events/mcp_metadata_key library

1. mcpe2e package
2. documentation
3. events/mcp_metadata_key.dart

mcpe2e package

1. Libraries
2. core/mcp_event_executor
3. core/mcp_gesture_simulator
4. core/mcp_screen_capture
5. core/mcp_tree_inspector
6. core/mcp_widget_registry
7. events/mcp_event_type
8. events/mcp_events_core
9. events/mcp_metadata_key
10. mcpe2e
11. platform/mcp_connectivity
12. server/mcp_event_server