         "typescript": "^5.9.3",
-        "zod": "^4.1.13"
+        "zod": "^4.2.0"
       },
       "engines": {
         "node": ">=20"
       },
       "peerDependencies": {
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/core": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "react": "^17.0.0 || ^18.0.0 || ^19.0.0",
         "react-dom": "^17.0.0 || ^18.0.0 || ^19.0.0",
-        "zod": "^3.25.0 || ^4.0.0"
+        "zod": "^4.2.0"
       },
       "peerDependenciesMeta": {
         "react": {
@@ -68,8 +72,8 @@
       "name": "@modelcontextprotocol/ext-apps-basic-host",
       "version": "1.7.4",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
         "react": "^19.2.0",
         "react-dom": "^19.2.0",
         "zod": "^4.1.13"
@@ -111,8 +115,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "preact": "^10.0.0",
@@ -155,8 +162,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "react": "^19.2.0",
@@ -202,8 +212,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "solid-js": "1.9.10",
@@ -246,8 +259,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "svelte": "^5.0.0",
@@ -290,8 +306,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "zod": "^4.1.13"
@@ -332,8 +351,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "vue": "^3.5.0",
@@ -376,8 +398,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "chart.js": "^4.4.0",
         "cors": "^2.8.5",
         "express": "^5.1.0",
@@ -419,8 +443,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "react": "^19.2.0",
@@ -466,8 +492,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "chart.js": "^4.4.0",
         "cors": "^2.8.5",
         "express": "^5.1.0",
@@ -509,8 +537,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "zod": "^4.1.13"
       },
       "bin": {
@@ -549,8 +579,11 @@
     "examples/integration-server": {
       "version": "1.7.4",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "react": "^19.2.0",
@@ -596,10 +629,12 @@
       "license": "MIT",
       "dependencies": {
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
-        "jose": "^6.0.0"
+        "jose": "^6.0.0",
+        "zod": "^4.1.13"
       },
       "bin": {
         "mcp-server-lazy-auth": "dist/index.js"
@@ -637,8 +672,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "zod": "^4.1.13"
@@ -680,8 +718,11 @@
       "license": "MIT",
       "dependencies": {
         "@cantoo/pdf-lib": "^2.6.5",
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "pdfjs-dist": "^5.0.0",
@@ -722,8 +763,7 @@
       "name": "@modelcontextprotocol/server-qr",
       "version": "1.7.4",
       "dependencies": {
-        "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0"
+        "@modelcontextprotocol/ext-apps": "^1.7.0"
       }
     },
     "examples/quickstart": {
@@ -731,10 +771,13 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
-        "express": "^5.1.0"
+        "express": "^5.1.0",
+        "zod": "^4.1.13"
       },
       "devDependencies": {
         "@types/cors": "^2.8.19",
@@ -763,8 +806,7 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
-        "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0"
+        "@modelcontextprotocol/ext-apps": "^1.7.0"
       }
     },
     "examples/scenario-modeler-server": {
@@ -772,8 +814,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "chart.js": "^4.4.0",
         "cors": "^2.8.5",
         "express": "^5.1.0",
@@ -820,8 +864,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "zod": "^4.1.13"
@@ -862,8 +908,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "abcjs": "^6.4.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
@@ -905,8 +953,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "chart.js": "^4.4.0",
         "cors": "^2.8.5",
         "express": "^5.1.0",
@@ -949,8 +999,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "react": "^19.2.0",
@@ -998,8 +1051,10 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "zod": "^4.1.13"
@@ -1041,8 +1096,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cors": "^2.8.5",
         "express": "^5.1.0",
         "zod": "^4.1.13"
@@ -1083,8 +1141,11 @@
       "version": "1.7.4",
       "license": "MIT",
       "dependencies": {
+        "@modelcontextprotocol/client": "2.0.0-beta.4",
+        "@modelcontextprotocol/express": "2.0.0-beta.4",
         "@modelcontextprotocol/ext-apps": "^1.7.0",
-        "@modelcontextprotocol/sdk": "^1.29.0",
+        "@modelcontextprotocol/node": "2.0.0-beta.4",
+        "@modelcontextprotocol/server": "2.0.0-beta.4",
         "cheerio": "^1.0.0",
         "cors": "^2.8.5",
         "express": "^5.1.0",
@@ -2576,6 +2637,52 @@
       "integrity": "sha512-M5UknZPHRu3DEDWoipU6sE8PdkZ6Z/S+v4dD+Ke8IaNlpdSQah50lz1KtcFBa2vsdOnwbbnxJwVM4wty6udA5w==",
       "license": "MIT"
     },
+    "node_modules/@modelcontextprotocol/client": {
+      "version": "2.0.0-beta.4",
+      "resolved": "https://registry.npmjs.org/@modelcontextprotocol/client/-/client-2.0.0-beta.4.tgz",
+      "integrity": "sha512-VNHA/UXDk7mCpVl+jOg5B4WMRRD2OEl+it360Lhi6HiCbrIB2f6pZ0cqSDKXQVUtZvqnhdQHzZAM9h8EKWhq/A==",
+      "license": "MIT",
+      "dependencies": {
+        "@modelcontextprotocol/core": "2.0.0-beta.4",
+        "cross-spawn": "^7.0.5",
+        "eventsource": "^3.0.2",
+        "eventsource-parser": "^3.0.0",
+        "jose": "^6.1.3",
+        "pkce-challenge": "^5.0.0",
+        "zod": "^4.2.0"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
+    "node_modules/@modelcontextprotocol/core": {
+      "version": "2.0.0-beta.4",
+      "resolved": "https://registry.npmjs.org/@modelcontextprotocol/core/-/core-2.0.0-beta.4.tgz",
+      "integrity": "sha512-nsMXd4wQBKzmph6r+WOhum+mXjDYljTAqwY/XUg3hLtvNOQ8+JVqBSJOVCMJvx9lXhTpTOPrGZ3BuNiaNPjSvg==",
+      "license": "MIT",
+      "dependencies": {
+        "zod": "^4.2.0"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
+    "node_modules/@modelcontextprotocol/express": {
+      "version": "2.0.0-beta.4",
+      "resolved": "https://registry.npmjs.org/@modelcontextprotocol/express/-/express-2.0.0-beta.4.tgz",
+      "integrity": "sha512-7hI8bEomz6rMn8sKYRVIZgQJsrWIjIS9WiPyIp3X2pMyLSCC7hB5km0kg+9SygWygTIRnPfte0tXevRB3mXEHQ==",
+      "license": "MIT",
+      "dependencies": {
+        "cors": "^2.8.5"
+      },
+      "engines": {
+        "node": ">=20"
+      },
+      "peerDependencies": {
+        "@modelcontextprotocol/server": "^2.0.0-beta.4",
+        "express": "^4.18.0 || ^5.0.0"
+      }
+    },
     "node_modules/@modelcontextprotocol/ext-apps": {
       "version": "1.7.1",
       "resolved": "https://registry.npmjs.org/@modelcontextprotocol/ext-apps/-/ext-apps-1.7.1.tgz",
@@ -2609,6 +2716,27 @@
       "resolved": "examples/basic-host",
       "link": true
     },
+    "node_modules/@modelcontextprotocol/node": {
+      "version": "2.0.0-beta.4",
+      "resolved": "https://registry.npmjs.org/@modelcontextprotocol/node/-/node-2.0.0-beta.4.tgz",
+      "integrity": "sha512-OqbrRVNYNfLxBB2BRkP5oIHKHa0IPHluMbaLgw7YCRKcj5be9ExzyWFJY3KVMb+1F2AVn+0SRoH0XKcNzh3HYQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@hono/node-server": "^1.19.9"
+      },
+      "engines": {
+        "node": ">=20"
+      },
+      "peerDependencies": {
+        "@modelcontextprotocol/server": "^2.0.0-beta.4",
+        "hono": "^4.11.4"
+      },
+      "peerDependenciesMeta": {
+        "hono": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/@modelcontextprotocol/quickstart": {
       "resolved": "examples/quickstart",
       "link": true
@@ -2618,6 +2746,7 @@
       "resolved": "https://registry.npmjs.org/@modelcontextprotocol/sdk/-/sdk-1.29.0.tgz",
       "integrity": "sha512-zo37mZA9hJWpULgkRpowewez1y6ML5GsXJPY8FI0tBBCd77HEvza4jDqRKOXgHNn867PVGCyTdzqpz0izu5ZjQ==",
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@hono/node-server": "^1.19.9",
         "ajv": "^8.17.1",
@@ -2653,6 +2782,19 @@
         }
       }
     },
+    "node_modules/@modelcontextprotocol/server": {
+      "version": "2.0.0-beta.4",
+      "resolved": "https://registry.npmjs.org/@modelcontextprotocol/server/-/server-2.0.0-beta.4.tgz",
+      "integrity": "sha512-pjMZcNEt1dOq0aJCcY3b7w1Ayh+qmQN2xlfTELcGV9yiAjEGIczBPBLWWW0k0zzo5T8kiv15jtKPsWeHGxLvLg==",
+      "license": "MIT",
+      "dependencies": {
+        "@modelcontextprotocol/core": "2.0.0-beta.4",
+        "zod": "^4.2.0"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
     "node_modules/@modelcontextprotocol/server-basic-preact": {
       "resolved": "examples/basic-server-preact",
       "link": true
@@ -4264,6 +4406,7 @@
       "resolved": "https://registry.npmjs.org/ajv/-/ajv-8.18.0.tgz",
       "integrity": "sha512-PlXPeEWMXMZ7sPYOHqmDyCJzcfNrUr3fGNKtezX14ykXOEIvyK81d+qydx89KY5O71FKMPaQ2vBfBFI5NHR63A==",
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "fast-deep-equal": "^3.1.3",
         "fast-uri": "^3.0.1",
@@ -4280,6 +4423,7 @@
       "resolved": "https://registry.npmjs.org/ajv-formats/-/ajv-formats-3.0.1.tgz",
       "integrity": "sha512-8iUql50EUR+uUcdRQ3HDqa6EVyo3docL8g5WJ3FNcWmu62IbkGUue/pEyLBW8VGKKucTPgqeks4fIU1DA4yowQ==",
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "ajv": "^8.0.0"
       },
@@ -5815,6 +5959,7 @@
       "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-8.5.2.tgz",
       "integrity": "sha512-5Kb34ipNX694DH48vN9irak1Qx30nb0PLYHXfJgw4YEjiC3ZEmZJhwOp+VfiCYwFzvFTdB9QkArYS5kXa2cx2A==",
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "ip-address": "^10.2.0"
       },
@@ -5832,7 +5977,8 @@
       "version": "3.1.3",
       "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",
       "integrity": "sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q==",
-      "license": "MIT"
+      "license": "MIT",
+      "peer": true
     },
     "node_modules/fast-uri": {
       "version": "3.1.2",
@@ -5848,7 +5994,8 @@
           "url": "https://opencollective.com/fastify"
         }
       ],
-      "license": "BSD-3-Clause"
+      "license": "BSD-3-Clause",
+      "peer": true
     },
     "node_modules/fflate": {
       "version": "0.8.2",
@@ -6175,6 +6322,7 @@
       "resolved": "https://registry.npmjs.org/hono/-/hono-4.12.23.tgz",
       "integrity": "sha512-eIaZ9qDgu7XV0pxOCrg7/WhnQ6Ivm22UcxhXx/A3dcbqbbYgBEkc6e/J/s7j2tS96zoB0S9VBdLwQNCWwUo4LA==",
       "license": "MIT",
+      "peer": true,
       "engines": {
         "node": ">=16.9.0"
       }
@@ -6316,6 +6464,7 @@
       "resolved": "https://registry.npmjs.org/ip-address/-/ip-address-10.2.0.tgz",
       "integrity": "sha512-/+S6j4E9AHvW9SWMSEY9Xfy66O5PWvVEJ08O0y5JGyEKQpojb0K0GKpz/v5HJ/G0vi3D2sjGK78119oXZeE0qA==",
       "license": "MIT",
+      "peer": true,
       "engines": {
         "node": ">= 12"
       }
@@ -6511,13 +6660,15 @@
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/json-schema-traverse/-/json-schema-traverse-1.0.0.tgz",
       "integrity": "sha512-NM8/P9n3XjXhIZn1lLhkFaACTOURQXjWhV4BA/RnOv8xvgqtqpAX9IO4mRQxSx1Rlo4tqzeqb0sOlruaOy3dug==",
-      "license": "MIT"
+      "license": "MIT",
+      "peer": true
     },
     "node_modules/json-schema-typed": {
       "version": "8.0.2",
       "resolved": "https://registry.npmjs.org/json-schema-typed/-/json-schema-typed-8.0.2.tgz",
       "integrity": "sha512-fQhoXdcvc3V28x7C7BMs4P5+kNlgUURe2jmUT1T//oBRMDrqy1QPelJimwZGo7Hg9VPV3EQV5Bnq4hbFy2vetA==",
-      "license": "BSD-2-Clause"
+      "license": "BSD-2-Clause",
+      "peer": true
     },
     "node_modules/json5": {
       "version": "2.2.3",
@@ -7493,6 +7644,7 @@
       "resolved": "https://registry.npmjs.org/require-from-string/-/require-from-string-2.0.2.tgz",
       "integrity": "sha512-Xf0nWe6RseziFMu+Ap9biiUbmplq6S9/p+7w7YXP/JBHhrUDDUhwa+vANyubuqfZWTveU//DYVGsDG7RKL/vEw==",
       "license": "MIT",
+      "peer": true,
       "engines": {
         "node": ">=0.10.0"
       }
@@ -9619,6 +9771,7 @@
       "resolved": "https://registry.npmjs.org/zod-to-json-schema/-/zod-to-json-schema-3.25.1.tgz",
       "integrity": "sha512-pM/SU9d3YAggzi6MtR4h7ruuQlqKtad8e9S0fmxcMi+ueAK5Korys/aWcV9LIIHTVbj01NdzxcnXSN+O74ZIVA==",
       "license": "ISC",
+      "peer": true,
       "peerDependencies": {
         "zod": "^3.25 || ^4"
       }
diff --git a/package.json b/package.json
index 8c6ead57b..ecbf386a8 100644
--- a/package.json
+++ b/package.json
@@ -77,7 +77,9 @@
   "author": "Olivier Chafik",
   "devDependencies": {
     "@boneskull/typedoc-plugin-mermaid": "^0.2.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
+    "@modelcontextprotocol/core": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "@playwright/test": "1.57.0",
     "@types/bun": "^1.3.2",
     "@types/node": "20.19.27",
@@ -105,13 +107,15 @@
     "typedoc": "^0.28.14",
     "typedoc-github-theme": "^0.4.0",
     "typescript": "^5.9.3",
-    "zod": "^4.1.13"
+    "zod": "^4.2.0"
   },
   "peerDependencies": {
-    "@modelcontextprotocol/sdk": "^1.29.0",
+    "@modelcontextprotocol/client": "2.0.0-beta.4",
+    "@modelcontextprotocol/core": "2.0.0-beta.4",
+    "@modelcontextprotocol/server": "2.0.0-beta.4",
     "react": "^17.0.0 || ^18.0.0 || ^19.0.0",
     "react-dom": "^17.0.0 || ^18.0.0 || ^19.0.0",
-    "zod": "^3.25.0 || ^4.0.0"
+    "zod": "^4.2.0"
   },
   "peerDependenciesMeta": {
     "react": {
diff --git a/plugins/mcp-apps/skills/add-app-to-server/SKILL.md b/plugins/mcp-apps/skills/add-app-to-server/SKILL.md
index 02d09a4e2..69e41f836 100644
--- a/plugins/mcp-apps/skills/add-app-to-server/SKILL.md
+++ b/plugins/mcp-apps/skills/add-app-to-server/SKILL.md
@@ -77,13 +77,15 @@ Before writing any code, analyze the server's existing tools and determine which
 ## Step 2: Add Dependencies
 
 ```bash
-npm install @modelcontextprotocol/ext-apps
+npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/client@2.0.0-beta.4 @modelcontextprotocol/core@2.0.0-beta.4 @modelcontextprotocol/server@2.0.0-beta.4 zod@^4.2.0
 npm install -D vite vite-plugin-singlefile
 ```
 
 Plus framework-specific dependencies if needed (e.g., `react`, `react-dom`, `@vitejs/plugin-react` for React).
 
-Use `npm install` to add dependencies rather than manually writing version numbers. This lets npm resolve the latest compatible versions. Never specify version numbers from memory.
+Use the exact base MCP SDK prerelease required by ext-apps. Existing servers
+that still import `@modelcontextprotocol/sdk` v1 must migrate those imports and
+handler schemas before adding the App integration.
 
 ## Step 3: Set Up the Build Pipeline
 
@@ -146,10 +148,14 @@ Transform plain MCP tools into App tools with UI.
 
 **Before** (plain MCP tool):
 ```typescript
-server.tool("my-tool", { param: z.string() }, async (args) => {
-  const data = await fetchData(args.param);
-  return { content: [{ type: "text", text: JSON.stringify(data) }] };
-});
+server.registerTool(
+  "my-tool",
+  { inputSchema: z.object({ param: z.string() }) },
+  async ({ param }) => {
+    const data = await fetchData(param);
+    return { content: [{ type: "text", text: JSON.stringify(data) }] };
+  },
+);
 ```
 
 **After** (App tool with UI):
@@ -158,17 +164,22 @@ import { registerAppTool, registerAppResource, RESOURCE_MIME_TYPE } from "@model
 
 const resourceUri = "ui://my-tool/mcp-app.html";
 
-registerAppTool(server, "my-tool", {
-  description: "Shows data with an interactive UI",
-  inputSchema: { param: z.string() },
-  _meta: { ui: { resourceUri } },
-}, async (args) => {
-  const data = await fetchData(args.param);
-  return {
-    content: [{ type: "text", text: JSON.stringify(data) }],   // text fallback for non-UI hosts
-    structuredContent: { data },                                 // structured data for the UI
-  };
-});
+registerAppTool(
+  server,
+  "my-tool",
+  {
+    description: "Shows data with an interactive UI",
+    inputSchema: z.object({ param: z.string() }),
+    _meta: { ui: { resourceUri } },
+  },
+  async ({ param }) => {
+    const data = await fetchData(param);
+    return {
+      content: [{ type: "text", text: JSON.stringify(data) }], // text fallback for non-UI hosts
+      structuredContent: { data }, // structured data for the UI
+    };
+  },
+);
 ```
 
 Key guidance:
@@ -187,17 +198,21 @@ import path from "node:path";
 
 const resourceUri = "ui://my-tool/mcp-app.html";
 
-registerAppResource(server, {
-  uri: resourceUri,
-  name: "My Tool UI",
-  mimeType: RESOURCE_MIME_TYPE,
-}, async () => {
-  const html = await fs.readFile(
-    path.resolve(import.meta.dirname, "dist", "mcp-app.html"),
-    "utf-8",
-  );
-  return { contents: [{ uri: resourceUri, mimeType: RESOURCE_MIME_TYPE, text: html }] };
-});
+registerAppResource(
+  server,
+  "My Tool UI",
+  resourceUri,
+  {},
+  async () => {
+    const html = await fs.readFile(
+      path.resolve(import.meta.dirname, "dist", "mcp-app.html"),
+      "utf-8",
+    );
+    return {
+      contents: [{ uri: resourceUri, mimeType: RESOURCE_MIME_TYPE, text: html }],
+    };
+  },
+);
 ```
 
 If multiple tools share the same UI, they can reference the same `resourceUri` and the same resource registration.
@@ -271,25 +286,32 @@ registerAppTool(server, "poll-data", {
 });
 ```
 
-The UI calls these via `app.callServerTool("poll-data", {})`.
+The UI calls these via
+`app.callServerTool({ name: "poll-data", arguments: {} })`.
 
 ### CSP Configuration
 
 If the UI needs to load external resources (fonts, APIs, CDNs), declare the domains:
 
 ```typescript
-registerAppResource(server, {
-  uri: resourceUri,
-  name: "My Tool UI",
-  mimeType: RESOURCE_MIME_TYPE,
-  _meta: {
-    ui: {
-      connectDomains: ["api.example.com"],      // fetch/XHR targets
-      resourceDomains: ["cdn.example.com"],      // scripts, styles, images
-      frameDomains: ["embed.example.com"],        // nested iframes
+registerAppResource(server, "My Tool UI", resourceUri, {}, async () => ({
+  contents: [
+    {
+      uri: resourceUri,
+      mimeType: RESOURCE_MIME_TYPE,
+      text: html,
+      _meta: {
+        ui: {
+          csp: {
+            connectDomains: ["https://api.example.com"], // fetch/XHR targets
+            resourceDomains: ["https://cdn.example.com"], // scripts, styles, images
+            frameDomains: ["https://embed.example.com"], // nested iframes
+          },
+        },
+      },
     },
-  },
-}, async () => { /* ... */ });
+  ],
+}));
 ```
 
 ### Streaming Partial Input
@@ -326,7 +348,14 @@ server.server.oninitialized = () => {
     }, appToolHandler);
   } else {
     // Text-only client — register plain tool
-    server.tool("my-tool", "Shows data", { param: z.string() }, plainToolHandler);
+    server.registerTool(
+      "my-tool",
+      {
+        description: "Shows data",
+        inputSchema: z.object({ param: z.string() }),
+      },
+      plainToolHandler,
+    );
   }
 };
 ```
diff --git a/plugins/mcp-apps/skills/convert-web-app/SKILL.md b/plugins/mcp-apps/skills/convert-web-app/SKILL.md
index 5db2d946c..22686ef5e 100644
--- a/plugins/mcp-apps/skills/convert-web-app/SKILL.md
+++ b/plugins/mcp-apps/skills/convert-web-app/SKILL.md
@@ -115,19 +115,20 @@ Create a new MCP server with tool and resource registration. This wraps the exis
 ### Dependencies
 
 ```bash
-npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/sdk zod
+npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/client@2.0.0-beta.4 @modelcontextprotocol/core@2.0.0-beta.4 @modelcontextprotocol/server@2.0.0-beta.4 zod@^4.2.0
 npm install -D tsx vite vite-plugin-singlefile
 ```
 
-Use `npm install` to add dependencies rather than manually writing version numbers. This lets npm resolve the latest compatible versions. Never specify version numbers from memory.
+Use `npm install` with the exact base MCP SDK prerelease required by ext-apps.
+Do not substitute unpublished local packages or guess a different prerelease.
 
