Document the enable_ctx_exports compat flag.

Author: kentonv

src/content/compatibility-flags/enable-ctx-exports.md

@@ -0,0 +1,14 @@
+---
+_build:
+  publishResources: false
+  render: never
+  list: never
+
+name: "Enable ctx.exports"
+sort_date: "2025-09-24"
+enable_flag: "enable_ctx_exports"
+---
+
+This flag enables [the `ctx.exports` API](/workers/runtime-apis/context/#exports), which contains automatically-configured loopback bindings for your Worker's top-level exports. This allows you to skip configuring explicit bindings for your `WorkerEntrypoint`s and Durable Object namespaces defined in the same Worker.
+
+We may change this API to be enabled by default in the future (regardless of compat date or flags).

src/content/docs/workers/runtime-apis/context.mdx

@@ -64,9 +64,15 @@ Here, we've placed a `docId` property in `ctx.props`. The `DocumentApi` class co
 
 ## `exports`
 
+:::note[Compatibility flag required]
+
+To use `ctx.exports`, you must use [the `enable_ctx_exports` compatibility flag](/workers/configuration/compatibility-flags#enable-ctxexports).
+
+:::
+
 `ctx.exports` provides automatically-configured "loopback" bindings for all of your top-level exports.
 
-* For each top-level exports that `extends WorkerEntrypoint` (or simply implements a fetch handler), `ctx.exports` automatically contains a [Service Binding](/workers/runtime-apis/bindings/service-bindings).
+* For each top-level export that `extends WorkerEntrypoint` (or simply implements a fetch handler), `ctx.exports` automatically contains a [Service Binding](/workers/runtime-apis/bindings/service-bindings).
 * For each top-level export that `extends DurableObject` (and which has been configured with storage via a [migration](https://developers.cloudflare.com/durable-objects/reference/durable-objects-migrations/)), `ctx.exports` automatically contains a [Durable Object namespace binding](https://developers.cloudflare.com/durable-objects/api/namespace/).
 
 For example: