feat(core): Expose __DC_CONTROLLERS__ for programmatic store access via MCP

.changeset/expose-controllers-devtools.md

@@ -0,0 +1,9 @@
+---
+'@data-client/core': patch
+'@data-client/react': patch
+'@data-client/vue': patch
+---
+
+Add `globalThis.__DC_CONTROLLERS__` Map in dev mode for programmatic store access from browser DevTools MCP, React Native debuggers, and other development tooling.
+
+Each [DataProvider](/docs/api/DataProvider) registers its [Controller](/docs/api/Controller) keyed by the devtools connection name, supporting multiple providers on the same page.

.cursor/skills/data-client-react/SKILL.md

@@ -114,6 +114,13 @@ const todosByUser = useQuery(groupTodoByUser);
 
 ---
 
+## Browser Debugging (Chrome DevTools MCP)
+
+To inspect store state, track dispatched [actions](references/Actions.md), or invoke
+[Controller](references/Controller.md) methods from a browser MCP (`user-chrome-devtools`),
+see [devtools-debugging](references/devtools-debugging.md). Uses `globalThis.__DC_CONTROLLERS__`
+available in dev mode.
+
 ## Managers
 
 Custom [Managers](https://dataclient.io/docs/api/Manager) allow for global side effect handling.
@@ -144,5 +151,7 @@ For detailed API documentation, see the [references](references/) directory:
 - [DataProvider](references/DataProvider.md) - Root provider
 - [data-dependency](references/data-dependency.md) - Rendering guide
 - [mutations](references/mutations.md);[_VoteDemo.mdx](references/_VoteDemo.mdx) - Mutations guide
+- [Actions](references/Actions.md) - Store action types (FETCH, SET, etc.)
+- [devtools-debugging](references/devtools-debugging.md) - Debug with Chrome DevTools MCP
 
 **ALWAYS follow these patterns and refer to the official docs for edge cases. Prioritize code generation that is idiomatic, type-safe, and leverages automatic normalization/caching via skill "data-client-schema" definitions.**

.cursor/skills/data-client-react/references/Actions.md

@@ -0,0 +1 @@
+../../data-client-manager/references/Actions.md