 ### Server Code
 
 Create `server.ts`:
 
 ```typescript
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
+import { McpServer } from "@modelcontextprotocol/server";
+import { StdioServerTransport } from "@modelcontextprotocol/server/stdio";
 import { registerAppTool, registerAppResource, RESOURCE_MIME_TYPE } from "@modelcontextprotocol/ext-apps/server";
 import fs from "node:fs/promises";
 import path from "node:path";
@@ -140,7 +141,9 @@ const resourceUri = "ui://my-app/mcp-app.html";
 // Register the tool — inputSchema maps to the app's data sources
 registerAppTool(server, "show-app", {
   description: "Displays the app with the given parameters",
-  inputSchema: { query: z.string().describe("The search query") },
+  inputSchema: z.object({
+    query: z.string().describe("The search query"),
+  }),
   _meta: { ui: { resourceUri } },
 }, async (args) => {
   // Process args server-side if needed
@@ -151,19 +154,29 @@ registerAppTool(server, "show-app", {
 });
 
 // Register the HTML resource
-registerAppResource(server, {
-  uri: resourceUri,
-  name: "My App UI",
-  mimeType: RESOURCE_MIME_TYPE,
-  // Add CSP domains from Step 2 if needed:
-  // _meta: { ui: { connectDomains: ["api.example.com"], resourceDomains: ["cdn.example.com"] } },
-}, async () => {
-  const html = await fs.readFile(
-    path.resolve(import.meta.dirname, "dist", "mcp-app.html"),
-    "utf-8",
-  );
-  return { contents: [{ uri: resourceUri, mimeType: RESOURCE_MIME_TYPE, text: html }] };
-});
+registerAppResource(
+  server,
+  "My App UI",
+  resourceUri,
+  {},
+  async () => {
+    const html = await fs.readFile(
+      path.resolve(import.meta.dirname, "dist", "mcp-app.html"),
+      "utf-8",
+    );
+    return {
+      contents: [
+        {
+          uri: resourceUri,
+          mimeType: RESOURCE_MIME_TYPE,
+          text: html,
+          // Add CSP domains from Step 2 if needed:
+          // _meta: { ui: { csp: { connectDomains: ["https://api.example.com"], resourceDomains: ["https://cdn.example.com"] } } },
+        },
+      ],
+    };
+  },
+);
 
 // Start the server
 const transport = new StdioServerTransport();
@@ -310,7 +323,10 @@ const data = await fetch("/api/data").then(r => r.json());
 // After (hybrid):
 async function fetchData(): Promise<any> {
   if (isMcpApp) {
-    const result = await app.callServerTool("fetch-data", {});
+    const result = await app.callServerTool({
+      name: "fetch-data",
+      arguments: {},
+    });
     return result.structuredContent;
   }
   return fetch("/api/data").then(r => r.json());
@@ -437,7 +453,8 @@ registerAppTool(server, "refresh-data", {
 });
 ```
 
-The UI calls these via `app.callServerTool("refresh-data", {})`.
+The UI calls these via
+`app.callServerTool({ name: "refresh-data", arguments: {} })`.
 
 ### Streaming Partial Input
 
diff --git a/plugins/mcp-apps/skills/create-mcp-app/SKILL.md b/plugins/mcp-apps/skills/create-mcp-app/SKILL.md
index 5bd12191d..fc41e70cd 100644
--- a/plugins/mcp-apps/skills/create-mcp-app/SKILL.md
+++ b/plugins/mcp-apps/skills/create-mcp-app/SKILL.md
@@ -110,11 +110,12 @@ See `/tmp/mcp-ext-apps/docs/patterns.md` for detailed recipes:
 **Always** use `npm install` to add dependencies rather than manually writing version numbers:
 
 ```bash
-npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/sdk zod express cors
+npm install @modelcontextprotocol/ext-apps @modelcontextprotocol/client@2.0.0-beta.4 @modelcontextprotocol/core@2.0.0-beta.4 @modelcontextprotocol/server@2.0.0-beta.4 @modelcontextprotocol/node@2.0.0-beta.4 @modelcontextprotocol/express@2.0.0-beta.4 zod@^4.2.0 express cors
 npm install -D typescript vite vite-plugin-singlefile concurrently cross-env @types/node @types/express @types/cors
 ```
 
-This lets npm resolve the latest compatible versions. **Never** specify version numbers from memory.
+Use the exact base MCP SDK prerelease required by ext-apps. Do not substitute
+unpublished local packages or guess a different prerelease.
 
 ### TypeScript Server Execution
 
diff --git a/scripts/generate-schemas.ts b/scripts/generate-schemas.ts
index 109f35247..85225f5c5 100644
--- a/scripts/generate-schemas.ts
+++ b/scripts/generate-schemas.ts
@@ -12,7 +12,7 @@
  *
  * ts-to-zod generates `import { z } from "zod"`. We rewrite this to
  * `import { z } from "zod/v4"` because the generated schemas compose with
- * schemas imported from `@modelcontextprotocol/sdk/types.js`, which the SDK
+ * schemas imported from `@modelcontextprotocol/core`, which the SDK
  * constructs via `zod/v4`. Mixing schemas from the v3 and v4 APIs at runtime
  * fails with errors like `keyValidator._parse is not a function` (v3 internals
  * calling into v4 objects, or vice versa). The `zod/v4` subpath is exported by
@@ -22,7 +22,7 @@
  *
  * **Problem**: ts-to-zod cannot resolve types imported from external packages.
  * When it encounters types like `ContentBlock`, `CallToolResult`, `Implementation`,
- * `RequestId`, and `Tool` from `@modelcontextprotocol/sdk`, it generates `z.any()`
+ * `RequestId`, and `Tool` from `@modelcontextprotocol/core`, it generates `z.any()`
  * as a placeholder.
  *
  * **Solution**: Import the schemas from MCP SDK and remove the z.any() placeholders.
@@ -193,7 +193,7 @@ function postProcess(content: string): string {
     `import { z } from "zod/v4";
 import {
   ${mcpImports},
-} from "@modelcontextprotocol/sdk/types.js";`,
+} from "@modelcontextprotocol/core";`,
   );
 
   // 2. Remove z.any() placeholders for external types (now imported from MCP SDK)
diff --git a/scripts/typedoc-plugin-base-sdk-links.mjs b/scripts/typedoc-plugin-base-sdk-links.mjs
new file mode 100644
index 000000000..609891828
--- /dev/null
+++ b/scripts/typedoc-plugin-base-sdk-links.mjs
@@ -0,0 +1,16 @@
+/**
+ * Resolve module-local links inherited from the base MCP SDK declarations.
+ *
+ * TypeDoc's externalSymbolLinkMappings handles package-qualified symbols, but
+ * the base SDK writes this particular reference as `index.inputRequired`.
+ */
+
+const BASE_SDK_DOCS = "https://ts.sdk.modelcontextprotocol.io/v2/";
+
+/** @param {import("typedoc").Application} app */
+export function load(app) {
+  app.converter.addUnknownSymbolResolver((ref) => {
+    const name = ref.symbolReference?.path?.map((part) => part.path).join(".");
+    if (name === "index.inputRequired") return BASE_SDK_DOCS;
+  });
+}
diff --git a/src/app-bridge.examples.ts b/src/app-bridge.examples.ts
index d5dc5bc74..47ad6234f 100644
--- a/src/app-bridge.examples.ts
+++ b/src/app-bridge.examples.ts
@@ -7,17 +7,11 @@
  * @module
  */
 
-import { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import type { Transport } from "@modelcontextprotocol/sdk/shared/transport.js";
-import {
-  CallToolResult,
-  CallToolResultSchema,
+import { Client, type Transport } from "@modelcontextprotocol/client";
+import type {
   CreateMessageRequest,
   CreateMessageResult,
-  ListResourcesResultSchema,
-  ReadResourceResultSchema,
-  ListPromptsResultSchema,
-} from "@modelcontextprotocol/sdk/types.js";
+} from "@modelcontextprotocol/server";
 import { AppBridge, PostMessageTransport } from "./app-bridge.js";
 import type { McpUiDisplayMode } from "./types.js";
 
@@ -223,8 +217,7 @@ function AppBridge_oncalltool_forwardToServer(
   bridge.oncalltool = async (params, extra) => {
     return mcpClient.request(
       { method: "tools/call", params },
-      CallToolResultSchema,
-      { signal: extra.signal },
+      { signal: extra.mcpReq.signal },
     );
   };
   //#endregion AppBridge_oncalltool_forwardToServer
@@ -245,7 +238,9 @@ function AppBridge_oncreatesamplingmessage_forwardToLlm(
   //#region AppBridge_oncreatesamplingmessage_forwardToLlm
   bridge.oncreatesamplingmessage = async (params, extra) => {
     // Apply rate limiting, user approval, cost controls here
-    return await myLlmProvider.complete(params, { signal: extra.signal });
+    return await myLlmProvider.complete(params, {
+      signal: extra.mcpReq.signal,
+    });
   };
   //#endregion AppBridge_oncreatesamplingmessage_forwardToLlm
 }
@@ -261,8 +256,7 @@ function AppBridge_onlistresources_returnResources(
   bridge.onlistresources = async (params, extra) => {
     return mcpClient.request(
       { method: "resources/list", params },
-      ListResourcesResultSchema,
-      { signal: extra.signal },
+      { signal: extra.mcpReq.signal },
     );
   };
   //#endregion AppBridge_onlistresources_returnResources
@@ -279,8 +273,7 @@ function AppBridge_onreadresource_returnResource(
   bridge.onreadresource = async (params, extra) => {
     return mcpClient.request(
       { method: "resources/read", params },
-      ReadResourceResultSchema,
-      { signal: extra.signal },
+      { signal: extra.mcpReq.signal },
     );
   };
   //#endregion AppBridge_onreadresource_returnResource
@@ -297,8 +290,7 @@ function AppBridge_onlistprompts_returnPrompts(
   bridge.onlistprompts = async (params, extra) => {
     return mcpClient.request(
       { method: "prompts/list", params },
-      ListPromptsResultSchema,
-      { signal: extra.signal },
+      { signal: extra.mcpReq.signal },
     );
   };
   //#endregion AppBridge_onlistprompts_returnPrompts
@@ -444,10 +436,10 @@ async function AppBridge_sendToolResult_afterExecution(
   args: Record<string, unknown>,
 ) {
   //#region AppBridge_sendToolResult_afterExecution
-  const result = await mcpClient.request(
-    { method: "tools/call", params: { name: "get_weather", arguments: args } },
-    CallToolResultSchema,
-  );
+  const result = await mcpClient.request({
+    method: "tools/call",
+    params: { name: "get_weather", arguments: args },
+  });
   bridge.sendToolResult(result);
   //#endregion AppBridge_sendToolResult_afterExecution
 }
diff --git a/src/app-bridge.test.ts b/src/app-bridge.test.ts
index a4fe1de1e..81e072fd6 100644
--- a/src/app-bridge.test.ts
+++ b/src/app-bridge.test.ts
@@ -1,17 +1,6 @@
 import { describe, it, expect, beforeEach, afterEach, spyOn } from "bun:test";
-import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
-import type { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import type { ServerCapabilities } from "@modelcontextprotocol/sdk/types.js";
-import {
-  EmptyResultSchema,
-  ListPromptsResultSchema,
-  ListResourcesResultSchema,
-  ListResourceTemplatesResultSchema,
-  PromptListChangedNotificationSchema,
-  ReadResourceResultSchema,
-  ResourceListChangedNotificationSchema,
-  ToolListChangedNotificationSchema,
-} from "@modelcontextprotocol/sdk/types.js";
+import { Client, InMemoryTransport } from "@modelcontextprotocol/client";
+import { Server, type ServerCapabilities } from "@modelcontextprotocol/server";
 import { z } from "zod/v4";
 
 import { App } from "./app";
@@ -22,6 +11,7 @@ import {
   getToolUiResourceUri,
   isToolVisibilityModelOnly,
   isToolVisibilityAppOnly,
+  McpUiOpenLinkResultSchema,
   type McpUiHostCapabilities,
 } from "./app-bridge";
 
@@ -34,11 +24,18 @@ const flush = () => new Promise((resolve) => setTimeout(resolve, 0));
  */
 function createMockClient(
   serverCapabilities: ServerCapabilities = {},
-): Pick<Client, "getServerCapabilities" | "request" | "notification"> {
+): Pick<
+  Client,
+  | "getServerCapabilities"
+  | "request"
+  | "notification"
+  | "setNotificationHandler"
+> {
   return {
     getServerCapabilities: () => serverCapabilities,
     request: async () => ({}) as never,
     notification: async () => {},
+    setNotificationHandler: () => {},
   };
 }
 
@@ -85,6 +82,58 @@ describe("App <-> AppBridge integration", () => {
       expect(initializedFired).toBe(true);
     });
 
+    it("keeps standard initialization separate from the Apps-ready gate", async () => {
+      const methods: string[] = [];
+      let releaseAppsInitialized!: () => void;
+      let reachedAppsInitialized!: () => void;
+      const appsInitializedGate = new Promise<void>((resolve) => {
+        releaseAppsInitialized = resolve;
+      });
+      const reachedGate = new Promise<void>((resolve) => {
+        reachedAppsInitialized = resolve;
+      });
+      const originalSend = appTransport.send.bind(appTransport);
+      appTransport.send = async (message, options) => {
+        if ("method" in message) methods.push(message.method);
+        if (
+          "method" in message &&
+          message.method === "ui/notifications/initialized"
+        ) {
+          reachedAppsInitialized();
+          await appsInitializedGate;
+        }
+        return originalSend(message, options);
+      };
+
+      let singularCalls = 0;
+      let listenerCalls = 0;
+      bridge.oninitialized = () => singularCalls++;
+      bridge.addEventListener("initialized", () => listenerCalls++);
+
+      await bridge.connect(bridgeTransport);
+      const connecting = app.connect(appTransport);
+      await reachedGate;
+
+      expect(methods).toEqual([
+        "initialize",
+        "notifications/initialized",
+        "ui/initialize",
+        "ui/notifications/initialized",
+      ]);
+      expect(app.getNegotiatedProtocolVersion()).toBe("2025-11-25");
+      expect(bridge.getNegotiatedProtocolVersion()).toBe("2025-11-25");
+      expect(bridge.getClientVersion()).toEqual(testAppInfo);
+      expect(bridge.getAppVersion()).toEqual(testAppInfo);
+      expect(singularCalls).toBe(0);
+      expect(listenerCalls).toBe(0);
+
+      releaseAppsInitialized();
+      await connecting;
+
+      expect(singularCalls).toBe(1);
+      expect(listenerCalls).toBe(1);
+    });
+
     it("App receives host info and capabilities after connect", async () => {
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
@@ -94,6 +143,8 @@ describe("App <-> AppBridge integration", () => {
 
       const hostCaps = app.getHostCapabilities();
       expect(hostCaps).toEqual(testHostCapabilities);
+      expect(bridge.getHostCapabilities()).toEqual(testHostCapabilities);
+      expect(bridge.getCapabilities()).toEqual({});
     });
 
     it("Bridge receives app info and capabilities after initialization", async () => {
@@ -614,6 +665,30 @@ describe("App <-> AppBridge integration", () => {
 
       expect(result.isError).toBe(true);
     });
+
+    it("rejects invalid params for a custom ui request", async () => {
+      bridge.onopenlink = async () => ({});
+      await app.connect(appTransport);
+
+      await expect(
+        app.request(
+          {
+            method: "ui/open-link",
+            params: { url: 42 },
+          },
+          McpUiOpenLinkResultSchema,
+        ),
+      ).rejects.toThrow();
+    });
+
+    it("rejects invalid results from a custom ui handler", async () => {
+      bridge.onopenlink = async () => ({ isError: "yes" }) as never;
+      await app.connect(appTransport);
+
+      await expect(
+        app.openLink({ url: "https://example.com" }),
+      ).rejects.toThrow();
+    });
   });
 
   describe("deprecated method aliases", () => {
@@ -683,10 +758,7 @@ describe("App <-> AppBridge integration", () => {
       await app.connect(appTransport);
 
       // Bridge can send ping via the protocol's request method
-      const result = await bridge.request(
-        { method: "ping", params: {} },
-        EmptyResultSchema,
-      );
+      const result = await bridge.request({ method: "ping", params: {} });
 
       expect(result).toEqual({});
     });
@@ -801,7 +873,7 @@ describe("App <-> AppBridge integration", () => {
       });
       await bridge.callTool({ name: "noargs", arguments: {} });
       expect(receivedExtra).toBeDefined();
-      expect(receivedExtra.signal).toBeInstanceOf(AbortSignal);
+      expect(receivedExtra.mcpReq.signal).toBeInstanceOf(AbortSignal);
     });
 
     it("isError result skips output schema validation", async () => {
@@ -2183,10 +2255,10 @@ describe("App <-> AppBridge integration", () => {
       await app.connect(appTransport);
 
       // App sends resources/list request via the protocol's request method
-      const result = await app.request(
-        { method: "resources/list", params: requestParams },
-        ListResourcesResultSchema,
-      );
+      const result = await app.request({
+        method: "resources/list",
+        params: requestParams,
+      });
 
       expect(receivedRequests).toHaveLength(1);
       expect(receivedRequests[0]).toMatchObject(requestParams);
@@ -2227,10 +2299,10 @@ describe("App <-> AppBridge integration", () => {
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
 
-      const result = await app.request(
-        { method: "resources/read", params: requestParams },
-        ReadResourceResultSchema,
-      );
+      const result = await app.request({
+        method: "resources/read",
+        params: requestParams,
+      });
 
       expect(receivedRequests).toHaveLength(1);
       expect(receivedRequests[0]).toMatchObject(requestParams);
@@ -2278,10 +2350,10 @@ describe("App <-> AppBridge integration", () => {
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
 
