Metro MCP

Get known app sandbox directory paths (documents, cache, temp, library). Returns absolute paths usable with list_directory and read_file.

Get information about the connected React Native app (bundle URL, platform, device name).

Return build-time and runtime flags for the running React Native app: __DEV__, platform, OS version, RN version, Hermes engine, New Architecture, and expo-application fields if available.

Get recent Metro compilation/transform errors.

Get a paged flat React component tree. Follow nextCursor to complete the snapshot and check traversal.complete before treating an empty page as authoritative.

Check the connection status to Metro bundler.

Get recent console output. Filter by level or search text.

Get the currently focused route name and params.

Return a filtered subset of process.env from the running app. Credential-like keys (SECRET, KEY, TOKEN, PASSWORD, etc.) are redacted by default. Use filter to search by key name substring.

Get recent uncaught exceptions from the React Native app.

Return expo-constants manifest/expoConfig fields if the app uses Expo, otherwise null.

Get file or directory metadata: size, modification date, and whether it is a directory.

Return the current profiling results as a human-readable text chart. Shows React DevTools component profile (if captured), CPU flamegraph (if CDP profile captured), and React render data from <Profiler> components (if set up). Call stop_profiling first to populate the profile data.

Get current JavaScript heap memory usage from the running app. Returns used heap, total heap, and heap size limit (when available). Call repeatedly to track memory growth over time or to detect leaks.

Get native platform logs from iOS simulator (syslog) or Android device (logcat).

Get the full React Navigation / Expo Router state tree including current route, params, and stack history.

Get recent network requests from the React Native app.

Get aggregated network statistics: breakdown by domain, status code, and response times.

Return the full Platform.constants object from React Native, including OS-specific build details.

Check whether profiling is active, which mode is in use, and whether a previous profile is available.

Read React render timing data collected via <Profiler onRender={trackRender}>. Returns all recorded renders sorted by actualDuration descending, with memoization savings from baseDuration. Requires importing trackRender from metro-mcp/client. Use clear=true to reset the buffer.

Get recent Redux actions (requires metro-mcp client SDK for real-time tracking).

Get the current Redux state tree or a specific slice. Works without client SDK if Redux DevTools extension is present or store is exposed globally.

Get full details of a specific network request including headers and body.

Get response body for a network request (cached if small; requires active session if large).

Get the navigation back stack / history.

Get the current screen orientation of the device.

Read a specific AsyncStorage key value.

List all AsyncStorage keys in the React Native app.

Get elements with testID or accessibilityLabel. Check traversal.complete before treating an empty elements array as definitive.

Grant a permission to the app on the connected iOS simulator or Android emulator.

Inspect the smallest measured host component at screen coordinates. Uses awaited Fabric/Paper measurement and returns traversal completeness metadata.

Get props, state, and hooks for the first exact component-name match, with traversal completeness metadata.

Install a root certificate on the iOS simulator or Android device.

List all custom commands registered by the app. Commands are registered on global.__METRO_BRIDGE__.commands or global.__METRO_BRIDGE_COMMANDS__.

Auto-discover well-known global debugging objects (Redux stores, Apollo Client, Expo Router, React DevTools hook, etc.) available in the app runtime.

List connected devices and debuggable targets from Metro bundler.

List files and directories in an app sandbox path. Call get_app_directories first to obtain the root path.

Get labelled or interactive elements from the focused React screen. Check traversal.complete before treating an empty elements array as definitive.

List all app permission statuses on the connected iOS simulator or Android emulator. Returns compact text: one name=status line per permission.

List registered route names from available navigation state. Uninitialized nested navigators are not discoverable.

List available iOS simulators or Android emulators.

List all previously saved test recordings in ~/.metro-mcp/recordings/. Returns filenames and sizes. Use load_test_recording to load one for test generation.

List URL schemes registered by an installed iOS app or Android package.

Load a previously saved recording from disk and make it available for test generation. After loading, call generate_test_from_recording with any format to regenerate the test. Use list_test_recordings to see available files.

Long press using a React handler by label/testID, then semantic native input through SimView or IDB when the handler is unavailable. Explicit coordinates use native input directly; native results identify the backend and dispatch state.

Open the connected app's system settings page using React Native Linking.openSettings().

