diff --git a/AGENTS.md b/AGENTS.md
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--- a/AGENTS.md
+++ b/AGENTS.md
@@ -1 +1,17 @@
 Security model: [SECURITY.md](./SECURITY.md)
+
+## Building and testing
+
+JMeter builds with Gradle. Use `./gradlew --quiet ...` to reduce output verbosity.
+
+After modifying Java code, before reporting the change as done (handing
+control back to the user), run `./gradlew --quiet classes style` and fix any
+reported issues.
+
+JMeter uses Gradle toolchains; JDKs are found locally or auto-provisioned. The
+code targets JDK 17. To test under a specific JDK pass build parameters:
+
+- `-PjdkTestVersion=<n>` — JDK to run **tests** with; `0` means "use the current Java"
+- `-PjdkTestVendor=<vendor>` / `-PjdkTestImplementation=<impl>` — pin the vendor / VM implementation (jdkTestVersion is enough for most cases)
+
+List every available build parameter with `./gradlew parameters`.