-      const result = await app.request(
-        { method: "resources/templates/list", params: requestParams },
-        ListResourceTemplatesResultSchema,
-      );
+      const result = await app.request({
+        method: "resources/templates/list",
+        params: requestParams,
+      });
 
       expect(receivedRequests).toHaveLength(1);
       expect(receivedRequests[0]).toMatchObject(requestParams);
@@ -2301,10 +2373,10 @@ describe("App <-> AppBridge integration", () => {
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
 
-      const result = await app.request(
-        { method: "prompts/list", params: requestParams },
-        ListPromptsResultSchema,
-      );
+      const result = await app.request({
+        method: "prompts/list",
+        params: requestParams,
+      });
 
       expect(receivedRequests).toHaveLength(1);
       expect(receivedRequests[0]).toMatchObject(requestParams);
@@ -2313,9 +2385,13 @@ describe("App <-> AppBridge integration", () => {
 
     it("sendToolListChanged sends notification to app", async () => {
       const receivedNotifications: unknown[] = [];
-      app.setNotificationHandler(ToolListChangedNotificationSchema, (n) => {
-        receivedNotifications.push(n.params);
-      });
+      bridge.oncalltool = async () => ({ content: [] });
+      app.setNotificationHandler(
+        "notifications/tools/list_changed",
+        (notification) => {
+          receivedNotifications.push(notification.params);
+        },
+      );
 
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
@@ -2328,9 +2404,13 @@ describe("App <-> AppBridge integration", () => {
 
     it("sendResourceListChanged sends notification to app", async () => {
       const receivedNotifications: unknown[] = [];
-      app.setNotificationHandler(ResourceListChangedNotificationSchema, (n) => {
-        receivedNotifications.push(n.params);
-      });
+      bridge.onlistresources = async () => ({ resources: [] });
+      app.setNotificationHandler(
+        "notifications/resources/list_changed",
+        (notification) => {
+          receivedNotifications.push(notification.params);
+        },
+      );
 
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
@@ -2343,9 +2423,13 @@ describe("App <-> AppBridge integration", () => {
 
     it("sendPromptListChanged sends notification to app", async () => {
       const receivedNotifications: unknown[] = [];
-      app.setNotificationHandler(PromptListChangedNotificationSchema, (n) => {
-        receivedNotifications.push(n.params);
-      });
+      bridge.onlistprompts = async () => ({ prompts: [] });
+      app.setNotificationHandler(
+        "notifications/prompts/list_changed",
+        (notification) => {
+          receivedNotifications.push(notification.params);
+        },
+      );
 
       await bridge.connect(bridgeTransport);
       await app.connect(appTransport);
@@ -2358,6 +2442,184 @@ describe("App <-> AppBridge integration", () => {
   });
 });
 
+describe("AppBridge outer v2 Client proxy", () => {
+  let outerClient: Client;
+  let outerServer: Server;
+  let outerClientTransport: InMemoryTransport;
+  let outerServerTransport: InMemoryTransport;
+  let outerInitializeCount: number;
+
+  beforeEach(async () => {
+    [outerClientTransport, outerServerTransport] =
+      InMemoryTransport.createLinkedPair();
+    outerInitializeCount = 0;
+    const originalSend = outerClientTransport.send.bind(outerClientTransport);
+    outerClientTransport.send = async (message, options) => {
+      if ("method" in message && message.method === "initialize") {
+        outerInitializeCount++;
+      }
+      return originalSend(message, options);
+    };
+
+    outerServer = new Server(
+      { name: "ActualServer", version: "1.0.0" },
+      {
+        capabilities: {
+          tools: { listChanged: true },
+          resources: { listChanged: true },
+          prompts: { listChanged: true },
+        },
+        supportedProtocolVersions: ["2025-11-25"],
+      },
+    );
+    outerServer.setRequestHandler("tools/call", async (request) => ({
+      content: [
+        {
+          type: "text",
+          text: `outer:${request.params.name}`,
+        },
+      ],
+    }));
+
+    outerClient = new Client(
+      { name: "HostOuterClient", version: "1.0.0" },
+      {
+        capabilities: {},
+        versionNegotiation: { mode: "legacy" },
+        supportedProtocolVersions: ["2025-11-25"],
+      },
+    );
+    await outerServer.connect(outerServerTransport);
+    await outerClient.connect(outerClientTransport);
+  });
+
+  afterEach(async () => {
+    await outerClient.close().catch(() => {});
+    await outerServer.close().catch(() => {});
+  });
+
+  it("proxies through the outer Client without reconnecting it", async () => {
+    const bridge = new AppBridge(
+      outerClient,
+      testHostInfo,
+      testHostCapabilities,
+    );
+    const app = new App(testAppInfo, {}, { autoResize: false });
+    let [appTransport, bridgeTransport] = InMemoryTransport.createLinkedPair();
+
+    await bridge.connect(bridgeTransport);
+    await app.connect(appTransport);
+    expect(
+      await app.callServerTool({ name: "first", arguments: {} }),
+    ).toMatchObject({
+      content: [{ type: "text", text: "outer:first" }],
+    });
+    expect(outerInitializeCount).toBe(1);
+
+    await app.close();
+    await bridge.close();
+    [appTransport, bridgeTransport] = InMemoryTransport.createLinkedPair();
+    await bridge.connect(bridgeTransport);
+    await app.connect(appTransport);
+
+    expect(
+      await app.callServerTool({ name: "second", arguments: {} }),
+    ).toMatchObject({
+      content: [{ type: "text", text: "outer:second" }],
+    });
+    expect(outerInitializeCount).toBe(1);
+    expect(outerClient.getServerVersion()).toMatchObject({
+      name: "ActualServer",
+      version: "1.0.0",
+    });
+
+    await app.close();
+    await bridge.close();
+  });
+
+  it("propagates View cancellation to the actual outer Server", async () => {
+    let started!: () => void;
+    let aborted!: () => void;
+    const startedPromise = new Promise<void>((resolve) => {
+      started = resolve;
+    });
+    const abortedPromise = new Promise<void>((resolve) => {
+      aborted = resolve;
+    });
+    outerServer.setRequestHandler("tools/call", async (_request, context) => {
+      started();
+      await new Promise<void>((resolve) => {
+        context.mcpReq.signal.addEventListener(
+          "abort",
+          () => {
+            aborted();
+            resolve();
+          },
+          { once: true },
+        );
+      });
+      return { content: [] };
+    });
+
+    const bridge = new AppBridge(
+      outerClient,
+      testHostInfo,
+      testHostCapabilities,
+    );
+    const app = new App(testAppInfo, {}, { autoResize: false });
+    const [appTransport, bridgeTransport] =
+      InMemoryTransport.createLinkedPair();
+    await bridge.connect(bridgeTransport);
+    await app.connect(appTransport);
+
+    const controller = new AbortController();
+    const result = app.callServerTool(
+      { name: "cancel-me", arguments: {} },
+      { signal: controller.signal },
+    );
+    await startedPromise;
+    controller.abort("test cancellation");
+    await abortedPromise;
+    await expect(result).rejects.toThrow();
+
+    await app.close();
+    await bridge.close();
+  });
+
+  it("forwards outer list-changed notifications to the App", async () => {
+    const bridge = new AppBridge(
+      outerClient,
+      testHostInfo,
+      testHostCapabilities,
+    );
+    const app = new App(testAppInfo, {}, { autoResize: false });
+    const [appTransport, bridgeTransport] =
+      InMemoryTransport.createLinkedPair();
+    const received: string[] = [];
+    app.setNotificationHandler("notifications/tools/list_changed", () => {
+      received.push("tools");
+    });
+    app.setNotificationHandler("notifications/resources/list_changed", () => {
+      received.push("resources");
+    });
+    app.setNotificationHandler("notifications/prompts/list_changed", () => {
+      received.push("prompts");
+    });
+
+    await bridge.connect(bridgeTransport);
+    await app.connect(appTransport);
+    await outerServer.sendToolListChanged();
+    await outerServer.sendResourceListChanged();
+    await outerServer.sendPromptListChanged();
+    await flush();
+
+    expect(received).toEqual(["tools", "resources", "prompts"]);
+
+    await app.close();
+    await bridge.close();
+  });
+});
+
 describe("getToolUiResourceUri", () => {
   describe("new nested format (_meta.ui.resourceUri)", () => {
     it("extracts resourceUri from _meta.ui.resourceUri", () => {
@@ -2713,7 +2975,7 @@ describe("isToolVisibilityAppOnly", () => {
       expect(a).toEqual([]);
     });
 
-    it("App.onEventDispatch merges hostcontext before listeners fire", async () => {
+    it("App merges hostcontext before listeners fire", async () => {
       let seen: unknown;
       app.addEventListener("hostcontextchanged", () => {
         seen = app.getHostContext();
@@ -2752,38 +3014,16 @@ describe("isToolVisibilityAppOnly", () => {
       expect(app.onteardown).toBe(handler);
     });
 
-    it("direct setRequestHandler throws when called twice", () => {
+    it("direct setRequestHandler uses base SDK replacement semantics", () => {
       const bridge2 = new AppBridge(
         createMockClient() as Client,
         testHostInfo,
         testHostCapabilities,
       );
-      bridge2.setRequestHandler(
-        // @ts-expect-error — exercising throw path with raw schema
-        { shape: { method: { value: "test/method" } } },
-        () => ({}),
-      );
-      expect(() => {
-        bridge2.setRequestHandler(
-          // @ts-expect-error — exercising throw path with raw schema
-          { shape: { method: { value: "test/method" } } },
-          () => ({}),
-        );
-      }).toThrow(/already registered/);
-    });
-
-    it("direct setNotificationHandler throws for event-mapped methods", () => {
-      const app2 = new App(testAppInfo, {}, { autoResize: false });
-      app2.addEventListener("toolinput", () => {});
+      bridge2.setRequestHandler("ping", () => ({}));
       expect(() => {
-        app2.setNotificationHandler(
-          // @ts-expect-error — exercising throw path with raw schema
-          {
-            shape: { method: { value: "ui/notifications/tool-input" } },
-          },
-          () => {},
-        );
-      }).toThrow(/already registered/);
+        bridge2.setRequestHandler("ping", () => ({}));
+      }).not.toThrow();
     });
   });
 });
diff --git a/src/app-bridge.ts b/src/app-bridge.ts
index 23383c40f..d353cf71e 100644
--- a/src/app-bridge.ts
+++ b/src/app-bridge.ts
@@ -1,58 +1,51 @@
-import { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import { Transport } from "@modelcontextprotocol/sdk/shared/transport.js";
+import { type Client } from "@modelcontextprotocol/client";
 import {
-  CallToolRequest,
-  CallToolRequestSchema,
-  CallToolResult,
-  CallToolResultSchema,
-  CreateMessageRequest,
-  CreateMessageRequestSchema,
-  CreateMessageResult,
-  CreateMessageResultWithTools,
-  EmptyResult,
-  Implementation,
-  ListPromptsRequest,
-  ListPromptsRequestSchema,
-  ListPromptsResult,
-  ListPromptsResultSchema,
-  ListResourcesRequest,
-  ListResourcesRequestSchema,
-  ListResourcesResult,
-  ListResourcesResultSchema,
-  ListResourceTemplatesRequest,
-  ListResourceTemplatesRequestSchema,
-  ListResourceTemplatesResult,
-  ListResourceTemplatesResultSchema,
-  ListToolsRequest,
-  ListToolsRequestSchema,
-  ListToolsResultSchema,
-  LoggingMessageNotification,
-  LoggingMessageNotificationSchema,
-  PingRequest,
-  PingRequestSchema,
-  PromptListChangedNotification,
-  PromptListChangedNotificationSchema,
-  ReadResourceRequest,
-  ReadResourceRequestSchema,
-  ReadResourceResult,
-  ReadResourceResultSchema,
-  ResourceListChangedNotification,
-  ResourceListChangedNotificationSchema,
-  Tool,
-  ToolListChangedNotification,
-  ToolListChangedNotificationSchema,
-} from "@modelcontextprotocol/sdk/types.js";
+  Server,
+  type CallToolRequest,
+  type CallToolResult,
+  type CreateMessageRequest,
+  type CreateMessageResult,
+  type CreateMessageResultWithTools,
+  type EmptyResult,
+  type Implementation,
+  type JSONRPCRequest,
+  type ListPromptsRequest,
+  type ListPromptsResult,
+  type ListResourcesRequest,
+  type ListResourcesResult,
+  type ListResourceTemplatesRequest,
+  type ListResourceTemplatesResult,
+  type ListToolsRequest,
+  type LoggingMessageNotification,
+  type PingRequest,
+  type PromptListChangedNotification,
+  type ReadResourceRequest,
+  type ReadResourceResult,
+  type RequestOptions,
+  type ResourceListChangedNotification,
+  type Result,
+  type ServerCapabilities,
+  type ServerContext,
+  type ServerOptions,
+  type Tool,
+  type ToolListChangedNotification,
+  type Transport,
+} from "@modelcontextprotocol/server";
 import {
-  Protocol,
-  ProtocolOptions,
-  RequestOptions,
-} from "@modelcontextprotocol/sdk/shared/protocol.js";
-import { ProtocolWithEvents } from "./events";
+  EmptyResultSchema,
+  LoggingMessageNotificationSchema,
+} from "@modelcontextprotocol/core";
+import { EventDispatcher } from "./events";
+import type { ZodLiteral, ZodObject, ZodType } from "zod/v4";
+
+type MethodSchema = ZodObject<{
+  method: ZodLiteral<string>;
+  params: ZodType;
+}>;
+
+const INNER_MCP_PROTOCOL_VERSION = "2025-11-25";
 
 import {
-  type AppNotification,
-  type AppRequest,
-  type AppResult,
   type McpUiSandboxResourceReadyNotification,
   type McpUiSizeChangedNotification,
   type McpUiToolCancelledNotification,
@@ -71,15 +64,19 @@ import {
   McpUiInitializeRequest,
   McpUiInitializeRequestSchema,
   McpUiInitializeResult,
+  McpUiInitializeResultSchema,
   McpUiMessageRequest,
   McpUiMessageRequestSchema,
   McpUiMessageResult,
+  McpUiMessageResultSchema,
   McpUiOpenLinkRequest,
   McpUiOpenLinkRequestSchema,
   McpUiOpenLinkResult,
+  McpUiOpenLinkResultSchema,
   McpUiDownloadFileRequest,
   McpUiDownloadFileRequestSchema,
   McpUiDownloadFileResult,
+  McpUiDownloadFileResultSchema,
   McpUiResourceTeardownRequest,
   McpUiResourceTeardownResultSchema,
   McpUiRequestTeardownNotification,
@@ -90,6 +87,7 @@ import {
   McpUiRequestDisplayModeRequest,
   McpUiRequestDisplayModeRequestSchema,
   McpUiRequestDisplayModeResult,
+  McpUiRequestDisplayModeResultSchema,
   McpUiResourcePermissions,
   McpUiToolMeta,
 } from "./types";
@@ -98,6 +96,20 @@ export { RESOURCE_URI_META_KEY, RESOURCE_MIME_TYPE } from "./app";
 import { RESOURCE_URI_META_KEY } from "./app";
 export { PostMessageTransport } from "./message-transport";
 
+function proxiedInnerCapabilities(
+  capabilities: ServerCapabilities,
+): ServerCapabilities {
+  return {
+    ...(capabilities.tools && { tools: capabilities.tools }),
+    ...(capabilities.resources && {
+      resources: {
+        listChanged: capabilities.resources.listChanged,
+      },
+    }),
+    ...(capabilities.prompts && { prompts: capabilities.prompts }),
+  };
+}
+
 /**
  * Extract UI resource URI from tool metadata.
  *
@@ -203,10 +215,13 @@ export function buildAllowAttribute(
  *
  * @property hostContext - Optional initial host context to provide to the view
  *
- * @see `ProtocolOptions` from @modelcontextprotocol/sdk for available options
+ * @see `ServerOptions` from @modelcontextprotocol/server for available options
  * @see {@link McpUiHostContext `McpUiHostContext`} for the hostContext structure
  */
-export type HostOptions = ProtocolOptions & {
+export type HostOptions = Omit<
+  ServerOptions,
+  "capabilities" | "supportedProtocolVersions"
+> & {
   hostContext?: McpUiHostContext;
 };
 
@@ -221,15 +236,12 @@ export const SUPPORTED_PROTOCOL_VERSIONS = [LATEST_PROTOCOL_VERSION];
 /**
  * Extra metadata passed to request handlers.
  *
- * This type represents the additional context provided by the `Protocol` class
- * when handling requests, including abort signals and session information.
- * It is extracted from the MCP SDK's request handler signature.
+ * This type represents the additional context provided by the base MCP SDK
+ * `Server` when handling requests.
  *
  * @internal
  */
-type RequestHandlerExtra = Parameters<
-  Parameters<AppBridge["setRequestHandler"]>[1]
->[1];
+type RequestHandlerExtra = ServerContext;
 