Open a URL or deep link on the connected iOS simulator or Android device.

Open the React Native DevTools debugger panel in Chrome. Connects through the CDP proxy so DevTools and the MCP can share the same Hermes connection.

Press a device button (HOME, BACK, VOLUME_UP, etc.).

Profile a specific JavaScript expression or code path in a single call. Starts profiling, evaluates the expression, waits for it to complete (plus optional extra duration), then stops and returns the top functions by self time. Use instead of calling start_profiling / stop_profiling manually for focused measurements.

Read the contents of a file from the app sandbox. Enforces a configurable size cap (default 50 KB, max 1 MB) to avoid flooding context.

Reload the connected app and verify a fresh runtime. Uses Page.reload, with a directed Metro message fallback only for a verified app/device peer.

Reset one or all permissions for the app on the connected iOS simulator or Android emulator. On iOS, omitting service resets all services. On Android, omitting service resets all runtime permissions.

Revoke a permission from the app on the connected iOS simulator or Android emulator.

Execute a custom command registered by the app. Pass parameters as a JSON object.

Save the current recording events to disk as JSON so they can be reloaded later. Useful for regenerating the same flow in a different test format without re-recording. Files are saved to ~/.metro-mcp/recordings/<filename>.json.

Search network requests by URL pattern, method, or status code.

Writes the Metro CDP connection status script to ~/.claude/metro-mcp-statusline.sh. Does not modify settings.json — tell the user to add it to their status line themselves (e.g. ask Claude: "/statusline add the script at ~/.claude/metro-mcp-statusline.sh"). Only works with Claude Code.

Start Hermes heap allocation sampling via CDP HeapProfiler. Records memory allocation call stacks to identify where objects are being allocated. Call stop_heap_sampling to retrieve the top allocation sites.

Start profiling the running React Native app. Primary path: injects into the React DevTools hook (__REACT_DEVTOOLS_GLOBAL_HOOK__) via evalInApp — captures all component render durations without requiring <Profiler> wrappers, works on all architectures. Fallback (legacy arch only): CDP Profiler domain for JS CPU call-graph sampling. Perform the interaction you want to measure, then call stop_profiling.

Inject interaction interceptors into the running app via the React fiber tree. Captures taps, text entry, long presses, keyboard submits, and scroll/swipe gestures — with no changes to your app code. Works with ScrollView, FlatList, SectionList, FlashList, and other scroll containers. Call stop_test_recording when done, then generate_test_from_recording to get the test.

Stop heap allocation sampling and return the top allocation sites. Shows which functions are allocating the most memory, useful for diagnosing memory leaks. Must call start_heap_sampling first.

Stop profiling and return an analysis of the captured data. DevTools hook mode: returns top components by total render duration across all commits. CDP mode: returns top JS functions by self time and total time. Must call start_profiling first.

Stop the active recording, retrieve all captured events, and store them for test generation. Returns a summary of what was recorded. Call generate_test_from_recording next to produce Appium, Maestro, or Detox test code.

Scroll through React, then use installed SimView or IDB on iOS and the selected ADB serial on Android. Native results identify the backend and dispatch state.

Symbolicate a stack trace using Metro bundler source maps. Converts minified/bundled locations back to original source files.

Capture a screenshot from the connected iOS simulator or Android device.

Tap by label, testID, or logical device-point coordinates. Uses React handlers, then installed SimView or IDB on iOS and adb on Android. Coordinates use native input directly; native results identify the backend and dispatch state.

Type text into an input field. Targets a specific input by testID/label, or the first visible TextInput. Uses the React handler first, then SimView or IDB on iOS and the selected ADB serial on Android.

Poll a JavaScript expression in the app until it returns a truthy value, then return that value. Useful for waiting on state changes, loading flags, API responses, or any async condition. Example: wait for globalThis.myStore?.isLoaded === true.

Poll the component tree until an element matching the given testID or accessibilityLabel appears. Returns element info on success. Use after tap_element, navigate(), or any action that triggers async screen transitions or data loading — instead of immediately calling the next tool. Returns traversal metadata immediately when the bounded search is incomplete.

Poll the active navigation route until it matches the expected route name, then return. Requires the navigation plugin to be set up (get_current_route must work). Use after tap_element on a link or after dispatching a navigate() action.