 /**
  * Maps DOM-style event names to their notification `params` types.
@@ -249,7 +261,7 @@ export type AppBridgeEventMap = {
 /**
  * Host-side bridge for communicating with a single View ({@link app!App `App`}).
  *
- * `AppBridge` extends the MCP SDK's `Protocol` class and acts as a proxy between
+ * `AppBridge` extends the base MCP SDK's public `Server` class and acts as a proxy between
  * the host application and a view running in an iframe. When an MCP client
  * is provided to the constructor, it automatically forwards MCP server capabilities
  * (tools, resources, prompts) to the view. It also handles the initialization
@@ -303,47 +315,57 @@ export type AppBridgeEventMap = {
  * await bridge.connect(transport);
  * ```
  */
-export class AppBridge extends ProtocolWithEvents<
-  AppRequest,
-  AppNotification,
-  AppResult,
-  AppBridgeEventMap
-> {
+export class AppBridge extends Server {
   private _appCapabilities?: McpUiAppCapabilities;
   private _hostContext: McpUiHostContext = {};
   private _appInfo?: Implementation;
   private _initializedReceived = false;
+  private readonly _registeredEvents = new Set<keyof AppBridgeEventMap>();
+  private readonly _events = new EventDispatcher<AppBridgeEventMap>();
 
   /**
-   * Wrap every handler registered via `replaceRequestHandler` with a check
-   * that the View has sent `ui/notifications/initialized`. Warns (never
-   * throws) so lenient hosts keep working while still surfacing the
-   * misordering that leaves strict hosts with a permanently hidden iframe.
-   * `ui/initialize` and `ping` use `setRequestHandler` directly and are
-   * intentionally exempt.
+   * The base MCP SDK calls this hook for every standard and custom request
+   * handler registration. AppBridge uses it to preserve the existing warning
+   * when a View calls host methods before `ui/notifications/initialized`,
+   * without adding overload-forwarding adapters around `setRequestHandler`.
+   * Chaining through `super._wrapHandler()` retains the base `Server`'s own
+   * role-specific behavior, including tool-result validation. The two
+   * initialization methods and `ping` are exempt because they are valid before
+   * the Apps-ready gate. This wraps registered callbacks, not JSON-RPC dispatch.
    *
    * @see {@link https://github.com/anthropics/claude-ai-mcp/issues/149 claude-ai-mcp#149}
    */
-  private _baseReplaceRequestHandler = this.replaceRequestHandler;
-  protected override replaceRequestHandler: Protocol<
-    AppRequest,
-    AppNotification,
-    AppResult
-  >["setRequestHandler"] = (schema, handler) => {
-    this._baseReplaceRequestHandler(schema, (request, extra) => {
+  protected override _wrapHandler(
+    method: string,
+    handler: (
+      request: JSONRPCRequest,
+      context: ServerContext,
+    ) => Promise<Result>,
+  ): (request: JSONRPCRequest, context: ServerContext) => Promise<Result> {
+    const wrapped = super._wrapHandler(method, handler);
+    if (
+      method === "initialize" ||
+      method === "ui/initialize" ||
+      method === "ping"
+    ) {
+      return wrapped;
+    }
+    return async (request, context) => {
       if (!this._initializedReceived) {
         console.warn(
-          `[ext-apps] AppBridge received '${request.method}' before ` +
+          `[ext-apps] AppBridge received '${method}' before ` +
             `ui/notifications/initialized. The View is calling host ` +
             `methods before completing the handshake; it should await ` +
             `app.connect() first.`,
         );
       }
-      return handler(request, extra);
-    });
-  };
+      return wrapped(request, context);
+    };
+  }
 
-  protected readonly eventSchemas = {
+  private readonly eventSchemas: {
+    [K in keyof AppBridgeEventMap]: MethodSchema;
+  } = {
     sizechange: McpUiSizeChangedNotificationSchema,
     sandboxready: McpUiSandboxProxyReadyNotificationSchema,
     initialized: McpUiInitializedNotificationSchema,
@@ -351,6 +373,80 @@ export class AppBridge extends ProtocolWithEvents<
     loggingmessage: LoggingMessageNotificationSchema,
   };
 
+  protected setEventHandler<K extends keyof AppBridgeEventMap>(
+    event: K,
+    handler: ((params: AppBridgeEventMap[K]) => void) | undefined,
+  ): void {
+    this._ensureEventSlot(event);
+    this._events.setHandler(event, handler);
+  }
+
+  protected getEventHandler<K extends keyof AppBridgeEventMap>(
+    event: K,
+  ): ((params: AppBridgeEventMap[K]) => void) | undefined {
+    return this._events.getHandler(event);
+  }
+
+  addEventListener<K extends keyof AppBridgeEventMap>(
+    event: K,
+    handler: (params: AppBridgeEventMap[K]) => void,
+  ): void {
+    this._ensureEventSlot(event);
+    this._events.addEventListener(event, handler);
+  }
+
+  removeEventListener<K extends keyof AppBridgeEventMap>(
+    event: K,
+    handler: (params: AppBridgeEventMap[K]) => void,
+  ): void {
+    this._events.removeEventListener(event, handler);
+  }
+
+  private _ensureEventSlot<K extends keyof AppBridgeEventMap>(event: K): void {
+    if (this._registeredEvents.has(event)) return;
+    const schema = this.eventSchemas[event];
+    if (!schema) throw new Error(`Unknown event: ${String(event)}`);
+
+    const dispatch = (params: AppBridgeEventMap[K]) => {
+      if (event === "initialized") this._initializedReceived = true;
+      this._events.dispatch(event, params);
+    };
+
+    if (event === "loggingmessage") {
+      this.setNotificationHandler("notifications/message", (notification) => {
+        dispatch(notification.params as AppBridgeEventMap[K]);
+      });
+    } else {
+      this.setNotificationHandler(
+        schema.shape.method.value,
+        { params: schema.shape.params },
+        (params) => dispatch(params as AppBridgeEventMap[K]),
+      );
+    }
+    this._registeredEvents.add(event);
+  }
+
+  protected warnIfRequestHandlerReplaced(
+    name: string,
+    previous: unknown,
+    next: unknown,
+  ): void {
+    if (previous && next) {
+      console.warn(
+        `[MCP Apps] ${name} handler replaced. ` +
+          `Previous handler will no longer be called.`,
+      );
+    }
+  }
+
+  private ensureInnerCapabilities(capabilities: ServerCapabilities): void {
+    const current = super.getCapabilities();
+    const missing = Object.keys(capabilities).some(
+      (key) => current[key as keyof ServerCapabilities] === undefined,
+    );
+    if (missing) this.registerCapabilities(capabilities);
+  }
+
   /**
    * Create a new AppBridge instance.
    *
@@ -359,8 +455,8 @@ export class AppBridge extends ProtocolWithEvents<
    *   between the View and the server. When `null`, you must register handlers
    *   manually using the {@link oncalltool `oncalltool`}, {@link onlistresources `onlistresources`}, etc. setters.
    * @param _hostInfo - Host application identification (name and version)
-   * @param _capabilities - Features and capabilities the host supports
-   * @param options - Configuration options (inherited from Protocol)
+   * @param _hostCapabilities - Features and capabilities the host supports
+   * @param options - Configuration options (inherited from Server)
    *
    * @example With MCP client (automatic forwarding)
    * ```ts source="./app-bridge.examples.ts#AppBridge_constructor_withMcpClient"
@@ -387,31 +483,61 @@ export class AppBridge extends ProtocolWithEvents<
   constructor(
     private _client: Client | null,
     private _hostInfo: Implementation,
-    private _capabilities: McpUiHostCapabilities,
+    private _hostCapabilities: McpUiHostCapabilities,
     options?: HostOptions,
   ) {
-    super(options);
+    // TEMPORARY INNER-CHANNEL NEGOTIATION:
+    // App and AppBridge use the public v2 Client/Server roles, so the iframe
+    // channel first completes the SDK's standard legacy MCP initialization.
+    // ui/initialize remains authoritative for Apps capabilities, identity, and
+    // host context, and ui/notifications/initialized remains the View-ready gate.
+    // Keep the inner MCP era pinned to 2025-11-25. Revisit this sequence only
+    // after the MCP Apps negotiation specification is resolved:
+    // https://github.com/modelcontextprotocol/ext-apps/issues/708
+    super(_hostInfo, {
+      ...options,
+      capabilities: {},
+      supportedProtocolVersions: [INNER_MCP_PROTOCOL_VERSION],
+    });
 
-    this.addEventListener("initialized", () => {
-      this._initializedReceived = true;
+    // The base Server's standard initialized callback is MCP-ready state. The
+    // public AppBridge callback remains exclusively the Apps View-ready gate.
+    super.setNotificationHandler("notifications/initialized", () => {});
+    Object.defineProperty(this, "oninitialized", {
+      configurable: true,
+      enumerable: true,
+      get: () => this.getEventHandler("initialized"),
+      set: (callback: AppBridge["oninitialized"]) =>
+        this.setEventHandler("initialized", callback),
     });
 
+    this._ensureEventSlot("initialized");
+
     this._hostContext = options?.hostContext || {};
 
-    this.setRequestHandler(McpUiInitializeRequestSchema, (request) =>
-      this._oninitialize(request),
+    this.setRequestHandler(
+      "ui/initialize",
+      {
+        params: McpUiInitializeRequestSchema.shape.params,
+        result: McpUiInitializeResultSchema,
+      },
+      (params) => this._onAppsInitialize(params),
     );
 
-    this.setRequestHandler(PingRequestSchema, (request, extra) => {
+    this.setRequestHandler("ping", (request, extra) => {
       this.onping?.(request.params, extra);
       return {};
     });
 
     // Default handler for requestDisplayMode - returns current mode from host context.
     // Hosts can override this by setting bridge.onrequestdisplaymode = ...
-    this.replaceRequestHandler(
-      McpUiRequestDisplayModeRequestSchema,
-      (request) => {
+    this.setRequestHandler(
+      "ui/request-display-mode",
+      {
+        params: McpUiRequestDisplayModeRequestSchema.shape.params,
+        result: McpUiRequestDisplayModeResultSchema,
+      },
+      () => {
         const currentMode = this._hostContext.displayMode ?? "inline";
         return { mode: currentMode };
       },
@@ -541,8 +667,7 @@ export class AppBridge extends ProtocolWithEvents<
    * ```typescript
    * bridge.onsandboxready = async () => {
    *   const resource = await mcpClient.request(
-   *     { method: "resources/read", params: { uri: "ui://my-app" } },
-   *     ReadResourceResultSchema
+   *     { method: "resources/read", params: { uri: "ui://my-app" } }
    *   );
    *
    *   bridge.sendSandboxResourceReady({
@@ -588,18 +713,9 @@ export class AppBridge extends ProtocolWithEvents<
    * @see {@link sendToolInput `sendToolInput`} for sending tool arguments to the View
    * @deprecated Use {@link addEventListener `addEventListener("initialized", handler)`} instead — it composes with other listeners and supports cleanup via {@link removeEventListener `removeEventListener`}.
    */
-  get oninitialized():
-    | ((params: McpUiInitializedNotification["params"]) => void)
-    | undefined {
-    return this.getEventHandler("initialized");
-  }
-  set oninitialized(
-    callback:
-      | ((params: McpUiInitializedNotification["params"]) => void)
-      | undefined,
-  ) {
-    this.setEventHandler("initialized", callback);
-  }
+  override oninitialized?: (
+    params?: McpUiInitializedNotification["params"],
+  ) => void;
 
   /**
    * Register a handler for message requests from the view.
@@ -652,11 +768,15 @@ export class AppBridge extends ProtocolWithEvents<
   ) {
     this.warnIfRequestHandlerReplaced("onmessage", this._onmessage, callback);
     this._onmessage = callback;
-    this.replaceRequestHandler(
-      McpUiMessageRequestSchema,
-      async (request, extra) => {
+    this.setRequestHandler(
+      "ui/message",
+      {
+        params: McpUiMessageRequestSchema.shape.params,
+        result: McpUiMessageResultSchema,
+      },
+      async (params, extra) => {
         if (!this._onmessage) throw new Error("No onmessage handler set");
-        return this._onmessage(request.params, extra);
+        return this._onmessage(params, extra);
       },
     );
   }
@@ -721,11 +841,15 @@ export class AppBridge extends ProtocolWithEvents<
   ) {
     this.warnIfRequestHandlerReplaced("onopenlink", this._onopenlink, callback);
     this._onopenlink = callback;
-    this.replaceRequestHandler(
-      McpUiOpenLinkRequestSchema,
-      async (request, extra) => {
+    this.setRequestHandler(
+      "ui/open-link",
+      {
+        params: McpUiOpenLinkRequestSchema.shape.params,
+        result: McpUiOpenLinkResultSchema,
+      },
+      async (params, extra) => {
         if (!this._onopenlink) throw new Error("No onopenlink handler set");
-        return this._onopenlink(request.params, extra);
+        return this._onopenlink(params, extra);
       },
     );
   }
@@ -793,12 +917,16 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._ondownloadfile = callback;
-    this.replaceRequestHandler(
-      McpUiDownloadFileRequestSchema,
-      async (request, extra) => {
+    this.setRequestHandler(
+      "ui/download-file",
+      {
+        params: McpUiDownloadFileRequestSchema.shape.params,
+        result: McpUiDownloadFileResultSchema,
+      },
+      async (params, extra) => {
         if (!this._ondownloadfile)
           throw new Error("No ondownloadfile handler set");
-        return this._ondownloadfile(request.params, extra);
+        return this._ondownloadfile(params, extra);
       },
     );
   }
@@ -893,12 +1021,16 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._onrequestdisplaymode = callback;
-    this.replaceRequestHandler(
-      McpUiRequestDisplayModeRequestSchema,
-      async (request, extra) => {
+    this.setRequestHandler(
+      "ui/request-display-mode",
+      {
+        params: McpUiRequestDisplayModeRequestSchema.shape.params,
+        result: McpUiRequestDisplayModeResultSchema,
+      },
+      async (params, extra) => {
         if (!this._onrequestdisplaymode)
           throw new Error("No onrequestdisplaymode handler set");
-        return this._onrequestdisplaymode(request.params, extra);
+        return this._onrequestdisplaymode(params, extra);
       },
     );
   }
@@ -990,12 +1122,16 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._onupdatemodelcontext = callback;
-    this.replaceRequestHandler(
-      McpUiUpdateModelContextRequestSchema,
-      async (request, extra) => {
+    this.setRequestHandler(
+      "ui/update-model-context",
+      {
+        params: McpUiUpdateModelContextRequestSchema.shape.params,
+        result: EmptyResultSchema,
+      },
+      async (params, extra) => {
         if (!this._onupdatemodelcontext)
           throw new Error("No onupdatemodelcontext handler set");
-        return this._onupdatemodelcontext(request.params, extra);
+        return this._onupdatemodelcontext(params, extra);
       },
     );
   }
@@ -1017,14 +1153,13 @@ export class AppBridge extends ProtocolWithEvents<
    * bridge.oncalltool = async (params, extra) => {
    *   return mcpClient.request(
    *     { method: "tools/call", params },
-   *     CallToolResultSchema,
-   *     { signal: extra.signal },
+   *     { signal: extra.mcpReq.signal },
    *   );
    * };
    * ```
    *
-   * @see `CallToolRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `CallToolResult` from @modelcontextprotocol/sdk for the result type
+   * @see `CallToolRequest` from @modelcontextprotocol/server for the request type
+   * @see `CallToolResult` from @modelcontextprotocol/server for the result type
    */
   private _oncalltool?: (
     params: CallToolRequest["params"],
@@ -1043,13 +1178,11 @@ export class AppBridge extends ProtocolWithEvents<
   ) {
     this.warnIfRequestHandlerReplaced("oncalltool", this._oncalltool, callback);
     this._oncalltool = callback;
-    this.replaceRequestHandler(
-      CallToolRequestSchema,
-      async (request, extra) => {
-        if (!this._oncalltool) throw new Error("No oncalltool handler set");
-        return this._oncalltool(request.params, extra);
-      },
-    );
+    this.ensureInnerCapabilities({ tools: {} });
+    this.setRequestHandler("tools/call", async (request, extra) => {
+      if (!this._oncalltool) throw new Error("No oncalltool handler set");
+      return this._oncalltool(request.params, extra);
+    });
   }
 
   /**
@@ -1074,12 +1207,14 @@ export class AppBridge extends ProtocolWithEvents<
    * ```ts source="./app-bridge.examples.ts#AppBridge_oncreatesamplingmessage_forwardToLlm"
    * bridge.oncreatesamplingmessage = async (params, extra) => {
    *   // Apply rate limiting, user approval, cost controls here
-   *   return await myLlmProvider.complete(params, { signal: extra.signal });
+   *   return await myLlmProvider.complete(params, {
+   *     signal: extra.mcpReq.signal,
+   *   });
    * };
    * ```
    *
-   * @see `CreateMessageRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `CreateMessageResult` / `CreateMessageResultWithTools` from @modelcontextprotocol/sdk for result types
+   * @see `CreateMessageRequest` from @modelcontextprotocol/server for the request type
+   * @see `CreateMessageResult` / `CreateMessageResultWithTools` from @modelcontextprotocol/server for result types
    */
   set oncreatesamplingmessage(
     callback: (
@@ -1087,12 +1222,9 @@ export class AppBridge extends ProtocolWithEvents<
       extra: RequestHandlerExtra,
     ) => Promise<CreateMessageResult | CreateMessageResultWithTools>,
   ) {
-    this.setRequestHandler(
-      CreateMessageRequestSchema,
-      async (request, extra) => {
-        return callback(request.params, extra);
-      },
-    );
+    this.setRequestHandler("sampling/createMessage", async (request, extra) => {
+      return callback(request.params, extra);
+    });
   }
 
   /**
@@ -1112,7 +1244,7 @@ export class AppBridge extends ProtocolWithEvents<
    * });
    * ```
    *
-   * @see `ToolListChangedNotification` from @modelcontextprotocol/sdk for the notification type
+   * @see `ToolListChangedNotification` from @modelcontextprotocol/server for the notification type
    */
   sendToolListChanged(params: ToolListChangedNotification["params"] = {}) {
     return this.notification({
@@ -1138,14 +1270,13 @@ export class AppBridge extends ProtocolWithEvents<
    * bridge.onlistresources = async (params, extra) => {
    *   return mcpClient.request(
    *     { method: "resources/list", params },
-   *     ListResourcesResultSchema,
-   *     { signal: extra.signal },
+   *     { signal: extra.mcpReq.signal },
    *   );
    * };
    * ```
    *
-   * @see `ListResourcesRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `ListResourcesResult` from @modelcontextprotocol/sdk for the result type
+   * @see `ListResourcesRequest` from @modelcontextprotocol/server for the request type
+   * @see `ListResourcesResult` from @modelcontextprotocol/server for the result type
    */
   private _onlistresources?: (
     params: ListResourcesRequest["params"],
@@ -1168,14 +1299,12 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._onlistresources = callback;
-    this.replaceRequestHandler(
-      ListResourcesRequestSchema,
-      async (request, extra) => {
-        if (!this._onlistresources)
-          throw new Error("No onlistresources handler set");
-        return this._onlistresources(request.params, extra);
-      },
-    );
+    this.ensureInnerCapabilities({ resources: {} });
+    this.setRequestHandler("resources/list", async (request, extra) => {
+      if (!this._onlistresources)
+        throw new Error("No onlistresources handler set");
+      return this._onlistresources(request.params, extra);
+    });
   }
 
   /**
@@ -1195,14 +1324,13 @@ export class AppBridge extends ProtocolWithEvents<
    * bridge.onlistresourcetemplates = async (params, extra) => {
    *   return mcpClient.request(
    *     { method: "resources/templates/list", params },
-   *     ListResourceTemplatesResultSchema,
-   *     { signal: extra.signal }
+   *     { signal: extra.mcpReq.signal }
    *   );
    * };
    * ```
    *
-   * @see `ListResourceTemplatesRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `ListResourceTemplatesResult` from @modelcontextprotocol/sdk for the result type
+   * @see `ListResourceTemplatesRequest` from @modelcontextprotocol/server for the request type
+   * @see `ListResourceTemplatesResult` from @modelcontextprotocol/server for the result type
    */
   private _onlistresourcetemplates?: (
     params: ListResourceTemplatesRequest["params"],
@@ -1225,8 +1353,9 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._onlistresourcetemplates = callback;
-    this.replaceRequestHandler(
-      ListResourceTemplatesRequestSchema,
+    this.ensureInnerCapabilities({ resources: {} });
+    this.setRequestHandler(
+      "resources/templates/list",
       async (request, extra) => {
         if (!this._onlistresourcetemplates)
           throw new Error("No onlistresourcetemplates handler set");
@@ -1252,14 +1381,13 @@ export class AppBridge extends ProtocolWithEvents<
    * bridge.onreadresource = async (params, extra) => {
    *   return mcpClient.request(
    *     { method: "resources/read", params },
-   *     ReadResourceResultSchema,
-   *     { signal: extra.signal },
+   *     { signal: extra.mcpReq.signal },
    *   );
    * };
    * ```
    *
-   * @see `ReadResourceRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `ReadResourceResult` from @modelcontextprotocol/sdk for the result type
+   * @see `ReadResourceRequest` from @modelcontextprotocol/server for the request type
+   * @see `ReadResourceResult` from @modelcontextprotocol/server for the result type
    */
   private _onreadresource?: (
     params: ReadResourceRequest["params"],
@@ -1282,14 +1410,12 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._onreadresource = callback;
-    this.replaceRequestHandler(
-      ReadResourceRequestSchema,
-      async (request, extra) => {
-        if (!this._onreadresource)
-          throw new Error("No onreadresource handler set");
-        return this._onreadresource(request.params, extra);
-      },
-    );
+    this.ensureInnerCapabilities({ resources: {} });
+    this.setRequestHandler("resources/read", async (request, extra) => {
+      if (!this._onreadresource)
+        throw new Error("No onreadresource handler set");
+      return this._onreadresource(request.params, extra);
+    });
   }
 
   /**
@@ -1309,7 +1435,7 @@ export class AppBridge extends ProtocolWithEvents<
    * });
    * ```
    *
-   * @see `ResourceListChangedNotification` from @modelcontextprotocol/sdk for the notification type
+   * @see `ResourceListChangedNotification` from @modelcontextprotocol/server for the notification type
    */
   sendResourceListChanged(
     params: ResourceListChangedNotification["params"] = {},
@@ -1337,14 +1463,13 @@ export class AppBridge extends ProtocolWithEvents<
    * bridge.onlistprompts = async (params, extra) => {
    *   return mcpClient.request(
    *     { method: "prompts/list", params },
-   *     ListPromptsResultSchema,
-   *     { signal: extra.signal },
+   *     { signal: extra.mcpReq.signal },
    *   );
    * };
    * ```
    *
-   * @see `ListPromptsRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `ListPromptsResult` from @modelcontextprotocol/sdk for the result type
+   * @see `ListPromptsRequest` from @modelcontextprotocol/server for the request type
+   * @see `ListPromptsResult` from @modelcontextprotocol/server for the result type
    */
   private _onlistprompts?: (
     params: ListPromptsRequest["params"],
@@ -1367,14 +1492,11 @@ export class AppBridge extends ProtocolWithEvents<
       callback,
     );
     this._onlistprompts = callback;
-    this.replaceRequestHandler(
-      ListPromptsRequestSchema,
-      async (request, extra) => {
-        if (!this._onlistprompts)
-          throw new Error("No onlistprompts handler set");
-        return this._onlistprompts(request.params, extra);
-      },
-    );
+    this.ensureInnerCapabilities({ prompts: {} });
+    this.setRequestHandler("prompts/list", async (request, extra) => {
+      if (!this._onlistprompts) throw new Error("No onlistprompts handler set");
+      return this._onlistprompts(request.params, extra);
+    });
   }
 
   /**
@@ -1394,7 +1516,7 @@ export class AppBridge extends ProtocolWithEvents<
    * });
    * ```
    *
-   * @see `PromptListChangedNotification` from @modelcontextprotocol/sdk for the notification type
+   * @see `PromptListChangedNotification` from @modelcontextprotocol/server for the notification type
    */
   sendPromptListChanged(params: PromptListChangedNotification["params"] = {}) {
     return this.notification({
@@ -1403,46 +1525,6 @@ export class AppBridge extends ProtocolWithEvents<
     });
   }
 
-  /**
-   * Verify that the guest supports the capability required for the given request method.
-   * @internal
-   */
-  assertCapabilityForMethod(method: AppRequest["method"]): void {
-    // TODO
-  }
-
-  /**
-   * Verify that a request handler is registered and supported for the given method.
-   * @internal
-   */
-  assertRequestHandlerCapability(method: AppRequest["method"]): void {
-    // TODO
-  }
-
-  /**
-   * Verify that the host supports the capability required for the given notification method.
-   * @internal
-   */
-  assertNotificationCapability(method: AppNotification["method"]): void {
-    // TODO
-  }
-
-  /**
-   * Verify that task creation is supported for the given request method.
-   * @internal
-   */
-  protected assertTaskCapability(_method: string): void {
-    throw new Error("Tasks are not supported in MCP Apps");
-  }
-
-  /**
-   * Verify that task handler is supported for the given method.
-   * @internal
-   */
-  protected assertTaskHandlerCapability(_method: string): void {
-    throw new Error("Task handlers are not supported in MCP Apps");
-  }
-
   /**
    * Get the host capabilities passed to the constructor.
    *
@@ -1450,18 +1532,18 @@ export class AppBridge extends ProtocolWithEvents<
    *
    * @see {@link McpUiHostCapabilities `McpUiHostCapabilities`} for the capabilities structure
    */
-  getCapabilities(): McpUiHostCapabilities {
-    return this._capabilities;
+  getHostCapabilities(): McpUiHostCapabilities {
+    return this._hostCapabilities;
   }
 
   /**
    * Handle the ui/initialize request from the guest.
    * @internal
    */
-  private async _oninitialize(
-    request: McpUiInitializeRequest,
+  private async _onAppsInitialize(
+    params: McpUiInitializeRequest["params"],
   ): Promise<McpUiInitializeResult> {
-    const requestedVersion = request.params.protocolVersion;
+    const requestedVersion = params.protocolVersion;
 
     if (this._appInfo !== undefined) {
       console.warn(
@@ -1472,8 +1554,8 @@ export class AppBridge extends ProtocolWithEvents<
       );
     }
 
-    this._appCapabilities = request.params.appCapabilities;
-    this._appInfo = request.params.appInfo;
+    this._appCapabilities = params.appCapabilities;
+    this._appInfo = params.appInfo;
 
     const protocolVersion = SUPPORTED_PROTOCOL_VERSIONS.includes(
       requestedVersion,
@@ -1483,7 +1565,7 @@ export class AppBridge extends ProtocolWithEvents<
 
     return {
       protocolVersion,
-      hostCapabilities: this.getCapabilities(),
+      hostCapabilities: this.getHostCapabilities(),
       hostInfo: this._hostInfo,
       hostContext: this._hostContext,
     };
@@ -1636,10 +1718,10 @@ export class AppBridge extends ProtocolWithEvents<
    *
    * @example
    * ```ts source="./app-bridge.examples.ts#AppBridge_sendToolResult_afterExecution"
-   * const result = await mcpClient.request(
-   *   { method: "tools/call", params: { name: "get_weather", arguments: args } },
-   *   CallToolResultSchema,
-   * );
+   * const result = await mcpClient.request({
+   *   method: "tools/call",
+   *   params: { name: "get_weather", arguments: args },
+   * });
    * bridge.sendToolResult(result);
    * ```
    *
@@ -1765,11 +1847,7 @@ export class AppBridge extends ProtocolWithEvents<
    * @returns Promise resolving to the tool call result
    */
   callTool(params: CallToolRequest["params"], options?: RequestOptions) {
-    return this.request(
-      { method: "tools/call", params },
-      CallToolResultSchema,
-      options,
-    );
+    return this.request({ method: "tools/call", params }, options);
   }
 
   /**
@@ -1782,11 +1860,7 @@ export class AppBridge extends ProtocolWithEvents<
    * @returns Promise resolving to the list of tools
    */
   listTools(params: ListToolsRequest["params"], options?: RequestOptions) {
-    return this.request(
-      { method: "tools/list", params },
-      ListToolsResultSchema,
-      options,
-    );
+    return this.request({ method: "tools/list", params }, options);
   }
 
   /**
@@ -1857,18 +1931,18 @@ export class AppBridge extends ProtocolWithEvents<
       if (!serverCapabilities) {
         throw new Error("Client server capabilities not available");
       }
+      this.registerCapabilities(proxiedInnerCapabilities(serverCapabilities));
 
       if (serverCapabilities.tools) {
         this.oncalltool = async (params, extra) => {
           return this._client!.request(
             { method: "tools/call", params },
-            CallToolResultSchema,
-            { signal: extra.signal },
+            { signal: extra.mcpReq.signal },
           );
         };
         if (serverCapabilities.tools.listChanged) {
           this._client.setNotificationHandler(
-            ToolListChangedNotificationSchema,
+            "notifications/tools/list_changed",
             (n) => this.sendToolListChanged(n.params),
           );
         }
@@ -1877,27 +1951,24 @@ export class AppBridge extends ProtocolWithEvents<
         this.onlistresources = async (params, extra) => {
           return this._client!.request(
             { method: "resources/list", params },
-            ListResourcesResultSchema,
-            { signal: extra.signal },
+            { signal: extra.mcpReq.signal },
           );
         };
         this.onlistresourcetemplates = async (params, extra) => {
           return this._client!.request(
             { method: "resources/templates/list", params },
-            ListResourceTemplatesResultSchema,
-            { signal: extra.signal },
+            { signal: extra.mcpReq.signal },
           );
         };
         this.onreadresource = async (params, extra) => {
           return this._client!.request(
             { method: "resources/read", params },
-            ReadResourceResultSchema,
-            { signal: extra.signal },
+            { signal: extra.mcpReq.signal },
           );
         };
         if (serverCapabilities.resources.listChanged) {
           this._client.setNotificationHandler(
-            ResourceListChangedNotificationSchema,
+            "notifications/resources/list_changed",
             (n) => this.sendResourceListChanged(n.params),
           );
         }
@@ -1906,22 +1977,20 @@ export class AppBridge extends ProtocolWithEvents<
         this.onlistprompts = async (params, extra) => {
           return this._client!.request(
             { method: "prompts/list", params },
-            ListPromptsResultSchema,
-            { signal: extra.signal },
+            { signal: extra.mcpReq.signal },
           );
         };
         if (serverCapabilities.prompts.listChanged) {
           this._client.setNotificationHandler(
-            PromptListChangedNotificationSchema,
+            "notifications/prompts/list_changed",
             (n) => this.sendPromptListChanged(n.params),
           );
         }
       }
     }
 
-    // MCP-UI specific handlers are registered by the host component
-    // after the proxy is created. The standard MCP initialization
-    // (via oninitialized callback set in constructor) handles the ready signal.
+    // The standard MCP handshake only establishes the temporary inner Server
+    // role. ui/notifications/initialized remains the public View-ready signal.
 
     return super.connect(transport);
   }
diff --git a/src/app.examples.ts b/src/app.examples.ts
index 81bdd4440..7d475efa0 100644
--- a/src/app.examples.ts
+++ b/src/app.examples.ts
@@ -7,11 +7,8 @@
  * @module
  */
 
-import type { Tool } from "@modelcontextprotocol/sdk/types.js";
-import type {
-  McpServer,
-  ToolCallback,
-} from "@modelcontextprotocol/sdk/server/mcp.js";
+import type { SamplingMessage, Tool } from "@modelcontextprotocol/client";
+import type { McpServer, ToolCallback } from "@modelcontextprotocol/server";
 import {
   App,
   PostMessageTransport,
@@ -369,7 +366,7 @@ async function App_createSamplingMessage_simple(app: App) {
  */
 async function App_createSamplingMessage_withTools(
   app: App,
-  messages: import("@modelcontextprotocol/sdk/types.js").SamplingMessage[],
+  messages: SamplingMessage[],
 ) {
   //#region App_createSamplingMessage_withTools
   if (!app.getHostCapabilities()?.sampling?.tools) return;
diff --git a/src/app.test.ts b/src/app.test.ts
new file mode 100644
index 000000000..dcf2d5287
--- /dev/null
+++ b/src/app.test.ts
@@ -0,0 +1,300 @@
+import { afterEach, describe, expect, it } from "bun:test";
+import {
+  InMemoryTransport,
+  Server,
+  type JSONRPCMessage,
+} from "@modelcontextprotocol/server";
+import { z } from "zod/v4";
+
+import { App } from "./app";
+import {
+  LATEST_PROTOCOL_VERSION,
+  McpUiInitializeRequestSchema,
+  McpUiInitializeResultSchema,
+  McpUiInitializedNotificationSchema,
+} from "./types";
+
+const INNER_MCP_PROTOCOL_VERSION = "2025-11-25";
+
+type ConnectedPair = {
+  app: App;
+  server: Server;
+  sentByApp: JSONRPCMessage[];
+  appsInitialized: Promise<void>;
+};
+
+async function connectPair(
+  app = new App(
+    { name: "view-app", version: "1.0.0" },
+    { tools: { listChanged: true } },
+    { autoResize: false },
+  ),
+): Promise<ConnectedPair> {
+  const server = new Server(
+    { name: "inner-mcp-server", version: "0.0.0" },
+    {
+      capabilities: { resources: {}, tools: {} },
+      supportedProtocolVersions: [INNER_MCP_PROTOCOL_VERSION],
+    },
+  );
+  const [appTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+  const sentByApp: JSONRPCMessage[] = [];
+  const send = appTransport.send.bind(appTransport);
+  appTransport.send = async (message, options) => {
+    sentByApp.push(message);
+    await send(message, options);
+  };
+
+  let resolveAppsInitialized!: () => void;
+  const appsInitialized = new Promise<void>((resolve) => {
+    resolveAppsInitialized = resolve;
+  });
+
+  server.setRequestHandler(
+    "ui/initialize",
+    {
+      params: McpUiInitializeRequestSchema.shape.params,
+      result: McpUiInitializeResultSchema,
+    },
+    (params) => {
+      expect(params.protocolVersion).toBe(LATEST_PROTOCOL_VERSION);
+      return {
+        protocolVersion: LATEST_PROTOCOL_VERSION,
+        hostCapabilities: { openLinks: {} },
+        hostInfo: { name: "apps-host", version: "2.0.0" },
+        hostContext: { theme: "dark" as const, locale: "en-US" },
+      };
+    },
+  );
+  server.setNotificationHandler(
+    "ui/notifications/initialized",
+    { params: McpUiInitializedNotificationSchema.shape.params },
+    () => resolveAppsInitialized(),
+  );
+  server.setRequestHandler("tools/call", (request) => ({
+    content: [{ type: "text", text: `called ${request.params.name}` }],
+  }));
+  server.setRequestHandler("resources/read", (request) => ({
+    contents: [{ uri: request.params.uri, text: "resource body" }],
+  }));
+  server.setRequestHandler("resources/list", () => ({
+    resources: [{ uri: "test://resource", name: "Test resource" }],
+  }));
+  server.setRequestHandler("sampling/createMessage", () => ({
+    model: "test-model",
+    role: "assistant",
+    content: { type: "text", text: "sampled" },
+  }));
+
+  await server.connect(serverTransport);
+  await app.connect(appTransport);
+  await appsInitialized;
+
+  return { app, server, sentByApp, appsInitialized };
+}
+
+const connected: Array<Pick<ConnectedPair, "app" | "server">> = [];
+
+afterEach(async () => {
+  await Promise.all(
+    connected
+      .splice(0)
+      .flatMap(({ app, server }) => [app.close(), server.close()]),
+  );
+});
+
+describe("App base MCP SDK v2 Client migration", () => {
+  it("completes the legacy MCP handshake before the authoritative Apps handshake", async () => {
+    const pair = await connectPair();
+    connected.push(pair);
+
+    const lifecycleMethods = pair.sentByApp
+      .filter(
+        (message): message is JSONRPCMessage & { method: string } =>
+          "method" in message,
+      )
+      .map((message) => message.method)
+      .filter((method) =>
+        [
+          "initialize",
+          "notifications/initialized",
+          "ui/initialize",
+          "ui/notifications/initialized",
+        ].includes(method),
+      );
+
+    expect(lifecycleMethods).toEqual([
+      "initialize",
+      "notifications/initialized",
+      "ui/initialize",
+      "ui/notifications/initialized",
+    ]);
+    expect(pair.app.getNegotiatedProtocolVersion()).toBe(
+      INNER_MCP_PROTOCOL_VERSION,
+    );
+  });
+
+  it("uses ui/initialize as the authority for Apps host state", async () => {
+    const pair = await connectPair();
+    connected.push(pair);
+
+    expect(pair.app.getServerVersion()).toEqual({
+      name: "inner-mcp-server",
+      version: "0.0.0",
+    });
+    expect(pair.app.getHostVersion()).toEqual({
+      name: "apps-host",
+      version: "2.0.0",
+    });
+    expect(pair.app.getHostCapabilities()).toEqual({ openLinks: {} });
+    expect(pair.app.getHostContext()).toEqual({
+      theme: "dark",
+      locale: "en-US",
+    });
+  });
+
+  it("preserves registered App tools with the base MCP SDK v2 Client handler context", async () => {
+    const pair = await connectPair();
+    connected.push(pair);
+    let receivedSignal: AbortSignal | undefined;
+
+    pair.app.registerTool(
+      "greet",
+      { description: "Greets a person" },
+      async (extra) => {
+        receivedSignal = extra.mcpReq.signal;
+        return { content: [{ type: "text", text: "hello" }] };
+      },
+    );
+
+    const listed = await pair.server.request({
+      method: "tools/list",
+      params: {},
+    });
+    const result = await pair.server.request({
+      method: "tools/call",
+      params: { name: "greet", arguments: {} },
+    });
+
+    expect(listed.tools.map((tool) => tool.name)).toEqual(["greet"]);
+    expect(result.content).toEqual([{ type: "text", text: "hello" }]);
+    expect(receivedSignal).toBeInstanceOf(AbortSignal);
+  });
+
+  it("uses base MCP SDK v2 method-keyed sends for standard MCP requests", async () => {
+    const pair = await connectPair();
+    connected.push(pair);
+
+    const toolResult = await pair.app.callServerTool({
+      name: "refresh",
+      arguments: {},
+    });
+    const resource = await pair.app.readServerResource({
+      uri: "test://resource",
+    });
+    const resources = await pair.app.listServerResources();
+    const sample = await pair.app.createSamplingMessage({
+      messages: [{ role: "user", content: { type: "text", text: "hello" } }],
+      maxTokens: 20,
+    });
+
+    expect(toolResult.content).toEqual([
+      { type: "text", text: "called refresh" },
+    ]);
+    expect(resource.contents[0]).toEqual({
+      uri: "test://resource",
+      text: "resource body",
+    });
+    expect(resources.resources.map(({ uri }) => uri)).toEqual([
+      "test://resource",
+    ]);
+    expect(sample.content).toEqual({ type: "text", text: "sampled" });
+  });
+
+  it("preserves reconnect behavior after close", async () => {
+    const first = await connectPair();
+    await first.app.close();
+    await first.server.close();
+
+    const second = await connectPair(first.app);
+    connected.push(second);
+
+    expect(second.app.getNegotiatedProtocolVersion()).toBe(
+      INNER_MCP_PROTOCOL_VERSION,
+    );
+    expect(second.app.getHostVersion()).toEqual({
+      name: "apps-host",
+      version: "2.0.0",
+    });
+  });
+
+  it("preserves auto-resize setup after Apps initialization", async () => {
+    const app = new App(
+      { name: "view-app", version: "1.0.0" },
+      {},
+      { autoResize: true },
+    );
+    let setupCalls = 0;
+    app.setupSizeChangedNotifications = () => {
+      setupCalls += 1;
+      return () => {};
+    };
+
+    const pair = await connectPair(app);
+    connected.push(pair);
+
+    expect(setupCalls).toBe(1);
+  });
+
+  it("preserves strict late-handler timing errors", async () => {
+    const app = new App(
+      { name: "view-app", version: "1.0.0" },
+      {},
+      { autoResize: false, strict: true },
+    );
+    const pair = await connectPair(app);
+    connected.push(pair);
+
+    expect(() => {
+      app.ontoolinput = () => {};
+    }).toThrow(/handler registered after connect/);
+  });
+
+  it("uses base MCP SDK replacement semantics for request handlers", async () => {
+    const pair = await connectPair();
+    connected.push(pair);
+    let handledBy = 0;
+
+    pair.app.setRequestHandler("ping", () => {
+      handledBy = 1;
+      return {};
+    });
+    pair.app.setRequestHandler("ping", () => {
+      handledBy = 2;
+      return {};
+    });
+
+    await pair.server.request({ method: "ping", params: {} });
+    expect(handledBy).toBe(2);
+  });
+
+  it("uses base MCP SDK replacement semantics for non-event notifications", async () => {
+    const pair = await connectPair();
+    connected.push(pair);
+    const calls: number[] = [];
+    const params = z.object({});
+
+    pair.app.setNotificationHandler("test/notification", { params }, () => {
+      calls.push(1);
+    });
+    pair.app.setNotificationHandler("test/notification", { params }, () => {
+      calls.push(2);
+    });
+    await pair.server.notification({
+      method: "test/notification",
+      params: {},
+    });
+
+    expect(calls).toEqual([2]);
+  });
+});
diff --git a/src/app.ts b/src/app.ts
index adfad5c77..7e752cec3 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -1,39 +1,29 @@
 import {
+  Client,
+  type ClientContext,
+  type ClientOptions,
   type RequestOptions,
-  mergeCapabilities,
-  ProtocolOptions,
-} from "@modelcontextprotocol/sdk/shared/protocol.js";
-
-import {
-  CallToolRequest,
-  CallToolRequestSchema,
-  CallToolResult,
-  CallToolResultSchema,
-  CreateMessageRequest,
-  CreateMessageResult,
-  CreateMessageResultSchema,
-  CreateMessageResultWithTools,
-  CreateMessageResultWithToolsSchema,
-  EmptyResultSchema,
-  Implementation,
-  ListResourcesRequest,
-  ListResourcesResult,
-  ListResourcesResultSchema,
-  ListToolsRequest,
-  ListToolsRequestSchema,
-  ListToolsResult,
-  LoggingMessageNotification,
-  PingRequestSchema,
-  ReadResourceRequest,
-  ReadResourceResult,
-  ReadResourceResultSchema,
-  Tool,
-  ToolAnnotations,
-  ToolListChangedNotification,
-} from "@modelcontextprotocol/sdk/types.js";
-import { AppNotification, AppRequest, AppResult } from "./types";
-import { ProtocolWithEvents } from "./events";
-export { ProtocolWithEvents };
+  type CallToolRequest,
+  type CallToolResult,
+  type CreateMessageRequest,
+  type CreateMessageResult,
+  type CreateMessageResultWithTools,
+  type Implementation,
+  type ListResourcesRequest,
+  type ListResourcesResult,
+  type ListToolsRequest,
+  type ListToolsResult,
+  type LoggingMessageNotification,
+  type ReadResourceRequest,
+  type ReadResourceResult,
+  type Tool,
+  type ToolAnnotations,
+  type ToolListChangedNotification,
+  type Transport,
+} from "@modelcontextprotocol/client";
+import { EmptyResultSchema } from "@modelcontextprotocol/core";
+import { EventDispatcher } from "./events";
+export { EventDispatcher } from "./events";
 import { PostMessageTransport } from "./message-transport";
 import {
   LATEST_PROTOCOL_VERSION,
@@ -55,6 +45,7 @@ import {
   McpUiResourceTeardownRequest,
   McpUiResourceTeardownRequestSchema,
   McpUiResourceTeardownResult,
+  McpUiResourceTeardownResultSchema,
   McpUiRequestTeardownNotification,
   McpUiSizeChangedNotification,
   McpUiToolCancelledNotification,
@@ -68,13 +59,36 @@ import {
   McpUiRequestDisplayModeRequest,
   McpUiRequestDisplayModeResultSchema,
 } from "./types";
-import { Transport } from "@modelcontextprotocol/sdk/shared/transport.js";
 import {
   StandardSchemaV1,
   standardSchemaToJsonSchema,
   validateStandardSchema,
 } from "./standard-schema";
-import { z } from "zod/v4";
+import { z, type ZodLiteral, type ZodObject, type ZodType } from "zod/v4";
+
+type MethodSchema = ZodObject<{
+  method: ZodLiteral<string>;
+  params: ZodType;
+}>;
+
+const INNER_MCP_PROTOCOL_VERSION = "2025-11-25";
+
+function mergeAppCapabilities(
+  base: McpUiAppCapabilities,
+  additional: McpUiAppCapabilities,
+): McpUiAppCapabilities {
+  const result = { ...base, ...additional };
+  if (additional.experimental !== undefined) {
+    result.experimental = {
+      ...base.experimental,
+      ...additional.experimental,
+    };
+  }
+  if (additional.tools !== undefined) {
+    result.tools = { ...base.tools, ...additional.tools };
+  }
+  return result;
+}
 
 export type {
   StandardSchemaV1,
@@ -160,11 +174,14 @@ export const RESOURCE_MIME_TYPE = "text/html;profile=mcp-app";
 /**
  * Options for configuring {@link App `App`} behavior.
  *
- * Extends `ProtocolOptions` from the MCP SDK with `App`-specific configuration.
+ * Extends `ClientOptions` from the base MCP SDK with `App`-specific configuration.
  *
- * @see `ProtocolOptions` from @modelcontextprotocol/sdk for inherited options
+ * @see `ClientOptions` from @modelcontextprotocol/client for inherited options
  */
-export type AppOptions = ProtocolOptions & {
+export type AppOptions = Omit<
+  ClientOptions,
+  "capabilities" | "supportedProtocolVersions" | "versionNegotiation"
+> & {
   /**
    * Automatically report size changes to the host using `ResizeObserver`.
    *
@@ -204,9 +221,7 @@ export type AppOptions = ProtocolOptions & {
   allowUnsafeEval?: boolean;
 };
 
-type RequestHandlerExtra = Parameters<
-  Parameters<App["setRequestHandler"]>[1]
->[1];
+type RequestHandlerExtra = ClientContext;
 
 /**
  * Result of an app-registered tool callback. When `Out` is provided,
@@ -228,7 +243,7 @@ export type AppToolResult<
  * validated/parsed input; when `In` is `undefined`, the callback receives only
  * `extra`. When `Out` is provided, the return's `structuredContent` is typed.
  *
- * Mirrors `ToolCallback` from `@modelcontextprotocol/sdk/server/mcp.js` but is
+ * Mirrors `ToolCallback` from `@modelcontextprotocol/server` but is
  * parameterized over {@link StandardSchemaV1} instead of zod, so any
  * Standard-Schema-compatible library (Zod, ArkType, Valibot, …) can be used.
  */
@@ -246,7 +261,7 @@ export type AppToolCallback<
 
 /**
  * Handle returned by {@link App.registerTool}. Mirrors `RegisteredTool` from
- * `@modelcontextprotocol/sdk/server/mcp.js` but stores
+ * `@modelcontextprotocol/server` but stores
  * {@link StandardSchemaV1} schemas.
  */
 export type RegisteredAppTool = {
@@ -271,9 +286,9 @@ export type RegisteredAppTool = {
 /**
  * Maps DOM-style event names to their notification `params` types.
  *
- * Used by {@link App `App`} (which extends {@link ProtocolWithEvents `ProtocolWithEvents`})
- * to provide type-safe `addEventListener` / `removeEventListener` and
- * singular `on*` handler support.
+ * Used by {@link App `App`} and its composed {@link EventDispatcher} to
+ * provide type-safe `addEventListener` / `removeEventListener` and singular
+ * `on*` handler support.
  */
 export type AppEventMap = {
   toolinput: McpUiToolInputNotification["params"];
@@ -287,9 +302,8 @@ export type AppEventMap = {
  * Main class for MCP Apps to communicate with their host.
  *
  * The `App` class provides a framework-agnostic way to build interactive MCP Apps
- * that run inside host applications. It extends the MCP SDK's `Protocol` class and
- * handles the connection lifecycle, initialization handshake, and bidirectional
- * communication with the host.
+ * that run inside host applications. It extends the base MCP SDK's public
+ * `Client` class and adds the Apps handshake, lifecycle, and high-level APIs.
  *
  * ## Architecture
  *
@@ -304,16 +318,14 @@ export type AppEventMap = {
  * 3. **Interactive**: Send requests, receive notifications, call tools
  * 4. **Teardown**: Host sends teardown request before unmounting
  *
- * ## Inherited Methods
+ * ## Protocol and event methods
  *
- * As a subclass of {@link ProtocolWithEvents `ProtocolWithEvents`}, `App` inherits:
+ * As a subclass of the base MCP SDK's `Client`, `App` provides:
  * - `setRequestHandler()` - Register handlers for requests from host
  * - `setNotificationHandler()` - Register handlers for notifications from host
  * - `addEventListener()` - Append a listener for a notification event (multi-listener)
  * - `removeEventListener()` - Remove a previously added listener
  *
- * @see {@link ProtocolWithEvents `ProtocolWithEvents`} for the DOM-model event system
- *
  * ## Notification Setters (DOM-model `on*` handlers)
  *
  * For common notifications, the `App` class provides getter/setter properties
@@ -342,17 +354,14 @@ export type AppEventMap = {
  * await app.connect();
  * ```
  */
-export class App extends ProtocolWithEvents<
-  AppRequest,
-  AppNotification,
-  AppResult,
-  AppEventMap
-> {
+export class App extends Client {
   private _hostCapabilities?: McpUiHostCapabilities;
   private _hostInfo?: Implementation;
   private _hostContext?: McpUiHostContext;
   private _registeredTools: { [name: string]: RegisteredAppTool } = {};
   private _initializedSent = false;
+  private readonly _registeredEvents = new Set<keyof AppEventMap>();
+  private readonly _events = new EventDispatcher<AppEventMap>();
 
   /**
    * Warn if a host-bound method is called before {@link connect `connect`} has
@@ -378,7 +387,9 @@ export class App extends ProtocolWithEvents<
     console.warn(`${msg}. This will throw in a future release.`);
   }
 
-  protected readonly eventSchemas = {
+  private readonly eventSchemas: {
+    [K in keyof AppEventMap]: MethodSchema;
+  } = {
     toolinput: McpUiToolInputNotificationSchema,
     toolinputpartial: McpUiToolInputPartialNotificationSchema,
     toolresult: McpUiToolResultNotificationSchema,
@@ -427,28 +438,65 @@ export class App extends ProtocolWithEvents<
     console.warn(msg);
   }
 
-  protected override setEventHandler<K extends keyof AppEventMap>(
+  protected setEventHandler<K extends keyof AppEventMap>(
     event: K,
     handler: ((params: AppEventMap[K]) => void) | undefined,
   ): void {
     if (handler) this._assertHandlerTiming(event);
-    super.setEventHandler(event, handler);
+    this._ensureEventSlot(event);
+    this._events.setHandler(event, handler);
   }
 
-  override addEventListener<K extends keyof AppEventMap>(
+  addEventListener<K extends keyof AppEventMap>(
     event: K,
     handler: (params: AppEventMap[K]) => void,
   ): void {
     this._assertHandlerTiming(event);
-    super.addEventListener(event, handler);
+    this._ensureEventSlot(event);
+    this._events.addEventListener(event, handler);
   }
 
-  protected override onEventDispatch<K extends keyof AppEventMap>(
+  removeEventListener<K extends keyof AppEventMap>(
     event: K,
-    params: AppEventMap[K],
+    handler: (params: AppEventMap[K]) => void,
   ): void {
-    if (event === "hostcontextchanged") {
-      this._hostContext = { ...this._hostContext, ...params };
+    this._events.removeEventListener(event, handler);
+  }
+
+  private _ensureEventSlot<K extends keyof AppEventMap>(event: K): void {
+    if (this._registeredEvents.has(event)) return;
+    const schema = this.eventSchemas[event];
+    if (!schema) throw new Error(`Unknown event: ${String(event)}`);
+    this.setNotificationHandler(
+      schema.shape.method.value,
+      { params: schema.shape.params },
+      (params) => {
+        const eventParams = params as AppEventMap[K];
+        if (event === "hostcontextchanged") {
+          this._hostContext = { ...this._hostContext, ...eventParams };
+        }
+        this._events.dispatch(event, eventParams);
+      },
+    );
+    this._registeredEvents.add(event);
+  }
+
+  protected getEventHandler<K extends keyof AppEventMap>(
+    event: K,
+  ): ((params: AppEventMap[K]) => void) | undefined {
+    return this._events.getHandler(event);
+  }
+
+  protected warnIfRequestHandlerReplaced(
+    name: string,
+    previous: unknown,
+    next: unknown,
+  ): void {
+    if (previous && next) {
+      console.warn(
+        `[MCP Apps] ${name} handler replaced. ` +
+          `Previous handler will no longer be called.`,
+      );
     }
   }
 
@@ -456,7 +504,7 @@ export class App extends ProtocolWithEvents<
    * Create a new MCP App instance.
    *
    * @param _appInfo - App identification (name and version)
-   * @param _capabilities - Features and capabilities this app provides
+   * @param _appCapabilities - Features and capabilities this app provides
    * @param options - Configuration options including `autoResize` behavior
    *
    * @example
@@ -470,33 +518,48 @@ export class App extends ProtocolWithEvents<
    */
   constructor(
     private _appInfo: Implementation,
-    private _capabilities: McpUiAppCapabilities = {},
+    private _appCapabilities: McpUiAppCapabilities = {},
     private options: AppOptions = { autoResize: true },
   ) {
-    super(options);
+    // TEMPORARY INNER-CHANNEL NEGOTIATION:
+    // App and AppBridge use the public v2 Client/Server roles, so the iframe
+    // channel first completes the SDK's standard legacy MCP initialization.
+    // ui/initialize remains authoritative for Apps capabilities, identity, and
+    // host context, and ui/notifications/initialized remains the View-ready gate.
+    // Keep the inner MCP era pinned to 2025-11-25. Revisit this sequence only
+    // after the MCP Apps negotiation specification is resolved:
+    // https://github.com/modelcontextprotocol/ext-apps/issues/708
+    super(_appInfo, {
+      ...options,
+      capabilities: {},
+      versionNegotiation: { mode: "legacy" },
+      supportedProtocolVersions: [INNER_MCP_PROTOCOL_VERSION],
+    });
 
     if (!options.allowUnsafeEval) {
       z.config({ jitless: true });
     }
 
-    this.setRequestHandler(PingRequestSchema, (request) => {
+    this.setRequestHandler("ping", (request) => {
       console.log("Received ping:", request.params);
       return {};
     });
 
-    // Eagerly register the hostcontextchanged event slot so that
-    // onEventDispatch (which merges into _hostContext) fires even if the
-    // user never assigns onhostcontextchanged or calls addEventListener.
+    // Eagerly register hostcontextchanged so the owner-side context merge runs
+    // even if the user never assigns a handler or adds a listener.
     this.setEventHandler("hostcontextchanged", undefined);
   }
 
-  private registerCapabilities(capabilities: McpUiAppCapabilities): void {
+  private registerAppCapabilities(capabilities: McpUiAppCapabilities): void {
     if (this.transport) {
       throw new Error(
         "Cannot register capabilities after transport is established",
       );
     }
-    this._capabilities = mergeCapabilities(this._capabilities, capabilities);
+    this._appCapabilities = mergeAppCapabilities(
+      this._appCapabilities,
+      capabilities,
+    );
   }
 
   registerTool<
@@ -519,7 +582,7 @@ export class App extends ProtocolWithEvents<
     }
     const app = this;
     const notify = () => {
-      if (app._initializedSent && app._capabilities.tools?.listChanged) {
+      if (app._initializedSent && app._appCapabilities.tools?.listChanged) {
         void app.sendToolListChanged();
       }
     };
@@ -591,8 +654,8 @@ export class App extends ProtocolWithEvents<
     // to declare { tools: {} } in the constructor just to use registerTool.
     // Only do this pre-connect; post-connect the capability was already
     // advertised (or wasn't) and can't change.
-    if (!this._capabilities.tools && !this.transport) {
-      this.registerCapabilities({ tools: { listChanged: true } });
+    if (!this._appCapabilities.tools && !this.transport) {
+      this.registerAppCapabilities({ tools: { listChanged: true } });
     }
 
     this.ensureToolHandlersInitialized();
@@ -924,9 +987,9 @@ export class App extends ProtocolWithEvents<
    * without replacing.
    *
    * Notification params are automatically merged into the internal host context
-   * via {@link onEventDispatch `onEventDispatch`} before any handler or listener
-   * fires. This means {@link getHostContext `getHostContext`} will return the
-   * updated values even before your callback runs.
+   * before any handler or listener fires. This means
+   * {@link getHostContext `getHostContext`} will return the updated values even
+   * before your callback runs.
    *
    * Register handlers before calling {@link connect `connect`} to avoid missing notifications.
    *
@@ -1004,11 +1067,15 @@ export class App extends ProtocolWithEvents<
   ) {
     this.warnIfRequestHandlerReplaced("onteardown", this._onteardown, callback);
     this._onteardown = callback;
-    this.replaceRequestHandler(
-      McpUiResourceTeardownRequestSchema,
-      (request, extra) => {
+    this.setRequestHandler(
+      "ui/resource-teardown",
+      {
+        params: McpUiResourceTeardownRequestSchema.shape.params,
+        result: McpUiResourceTeardownResultSchema,
+      },
+      (params, extra) => {
         if (!this._onteardown) throw new Error("No onteardown handler set");
-        return this._onteardown(request.params, extra);
+        return this._onteardown(params, extra);
       },
     );
   }
@@ -1058,7 +1125,7 @@ export class App extends ProtocolWithEvents<
   ) {
     this.warnIfRequestHandlerReplaced("oncalltool", this._oncalltool, callback);
     this._oncalltool = callback;
-    this.replaceRequestHandler(CallToolRequestSchema, (request, extra) => {
+    this.setRequestHandler("tools/call", (request, extra) => {
       if (!this._oncalltool) throw new Error("No oncalltool handler set");
       return this._oncalltool(request.params, extra);
     });
@@ -1129,7 +1196,7 @@ export class App extends ProtocolWithEvents<
       callback,
     );
     this._onlisttools = callback;
-    this.replaceRequestHandler(ListToolsRequestSchema, (request, extra) => {
+    this.setRequestHandler("tools/list", (request, extra) => {
       if (!this._onlisttools) throw new Error("No onlisttools handler set");
       return this._onlisttools(request.params, extra);
     });
@@ -1139,7 +1206,7 @@ export class App extends ProtocolWithEvents<
    * Verify that the host supports the capability required for the given request method.
    * @internal
    */
-  assertCapabilityForMethod(method: AppRequest["method"]): void {
+  protected override assertCapabilityForMethod(method: string): void {
     switch (method) {
       case "sampling/createMessage":
         if (!this._hostCapabilities?.sampling) {
@@ -1155,11 +1222,11 @@ export class App extends ProtocolWithEvents<
    * Verify that the app declared the capability required for the given request method.
    * @internal
    */
-  assertRequestHandlerCapability(method: AppRequest["method"]): void {
+  protected override assertRequestHandlerCapability(method: string): void {
     switch (method) {
       case "tools/call":
       case "tools/list":
-        if (!this._capabilities.tools) {
+        if (!this._appCapabilities.tools) {
           throw new Error(
             `Client does not support tool capability (required for ${method})`,
           );
@@ -1177,26 +1244,10 @@ export class App extends ProtocolWithEvents<
    * Verify that the app supports the capability required for the given notification method.
    * @internal
    */
-  assertNotificationCapability(_method: AppNotification["method"]): void {
+  protected override assertNotificationCapability(_method: string): void {
     // TODO
   }
 
-  /**
-   * Verify that task creation is supported for the given request method.
-   * @internal
-   */
-  protected assertTaskCapability(_method: string): void {
-    throw new Error("Tasks are not supported in MCP Apps");
-  }
-
-  /**
-   * Verify that task handler is supported for the given method.
-   * @internal
-   */
-  protected assertTaskHandlerCapability(_method: string): void {
-    throw new Error("Task handlers are not supported in MCP Apps");
-  }
-
   /**
    * Call a tool on the originating MCP server (proxied through the host).
    *
@@ -1245,7 +1296,6 @@ export class App extends ProtocolWithEvents<
     }
     return await this.request(
       { method: "tools/call", params },
-      CallToolResultSchema,
       {
         // Hosts may interpose long-running or user-interactive steps before the
         // tool result arrives. Opting in here lets a host heartbeat keep the
@@ -1302,11 +1352,7 @@ export class App extends ProtocolWithEvents<
     options?: RequestOptions,
   ): Promise<ReadResourceResult> {
     this._assertInitialized("readServerResource");
-    return await this.request(
-      { method: "resources/read", params },
-      ReadResourceResultSchema,
-      options,
-    );
+    return await this.request({ method: "resources/read", params }, options);
   }
 
   /**
@@ -1350,11 +1396,7 @@ export class App extends ProtocolWithEvents<
     options?: RequestOptions,
   ): Promise<ListResourcesResult> {
     this._assertInitialized("listServerResources");
-    return await this.request(
-      { method: "resources/list", params },
-      ListResourcesResultSchema,
-      options,
-    );
+    return await this.request({ method: "resources/list", params }, options);
   }
 
   /**
@@ -1415,8 +1457,8 @@ export class App extends ProtocolWithEvents<
    * }
    * ```
    *
-   * @see `CreateMessageRequest` from @modelcontextprotocol/sdk for the request type
-   * @see `CreateMessageResult` / `CreateMessageResultWithTools` from @modelcontextprotocol/sdk for result types
+   * @see `CreateMessageRequest` from @modelcontextprotocol/client for the request type
+   * @see `CreateMessageResult` / `CreateMessageResultWithTools` from @modelcontextprotocol/client for result types
    */
   async createSamplingMessage(
     params: CreateMessageRequest["params"] & { tools?: undefined },
@@ -1431,12 +1473,8 @@ export class App extends ProtocolWithEvents<
     options?: RequestOptions,
   ): Promise<CreateMessageResult | CreateMessageResultWithTools> {
     this._assertInitialized("createSamplingMessage");
-    const resultSchema = params.tools
-      ? CreateMessageResultWithToolsSchema
-      : CreateMessageResultSchema;
     return await this.request(
       { method: "sampling/createMessage", params },
-      resultSchema,
       options,
     );
   }
@@ -1953,14 +1991,23 @@ export class App extends ProtocolWithEvents<
       );
     }
     this._initializedSent = false;
-    await super.connect(transport);
 
+    // TEMPORARY INNER-CHANNEL NEGOTIATION:
+    // App and AppBridge use the public v2 Client/Server roles, so the iframe
+    // channel first completes the SDK's standard legacy MCP initialization.
+    // ui/initialize remains authoritative for Apps capabilities, identity, and
+    // host context, and ui/notifications/initialized remains the View-ready gate.
+    // Keep the inner MCP era pinned to 2025-11-25. Revisit this sequence only
+    // after the MCP Apps negotiation specification is resolved:
+    // https://github.com/modelcontextprotocol/ext-apps/issues/708
     try {
+      await super.connect(transport);
+
       const result = await this.request(
         <McpUiInitializeRequest>{
           method: "ui/initialize",
           params: {
-            appCapabilities: this._capabilities,
+            appCapabilities: this._appCapabilities,
             appInfo: this._appInfo,
             protocolVersion: LATEST_PROTOCOL_VERSION,
           },
diff --git a/src/events.test.ts b/src/events.test.ts
new file mode 100644
index 000000000..7fd87087f
--- /dev/null
+++ b/src/events.test.ts
@@ -0,0 +1,82 @@
+import { describe, expect, it, spyOn } from "bun:test";
+
+import { EventDispatcher } from "./events";
+
+type TestEventMap = {
+  change: { value: number };
+};
+
+describe("EventDispatcher", () => {
+  it("replaces the singular handler", () => {
+    const dispatcher = new EventDispatcher<TestEventMap>();
+    const calls: string[] = [];
+    const first = () => calls.push("first");
+    const second = () => calls.push("second");
+    const warn = spyOn(console, "warn").mockImplementation(() => {});
+
+    try {
+      dispatcher.setHandler("change", first);
+      dispatcher.setHandler("change", second);
+
+      expect(dispatcher.getHandler("change")).toBe(second);
+      dispatcher.dispatch("change", { value: 1 });
+      expect(calls).toEqual(["second"]);
+    } finally {
+      warn.mockRestore();
+    }
+  });
+
+  it("dispatches the singular handler before listeners in insertion order", () => {
+    const dispatcher = new EventDispatcher<TestEventMap>();
+    const calls: string[] = [];
+
+    dispatcher.setHandler("change", () => calls.push("handler"));
+    dispatcher.addEventListener("change", () => calls.push("listener-1"));
+    dispatcher.addEventListener("change", () => calls.push("listener-2"));
+
+    dispatcher.dispatch("change", { value: 1 });
+
+    expect(calls).toEqual(["handler", "listener-1", "listener-2"]);
+  });
+
+  it("uses a listener snapshot when a listener is removed during dispatch", () => {
+    const dispatcher = new EventDispatcher<TestEventMap>();
+    const calls: string[] = [];
+    const second = () => calls.push("second");
+    const first = () => {
+      calls.push("first");
+      dispatcher.removeEventListener("change", second);
+    };
+
+    dispatcher.addEventListener("change", first);
+    dispatcher.addEventListener("change", second);
+
+    dispatcher.dispatch("change", { value: 1 });
+    dispatcher.dispatch("change", { value: 2 });
+
+    expect(calls).toEqual(["first", "second", "first"]);
+  });
+
+  it("warns only when one singular handler replaces another", () => {
+    const dispatcher = new EventDispatcher<TestEventMap>();
+    const warn = spyOn(console, "warn").mockImplementation(() => {});
+    const first = () => {};
+    const second = () => {};
+
+    try {
+      dispatcher.setHandler("change", first);
+      dispatcher.setHandler("change", undefined);
+      dispatcher.setHandler("change", first);
+      expect(warn).not.toHaveBeenCalled();
+
+      dispatcher.setHandler("change", second);
+
+      expect(warn).toHaveBeenCalledTimes(1);
+      expect(String(warn.mock.calls[0]?.[0])).toContain(
+        "onchange handler replaced",
+      );
+    } finally {
+      warn.mockRestore();
+    }
+  });
+});
diff --git a/src/events.ts b/src/events.ts
index 4d17ca4f2..aff144605 100644
--- a/src/events.ts
+++ b/src/events.ts
@@ -1,17 +1,6 @@
-import { Protocol } from "@modelcontextprotocol/sdk/shared/protocol.js";
-import {
-  Request,
-  Notification,
-  Result,
-} from "@modelcontextprotocol/sdk/types.js";
-import { ZodLiteral, ZodObject } from "zod/v4";
-
-type MethodSchema = ZodObject<{ method: ZodLiteral<string> }>;
-
 /**
- * Per-event state: a singular `on*` handler (replace semantics) plus a
- * listener array (`addEventListener` semantics), mirroring the DOM model
- * where `el.onclick` and `el.addEventListener("click", …)` coexist.
+ * Per-event state: a singular `on*` handler (replace semantics) plus an
+ * ordered listener array (`addEventListener` semantics).
  */
 interface EventSlot<T = unknown> {
   onHandler?: ((params: T) => void) | undefined;
@@ -19,118 +8,19 @@ interface EventSlot<T = unknown> {
 }
 
 /**
- * Intermediate base class that adds DOM-style event support on top of the
- * MCP SDK's `Protocol`.
- *
- * The base `Protocol` class stores one handler per method:
- * `setRequestHandler()` and `setNotificationHandler()` replace any existing
- * handler for the same method silently. This class introduces a two-channel
- * event model inspired by the DOM:
- *
- * ### Singular `on*` handler (like `el.onclick`)
- *
- * Subclasses expose `get`/`set` pairs that delegate to
- * {@link setEventHandler `setEventHandler`} /
- * {@link getEventHandler `getEventHandler`}. Assigning replaces the previous
- * handler; assigning `undefined` clears it. `addEventListener` listeners are
- * unaffected.
- *
- * ### Multi-listener (`addEventListener` / `removeEventListener`)
- *
- * Append to a per-event listener array. Listeners fire in insertion order
- * after the singular `on*` handler.
- *
- * ### Dispatch order
- *
- * When a notification arrives for a mapped event:
- * 1. {@link onEventDispatch `onEventDispatch`} (subclass side-effects)
- * 2. The singular `on*` handler (if set)
- * 3. All `addEventListener` listeners in insertion order
+ * Protocol-independent DOM-style event fan-out.
  *
- * ### Double-set protection
+ * Owners perform event-specific state updates before calling
+ * {@link dispatch}. Dispatch then invokes the singular handler followed by a
+ * snapshot of listeners in insertion order.
  *
- * Direct calls to {@link setRequestHandler `setRequestHandler`} /
- * {@link setNotificationHandler `setNotificationHandler`} throw if a handler
- * for the same method has already been registered (through any path), so
- * accidental overwrites surface as errors instead of silent bugs.
- *
- * @typeParam EventMap - Maps event names to the listener's `params` type.
+ * @typeParam EventMap - Maps event names to their listener parameter types.
  */
-export abstract class ProtocolWithEvents<
-  SendRequestT extends Request,
-  SendNotificationT extends Notification,
-  SendResultT extends Result,
-  EventMap extends Record<string, unknown>,
-> extends Protocol<SendRequestT, SendNotificationT, SendResultT> {
-  private _registeredMethods = new Set<string>();
-  private _eventSlots = new Map<keyof EventMap, EventSlot>();
-
-  /**
-   * Event name → notification schema. Subclasses populate this so that
-   * the event system can lazily register a dispatcher with the correct
-   * schema on first use.
-   */
-  protected abstract readonly eventSchemas: {
-    [K in keyof EventMap]: MethodSchema;
-  };
-
-  /**
-   * Called once per incoming notification, before any handlers or listeners
-   * fire. Subclasses may override to perform side effects such as merging
-   * notification params into cached state.
-   */
-  protected onEventDispatch<K extends keyof EventMap>(
-    _event: K,
-    _params: EventMap[K],
-  ): void {}
-
-  // ── Event system (DOM model) ────────────────────────────────────────
-
-  /**
-   * Lazily create the event slot and register a single dispatcher with the
-   * base `Protocol`. The dispatcher fans out to the `on*` handler and all
-   * `addEventListener` listeners.
-   */
-  private _ensureEventSlot<K extends keyof EventMap>(
-    event: K,
-  ): EventSlot<EventMap[K]> {
-    let slot = this._eventSlots.get(event) as
-      | EventSlot<EventMap[K]>
-      | undefined;
-    if (!slot) {
-      const schema = this.eventSchemas[event];
-      if (!schema) {
-        throw new Error(`Unknown event: ${String(event)}`);
-      }
-      slot = { listeners: [] };
-      this._eventSlots.set(event, slot as EventSlot);
-
-      // Claim this method so direct setNotificationHandler calls throw.
-      const method = schema.shape.method.value;
-      this._registeredMethods.add(method);
+export class EventDispatcher<EventMap extends Record<string, unknown>> {
+  private readonly _eventSlots = new Map<keyof EventMap, EventSlot>();
 
-      const s = slot; // stable reference for the closure
-      super.setNotificationHandler(schema, (n) => {
-        const params = (n as { params: EventMap[K] }).params;
-        this.onEventDispatch(event, params);
-        // 1. Singular on* handler
-        s.onHandler?.(params);
-        // 2. addEventListener listeners — snapshot to tolerate removal during
-        //    dispatch (e.g., a listener that calls removeEventListener on itself)
-        for (const l of [...s.listeners]) l(params);
-      });
-    }
-    return slot;
-  }
-
-  /**
-   * Set or clear the singular `on*` handler for an event.
-   *
-   * Replace semantics — like the DOM's `el.onclick = fn`. Assigning
-   * `undefined` clears the handler without affecting `addEventListener`
-   * listeners.
-   */
-  protected setEventHandler<K extends keyof EventMap>(
+  /** Set, replace, or clear the singular handler for an event. */
+  setHandler<K extends keyof EventMap>(
     event: K,
     handler: ((params: EventMap[K]) => void) | undefined,
   ): void {
@@ -144,31 +34,15 @@ export abstract class ProtocolWithEvents<
     slot.onHandler = handler;
   }
 
-  /**
-   * Get the singular `on*` handler for an event, or `undefined` if none is
-   * set. `addEventListener` listeners are not reflected here.
-   */
-  protected getEventHandler<K extends keyof EventMap>(
+  /** Get the singular handler for an event, if one is set. */
+  getHandler<K extends keyof EventMap>(
     event: K,
   ): ((params: EventMap[K]) => void) | undefined {
     return (this._eventSlots.get(event) as EventSlot<EventMap[K]> | undefined)
       ?.onHandler;
   }
 
-  /**
-   * Add a listener for a notification event.
-   *
-   * Unlike the singular `on*` handler, calling this multiple times appends
-   * listeners rather than replacing them. All registered listeners fire in
-   * insertion order after the `on*` handler when the notification arrives.
-   *
-   * Registration is lazy: the first call (for a given event, from either
-   * this method or the `on*` setter) registers a dispatcher with the base
-   * `Protocol`.
-   *
-   * @param event - Event name (a key of the `EventMap` type parameter).
-   * @param handler - Listener invoked with the notification `params`.
-   */
+  /** Add a listener. Listeners run in insertion order after the handler. */
   addEventListener<K extends keyof EventMap>(
     event: K,
     handler: (params: EventMap[K]) => void,
@@ -176,11 +50,7 @@ export abstract class ProtocolWithEvents<
     this._ensureEventSlot(event).listeners.push(handler);
   }
 
-  /**
-   * Remove a previously registered event listener. The dispatcher stays
-   * registered even if the listener array becomes empty; future
-   * notifications simply have no listeners to call.
-   */
+  /** Remove the first matching listener, if present. */
   removeEventListener<K extends keyof EventMap>(
     event: K,
     handler: (params: EventMap[K]) => void,
@@ -193,87 +63,29 @@ export abstract class ProtocolWithEvents<
     if (idx !== -1) slot.listeners.splice(idx, 1);
   }
 
-  // ── Handler registration with double-set protection ─────────────────
-
-  // The two overrides below are arrow-function class fields rather than
-  // prototype methods so that Protocol's constructor — which registers its
-  // own ping/cancelled/progress handlers via `this.setRequestHandler`
-  // before our fields initialize — hits the base implementation and skips
-  // tracking. Converting these to proper methods would crash with
-  // `_registeredMethods` undefined during super().
-
-  /**
-   * Registers a request handler. Throws if a handler for the same method
-   * has already been registered — use the `on*` setter (replace semantics)
-   * or `addEventListener` (multi-listener) for notification events.
-   *
-   * @throws {Error} if a handler for this method is already registered.
-   */
-  override setRequestHandler: Protocol<
-    SendRequestT,
-    SendNotificationT,
-    SendResultT
-  >["setRequestHandler"] = (schema, handler) => {
-    this._assertMethodNotRegistered(schema, "setRequestHandler");
-    super.setRequestHandler(schema, handler);
-  };
-
-  /**
-   * Registers a notification handler. Throws if a handler for the same
-   * method has already been registered — use the `on*` setter (replace
-   * semantics) or `addEventListener` (multi-listener) for mapped events.
-   *
-   * @throws {Error} if a handler for this method is already registered.
-   */
-  override setNotificationHandler: Protocol<
-    SendRequestT,
-    SendNotificationT,
-    SendResultT
-  >["setNotificationHandler"] = (schema, handler) => {
-    this._assertMethodNotRegistered(schema, "setNotificationHandler");
-    super.setNotificationHandler(schema, handler);
-  };
-
   /**
-   * Warn if a request handler `on*` setter is replacing a previously-set
-   * handler. Call from each request setter before updating the backing field.
+   * Dispatch an event to its singular handler and a listener snapshot.
+   * Listener mutations during dispatch take effect on the next dispatch.
    */
-  protected warnIfRequestHandlerReplaced(
-    name: string,
-    previous: unknown,
-    next: unknown,
-  ): void {
-    if (previous && next) {
-      console.warn(
-        `[MCP Apps] ${name} handler replaced. ` +
-          `Previous handler will no longer be called.`,
-      );
-    }
+  dispatch<K extends keyof EventMap>(event: K, params: EventMap[K]): void {
+    const slot = this._eventSlots.get(event) as
+      | EventSlot<EventMap[K]>
+      | undefined;
+    if (!slot) return;
+    slot.onHandler?.(params);
+    for (const l of [...slot.listeners]) l(params);
   }
 
-  /**
-   * Replace a request handler, bypassing double-set protection. Used by
-   * `on*` request-handler setters that need replace semantics.
-   */
-  protected replaceRequestHandler: Protocol<
-    SendRequestT,
-    SendNotificationT,
-    SendResultT
-  >["setRequestHandler"] = (schema, handler) => {
-    const method = (schema as MethodSchema).shape.method.value;
-    this._registeredMethods.add(method);
-    super.setRequestHandler(schema, handler);
-  };
-
-  private _assertMethodNotRegistered(schema: unknown, via: string): void {
-    const method = (schema as MethodSchema).shape.method.value;
-    if (this._registeredMethods.has(method)) {
-      throw new Error(
-        `Handler for "${method}" already registered (via ${via}). ` +
-          `Use addEventListener() to attach multiple listeners, ` +
-          `or the on* setter for replace semantics.`,
-      );
+  private _ensureEventSlot<K extends keyof EventMap>(
+    event: K,
+  ): EventSlot<EventMap[K]> {
+    let slot = this._eventSlots.get(event) as
+      | EventSlot<EventMap[K]>
+      | undefined;
+    if (!slot) {
+      slot = { listeners: [] };
+      this._eventSlots.set(event, slot as EventSlot);
     }
-    this._registeredMethods.add(method);
+    return slot;
   }
 }
diff --git a/src/generated/schema.json b/src/generated/schema.json
index 80b4ac60d..5f2124a95 100644
--- a/src/generated/schema.json
+++ b/src/generated/schema.json
@@ -596,7 +596,9 @@
                           "propertyNames": {
                             "type": "string"
                           },
-                          "additionalProperties": {}
+                          "additionalProperties": {
+                            "$ref": "#/$defs/__schema0"
+                          }
                         },
                         "required": {
                           "type": "array",
@@ -611,25 +613,10 @@
                     "outputSchema": {
                       "type": "object",
                       "properties": {
-                        "type": {
-                          "type": "string",
-                          "const": "object"
-                        },
-                        "properties": {
-                          "type": "object",
-                          "propertyNames": {
-                            "type": "string"
-                          },
-                          "additionalProperties": {}
-                        },
-                        "required": {
-                          "type": "array",
-                          "items": {
-                            "type": "string"
-                          }
+                        "$schema": {
+                          "type": "string"
                         }
                       },
-                      "required": ["type"],
                       "additionalProperties": {}
                     },
                     "annotations": {
@@ -1286,7 +1273,40 @@
         }
       },
       "required": ["method", "params"],
-      "additionalProperties": false
+      "additionalProperties": false,
+      "$defs": {
+        "__schema0": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "number"
+            },
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "null"
+            },
+            {
+              "type": "object",
+              "propertyNames": {
+                "type": "string"
+              },
+              "additionalProperties": {
+                "$ref": "#/$defs/__schema0"
+              }
+            },
+            {
+              "type": "array",
+              "items": {
+                "$ref": "#/$defs/__schema0"
+              }
+            }
+          ]
+        }
+      }
     },
     "McpUiHostContext": {
       "$schema": "https://json-schema.org/draft/2020-12/schema",
@@ -1359,7 +1379,9 @@
                       "propertyNames": {
                         "type": "string"
                       },
-                      "additionalProperties": {}
+                      "additionalProperties": {
+                        "$ref": "#/$defs/__schema0"
+                      }
                     },
                     "required": {
                       "type": "array",
@@ -1374,25 +1396,10 @@
                 "outputSchema": {
                   "type": "object",
                   "properties": {
-                    "type": {
-                      "type": "string",
-                      "const": "object"
-                    },
-                    "properties": {
-                      "type": "object",
-                      "propertyNames": {
-                        "type": "string"
-                      },
-                      "additionalProperties": {}
-                    },
-                    "required": {
-                      "type": "array",
-                      "items": {
-                        "type": "string"
-                      }
+                    "$schema": {
+                      "type": "string"
                     }
                   },
-                  "required": ["type"],
                   "additionalProperties": {}
                 },
                 "annotations": {
@@ -2044,7 +2051,40 @@
           "additionalProperties": false
         }
       },
-      "additionalProperties": {}
+      "additionalProperties": {},
+      "$defs": {
+        "__schema0": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "number"
+            },
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "null"
+            },
+            {
+              "type": "object",
+              "propertyNames": {
+                "type": "string"
+              },
+              "additionalProperties": {
+                "$ref": "#/$defs/__schema0"
+              }
+            },
+            {
+              "type": "array",
+              "items": {
+                "$ref": "#/$defs/__schema0"
+              }
+            }
+          ]
+        }
+      }
     },
     "McpUiHostCss": {
       "$schema": "https://json-schema.org/draft/2020-12/schema",
@@ -2942,7 +2982,9 @@
                           "propertyNames": {
                             "type": "string"
                           },
-                          "additionalProperties": {}
+                          "additionalProperties": {
+                            "$ref": "#/$defs/__schema0"
+                          }
                         },
                         "required": {
                           "type": "array",
@@ -2957,25 +2999,10 @@
                     "outputSchema": {
                       "type": "object",
                       "properties": {
-                        "type": {
-                          "type": "string",
-                          "const": "object"
-                        },
-                        "properties": {
-                          "type": "object",
-                          "propertyNames": {
-                            "type": "string"
-                          },
-                          "additionalProperties": {}
-                        },
-                        "required": {
-                          "type": "array",
-                          "items": {
-                            "type": "string"
-                          }
+                        "$schema": {
+                          "type": "string"
                         }
                       },
-                      "required": ["type"],
                       "additionalProperties": {}
                     },
                     "annotations": {
@@ -3637,7 +3664,40 @@
         "hostCapabilities",
         "hostContext"
       ],
-      "additionalProperties": {}
+      "additionalProperties": {},
+      "$defs": {
+        "__schema0": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "number"
+            },
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "null"
+            },
+            {
+              "type": "object",
+              "propertyNames": {
+                "type": "string"
+              },
+              "additionalProperties": {
+                "$ref": "#/$defs/__schema0"
+              }
+            },
+            {
+              "type": "array",
+              "items": {
+                "$ref": "#/$defs/__schema0"
+              }
+            }
+          ]
+        }
+      }
     },
     "McpUiInitializedNotification": {
       "$schema": "https://json-schema.org/draft/2020-12/schema",
@@ -5669,13 +5729,7 @@
                 ]
               }
             },
-            "structuredContent": {
-              "type": "object",
-              "propertyNames": {
-                "type": "string"
-              },
-              "additionalProperties": {}
-            },
+            "structuredContent": {},
             "isError": {
               "type": "boolean"
             }
diff --git a/src/generated/schema.ts b/src/generated/schema.ts
index 43687374e..341c7b488 100644
--- a/src/generated/schema.ts
+++ b/src/generated/schema.ts
@@ -10,7 +10,7 @@ import {
   RequestIdSchema,
   ResourceLinkSchema,
   ToolSchema,
-} from "@modelcontextprotocol/sdk/types.js";
+} from "@modelcontextprotocol/core";
 
 /**
  * @description Color theme preference for the host environment.
diff --git a/src/message-transport.test.ts b/src/message-transport.test.ts
index d5f509204..2a115f3f9 100644
--- a/src/message-transport.test.ts
+++ b/src/message-transport.test.ts
@@ -1,5 +1,5 @@
 import { describe, it, expect, beforeEach, afterEach, mock } from "bun:test";
-import type { JSONRPCMessage } from "@modelcontextprotocol/sdk/types.js";
+import type { JSONRPCMessage } from "@modelcontextprotocol/client";
 
 import { PostMessageTransport } from "./message-transport";
 
diff --git a/src/message-transport.ts b/src/message-transport.ts
index 9d195435a..94835401f 100644
--- a/src/message-transport.ts
+++ b/src/message-transport.ts
@@ -1,12 +1,10 @@
-import {
+import { JSONRPCMessageSchema } from "@modelcontextprotocol/core";
+import type {
   JSONRPCMessage,
-  JSONRPCMessageSchema,
   MessageExtraInfo,
-} from "@modelcontextprotocol/sdk/types.js";
-import {
   Transport,
   TransportSendOptions,
-} from "@modelcontextprotocol/sdk/shared/transport.js";
+} from "@modelcontextprotocol/client";
 import { TOOL_INPUT_PARTIAL_METHOD } from "./spec.types";
 
 /**
diff --git a/src/react/useApp.tsx b/src/react/useApp.tsx
index 61892464a..0e64a74d6 100644
--- a/src/react/useApp.tsx
+++ b/src/react/useApp.tsx
@@ -1,6 +1,5 @@
 import { useEffect, useState } from "react";
-import { Implementation } from "@modelcontextprotocol/sdk/types.js";
-import { Client } from "@modelcontextprotocol/sdk/client";
+import type { Implementation } from "@modelcontextprotocol/client";
 import {
   App,
   AppOptions,
diff --git a/src/server/index.examples.ts b/src/server/index.examples.ts
index d583ae85c..9ceebcebb 100644
--- a/src/server/index.examples.ts
+++ b/src/server/index.examples.ts
@@ -9,17 +9,14 @@
 
 import * as crypto from "node:crypto";
 import * as fs from "node:fs/promises";
-import type {
-  McpServer,
-  ToolCallback,
-  ReadResourceCallback,
-} from "@modelcontextprotocol/sdk/server/mcp.js";
+import type { McpServer, ToolCallback } from "@modelcontextprotocol/server";
 import { z } from "zod";
 import {
   registerAppTool,
   registerAppResource,
   getUiCapability,
   RESOURCE_MIME_TYPE,
+  type ReadResourceCallback,
 } from "./index.js";
 
 // Stubs for external functions used in examples
@@ -74,7 +71,7 @@ function registerAppTool_basicUsage(server: McpServer) {
     {
       title: "Get Weather",
       description: "Get current weather for a location",
-      inputSchema: { location: z.string() },
+      inputSchema: z.object({ location: z.string() }),
       _meta: {
         ui: { resourceUri: "ui://weather/view.html" },
       },
@@ -122,7 +119,7 @@ function registerAppTool_appOnlyVisibility(server: McpServer) {
     "update-quantity",
     {
       description: "Update item quantity in cart",
-      inputSchema: { itemId: z.string(), quantity: z.number() },
+      inputSchema: z.object({ itemId: z.string(), quantity: z.number() }),
       _meta: {
         ui: {
           resourceUri: "ui://shop/cart.html",
diff --git a/src/server/index.test.ts b/src/server/index.test.ts
index 1853cc05a..5de341f9e 100644
--- a/src/server/index.test.ts
+++ b/src/server/index.test.ts
@@ -7,7 +7,7 @@ import {
   getUiCapability,
   EXTENSION_ID,
 } from "./index";
-import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import type { McpServer } from "@modelcontextprotocol/server";
 
 describe("registerAppTool", () => {
   it("should pass through config to server.registerTool", () => {
diff --git a/src/server/index.ts b/src/server/index.ts
index c90514acd..61e743831 100644
--- a/src/server/index.ts
+++ b/src/server/index.ts
@@ -40,24 +40,17 @@ import {
   McpUiClientCapabilities,
 } from "../app.js";
 import type {
-  BaseToolCallback,
+  ClientCapabilities,
   McpServer,
+  ReadResourceResult,
   RegisteredTool,
   ResourceMetadata,
+  StandardSchemaWithJSON,
+  ToolAnnotations,
   ToolCallback,
   ReadResourceCallback as _ReadResourceCallback,
   RegisteredResource,
-} from "@modelcontextprotocol/sdk/server/mcp.js";
-import type {
-  AnySchema,
-  ZodRawShapeCompat,
-} from "@modelcontextprotocol/sdk/server/zod-compat.js";
-import type { StandardSchemaWithJSON } from "../standard-schema";
-import type {
-  ClientCapabilities,
-  ReadResourceResult,
-  ToolAnnotations,
-} from "@modelcontextprotocol/sdk/types.js";
+} from "@modelcontextprotocol/server";
 
 // Re-exports for convenience
 export { RESOURCE_URI_META_KEY, RESOURCE_MIME_TYPE };
@@ -70,8 +63,8 @@ export type { ResourceMetadata, ToolCallback };
 export interface ToolConfig {
   title?: string;
   description?: string;
-  inputSchema?: ZodRawShapeCompat | StandardSchemaWithJSON;
-  outputSchema?: ZodRawShapeCompat | StandardSchemaWithJSON;
+  inputSchema?: StandardSchemaWithJSON;
+  outputSchema?: StandardSchemaWithJSON;
   annotations?: ToolAnnotations;
   _meta?: Record<string, unknown>;
 }
@@ -157,7 +150,7 @@ export interface McpUiAppResourceConfig extends ResourceMetadata {
  *   {
  *     title: "Get Weather",
  *     description: "Get current weather for a location",
- *     inputSchema: { location: z.string() },
+ *     inputSchema: z.object({ location: z.string() }),
  *     _meta: {
  *       ui: { resourceUri: "ui://weather/view.html" },
  *     },
@@ -197,7 +190,7 @@ export interface McpUiAppResourceConfig extends ResourceMetadata {
  *   "update-quantity",
  *   {
  *     description: "Update item quantity in cart",
- *     inputSchema: { itemId: z.string(), quantity: z.number() },
+ *     inputSchema: z.object({ itemId: z.string(), quantity: z.number() }),
  *     _meta: {
  *       ui: {
  *         resourceUri: "ui://shop/cart.html",
@@ -215,9 +208,8 @@ export interface McpUiAppResourceConfig extends ResourceMetadata {
  * @see {@link registerAppResource `registerAppResource`} to register the HTML resource referenced by the tool
  */
 export function registerAppTool<
-  OutputArgs extends ZodRawShapeCompat | StandardSchemaWithJSON,
-  InputArgs extends undefined | ZodRawShapeCompat | StandardSchemaWithJSON =
-    undefined,
+  OutputArgs extends StandardSchemaWithJSON,
+  InputArgs extends StandardSchemaWithJSON | undefined = undefined,
 >(
   server: Pick<McpServer, "registerTool">,
   name: string,
@@ -225,15 +217,7 @@ export function registerAppTool<
     inputSchema?: InputArgs;
     outputSchema?: OutputArgs;
   },
-  // The widened constraint signals the v2 API shape, but NOTE: McpServer in
-  // sdk@1.x still calls zod internals at runtime, so non-zod schemas will fail
-  // here until we depend on sdk v2. Zod (which all current callers use) is
-  // unaffected. The cast below bridges the 1.x type signature.
-  cb: ToolCallback<
-    InputArgs extends undefined | ZodRawShapeCompat | AnySchema
-      ? InputArgs
-      : AnySchema
-  >,
+  cb: ToolCallback<InputArgs>,
 ): RegisteredTool {
   // Normalize metadata for backward compatibility:
   // - If _meta.ui.resourceUri is set, also set the legacy flat key
@@ -251,14 +235,7 @@ export function registerAppTool<
     normalizedMeta = { ...meta, ui: { ...uiMeta, resourceUri: legacyUri } };
   }
 
-  // Cast bridges the widened StandardSchemaWithJSON constraint to the
-  // sdk@1.x zod-typed signature. Drops once we depend on sdk v2.
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  return server.registerTool(
-    name,
-    { ...config, _meta: normalizedMeta } as any,
-    cb as any,
-  );
+  return server.registerTool(name, { ...config, _meta: normalizedMeta }, cb);
 }
 
 export type McpUiReadResourceResult = ReadResourceResult & {
@@ -418,10 +395,6 @@ export const EXTENSION_ID = "io.modelcontextprotocol/ui";
  * This helper retrieves the capability object from the `extensions` field
  * where MCP Apps advertises its support.
  *
- * Note: The `clientCapabilities` parameter extends the SDK's `ClientCapabilities`
- * type with an `extensions` field (pending SEP-1724). Once `extensions` is added
- * to the SDK, this can use `ClientCapabilities` directly.
- *
  * @param clientCapabilities - The client capabilities from the initialize response
  * @returns The MCP Apps capability settings, or `undefined` if not supported
  *
@@ -456,10 +429,7 @@ export const EXTENSION_ID = "io.modelcontextprotocol/ui";
  * ```
  */
 export function getUiCapability(
-  clientCapabilities:
-    | (ClientCapabilities & { extensions?: Record<string, unknown> })
-    | null
-    | undefined,
+  clientCapabilities: ClientCapabilities | null | undefined,
 ): McpUiClientCapabilities | undefined {
   if (!clientCapabilities) {
     return undefined;
diff --git a/src/spec.types.ts b/src/spec.types.ts
index 7a8b33761..8b03de94f 100644
--- a/src/spec.types.ts
+++ b/src/spec.types.ts
@@ -18,7 +18,7 @@ import type {
   RequestId,
   ResourceLink,
   Tool,
-} from "@modelcontextprotocol/sdk/types.js";
+} from "@modelcontextprotocol/client";
 
 /**
  * Current protocol version supported by this SDK.
@@ -163,8 +163,8 @@ export interface McpUiOpenLinkResult {
   /** @description True if the host failed to open the URL (e.g., due to security policy). */
   isError?: boolean;
   /**
-   * Index signature required for MCP SDK `Protocol` class compatibility.
-   * Note: The generated schema uses passthrough() to allow additional properties.
+   * Additional result properties are preserved for protocol extensibility.
+   * The generated schema uses passthrough() to allow them.
    */
   [key: string]: unknown;
 }
@@ -195,8 +195,8 @@ export interface McpUiDownloadFileResult {
   /** @description True if the download failed (e.g., user cancelled or host denied). */
   isError?: boolean;
   /**
-   * Index signature required for MCP SDK `Protocol` class compatibility.
-   * Note: The generated schema uses passthrough() to allow additional properties.
+   * Additional result properties are preserved for protocol extensibility.
+   * The generated schema uses passthrough() to allow them.
    */
   [key: string]: unknown;
 }
@@ -223,8 +223,8 @@ export interface McpUiMessageResult {
   /** @description True if the host rejected or failed to deliver the message. */
   isError?: boolean;
   /**
-   * Index signature required for MCP SDK `Protocol` class compatibility.
-   * Note: The generated schema uses passthrough() to allow additional properties.
+   * Additional result properties are preserved for protocol extensibility.
+   * The generated schema uses passthrough() to allow them.
    */
   [key: string]: unknown;
 }
@@ -454,7 +454,7 @@ export interface McpUiResourceTeardownRequest {
  */
 export interface McpUiResourceTeardownResult {
   /**
-   * Index signature required for MCP SDK `Protocol` class compatibility.
+   * Additional result properties are preserved for protocol extensibility.
    */
   [key: string]: unknown;
 }
@@ -577,8 +577,8 @@ export interface McpUiInitializeResult {
   /** @description Rich context about the host environment. */
   hostContext: McpUiHostContext;
   /**
-   * Index signature required for MCP SDK `Protocol` class compatibility.
-   * Note: The generated schema uses passthrough() to allow additional properties.
+   * Additional result properties are preserved for protocol extensibility.
+   * The generated schema uses passthrough() to allow them.
    */
   [key: string]: unknown;
 }
@@ -752,7 +752,7 @@ export interface McpUiRequestDisplayModeResult {
   /** @description The display mode that was actually set. May differ from requested if not supported. */
   mode: McpUiDisplayMode;
   /**
-   * Index signature required for MCP SDK `Protocol` class compatibility.
+   * Additional result properties are preserved for protocol extensibility.
    * Note: The generated schema uses passthrough() to allow additional properties.
    */
   [key: string]: unknown;
diff --git a/src/types.ts b/src/types.ts
index 7fc6b7188..655812bd3 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -69,33 +69,6 @@ export {
   type McpUiClientCapabilities,
 } from "./spec.types.js";
 
-// Import types needed for protocol type unions (not re-exported, just used internally)
-import type {
-  McpUiInitializeRequest,
-  McpUiOpenLinkRequest,
-  McpUiDownloadFileRequest,
-  McpUiMessageRequest,
-  McpUiUpdateModelContextRequest,
-  McpUiResourceTeardownRequest,
-  McpUiRequestDisplayModeRequest,
-  McpUiHostContextChangedNotification,
-  McpUiToolInputNotification,
-  McpUiToolInputPartialNotification,
-  McpUiToolResultNotification,
-  McpUiToolCancelledNotification,
-  McpUiSandboxResourceReadyNotification,
-  McpUiInitializedNotification,
-  McpUiSizeChangedNotification,
-  McpUiSandboxProxyReadyNotification,
-  McpUiRequestTeardownNotification,
-  McpUiInitializeResult,
-  McpUiOpenLinkResult,
-  McpUiDownloadFileResult,
-  McpUiMessageResult,
-  McpUiResourceTeardownResult,
-  McpUiRequestDisplayModeResult,
-} from "./spec.types.js";
-
 // Re-export all schemas from generated/schema.ts (already PascalCase)
 export {
   McpUiThemeSchema,
@@ -135,106 +108,3 @@ export {
   McpUiToolVisibilitySchema,
   McpUiToolMetaSchema,
 } from "./generated/schema.js";
-
-// Re-export SDK types used in protocol type unions
-import {
-  CallToolRequest,
-  CallToolResult,
-  CreateMessageRequest,
-  CreateMessageResult,
-  CreateMessageResultWithTools,
-  EmptyResult,
-  ListPromptsRequest,
-  ListPromptsResult,
-  ListResourcesRequest,
-  ListResourcesResult,
-  ListResourceTemplatesRequest,
-  ListResourceTemplatesResult,
-  ListToolsRequest,
-  ListToolsResult,
-  LoggingMessageNotification,
-  PingRequest,
-  PromptListChangedNotification,
-  ReadResourceRequest,
-  ReadResourceResult,
-  ResourceListChangedNotification,
-  ToolListChangedNotification,
-} from "@modelcontextprotocol/sdk/types.js";
-
-/**
- * All request types in the MCP Apps protocol.
- *
- * Includes:
- * - MCP UI requests (initialize, open-link, message, resource-teardown, request-display-mode)
- * - MCP server requests forwarded from the app (tools/call, tools/list, resources/list,
- *   resources/templates/list, resources/read, prompts/list)
- * - MCP client requests forwarded to the host (sampling/createMessage)
- * - Protocol requests (ping)
- */
-export type AppRequest =
-  | McpUiInitializeRequest
-  | McpUiOpenLinkRequest
-  | McpUiDownloadFileRequest
-  | McpUiMessageRequest
-  | McpUiUpdateModelContextRequest
-  | McpUiResourceTeardownRequest
-  | McpUiRequestDisplayModeRequest
-  | CallToolRequest
-  | ListToolsRequest
-  | ListResourcesRequest
-  | ListResourceTemplatesRequest
-  | ReadResourceRequest
-  | ListPromptsRequest
-  | CreateMessageRequest
-  | PingRequest;
-
-/**
- * All notification types in the MCP Apps protocol.
- *
- * Host to app:
- * - Tool lifecycle (input, input-partial, result, cancelled)
- * - Host context changes
- * - MCP list changes (tools, resources, prompts)
- * - Sandbox resource ready
- *
- * App to host:
- * - Initialized, size-changed, sandbox-proxy-ready, request-teardown
- * - Logging messages
- */
-export type AppNotification =
-  // Sent to app
-  | McpUiHostContextChangedNotification
-  | McpUiToolInputNotification
-  | McpUiToolInputPartialNotification
-  | McpUiToolResultNotification
-  | McpUiToolCancelledNotification
-  | McpUiSandboxResourceReadyNotification
-  | ToolListChangedNotification
-  | ResourceListChangedNotification
-  | PromptListChangedNotification
-  // Received from app
-  | McpUiInitializedNotification
-  | McpUiSizeChangedNotification
-  | McpUiSandboxProxyReadyNotification
-  | McpUiRequestTeardownNotification
-  | LoggingMessageNotification;
-
-/**
- * All result types in the MCP Apps protocol.
- */
-export type AppResult =
-  | McpUiInitializeResult
-  | McpUiOpenLinkResult
-  | McpUiDownloadFileResult
-  | McpUiMessageResult
-  | McpUiResourceTeardownResult
-  | McpUiRequestDisplayModeResult
-  | CallToolResult
-  | ListToolsResult
-  | ListResourcesResult
-  | ListResourceTemplatesResult
-  | ReadResourceResult
-  | ListPromptsResult
-  | CreateMessageResult
-  | CreateMessageResultWithTools
-  | EmptyResult;
diff --git a/typedoc.config.mjs b/typedoc.config.mjs
index 4c5baa320..041bf5e67 100644
--- a/typedoc.config.mjs
+++ b/typedoc.config.mjs
@@ -1,5 +1,7 @@
 import { OptionDefaults } from "typedoc";
 
+const BASE_SDK_DOCS = "https://ts.sdk.modelcontextprotocol.io/v2/";
+
 /** @type {Partial<import('typedoc').TypeDocOptions>} */
 const config = {
   name: "MCP Apps",
@@ -28,7 +30,29 @@ const config = {
   ],
   excludePrivate: true,
   excludeInternal: false,
-  intentionallyNotExported: ["MethodSchema", "RequestHandlerExtra"],
+  intentionallyNotExported: ["RequestHandlerExtra"],
+  externalSymbolLinkMappings: {
+    "@modelcontextprotocol/client": {
+      ClientOptions: BASE_SDK_DOCS,
+      ConnectOptions: BASE_SDK_DOCS,
+      DiscoverResult: BASE_SDK_DOCS,
+      ProtocolError: BASE_SDK_DOCS,
+      "Protocol.close": BASE_SDK_DOCS,
+      "Protocol.notification": BASE_SDK_DOCS,
+      ResponseCacheStore: BASE_SDK_DOCS,
+      SdkError: BASE_SDK_DOCS,
+      "SdkErrorCode.MethodNotSupportedByProtocolVersion": BASE_SDK_DOCS,
+      "__type.enforceStrictCapabilities": BASE_SDK_DOCS,
+    },
+    "@modelcontextprotocol/server": {
+      LoggingMessageNotification: BASE_SDK_DOCS,
+      "McpServer.registerTool": BASE_SDK_DOCS,
+      "MessageExtraInfo.classification": BASE_SDK_DOCS,
+      "Protocol.close": BASE_SDK_DOCS,
+      "Protocol.notification": BASE_SDK_DOCS,
+      "SdkErrorCode.UnsupportedResultType": BASE_SDK_DOCS,
+    },
+  },
   blockTags: [...OptionDefaults.blockTags, "@description"],
   jsDocCompatibility: {
     exampleTag: false,
@@ -49,6 +73,7 @@ const config = {
   out: "docs/api",
   plugin: [
     "typedoc-github-theme",
+    "./scripts/typedoc-plugin-base-sdk-links.mjs",
     "./scripts/typedoc-plugin-fix-mermaid-entities.mjs",
     "./scripts/typedoc-plugin-seo.mjs",
     "./scripts/typedoc-plugin-mcpstyle.mjs",