Android MCP Server

Instructions

Implementation Reference

• src/controllers/automation-tools.ts:216-230 (handler)

  Registration and handler implementation of the 'get_device_state' tool.

  server.registerTool(
    'get_device_state',
    {
      description: 'Get the current tracked state of a device including current app, screen history, and recent actions. Useful for understanding context.',
      inputSchema: {
        device_id: z.string().optional().default('default').describe('Device serial number'),
      },
    },
    async ({ device_id }) => {
      const summary = stateTracker.getStateSummary(device_id || 'default');
      return {
        content: [{
          type: 'text' as const,
          text: JSON.stringify({ success: true, state: summary }, null, 2),
        }],

• src/automation/state-tracker.ts:127-146 (helper)

  The logic that actually computes the state summary for the 'get_device_state' tool.

  getStateSummary(deviceId: string): Record<string, unknown> {
    const state = this.getState(deviceId);
  
    return {
      currentApp: state.currentApp,
      screenHash: state.screenHash,
      lastScreenAge: state.lastScreenTimestamp
        ? `${Math.round((Date.now() - state.lastScreenTimestamp) / 1000)}s ago`
        : 'never',
      screenHistoryLength: state.screenHistory.length,
      recentActions: state.lastActions.slice(-5).map(a => ({
        tool: a.tool,
        ago: `${Math.round((Date.now() - a.timestamp) / 1000)}s`,
      })),
      knownApps: Array.from(state.appStates.values()).map(a => ({
        package: a.packageName,
        visits: a.visitCount,
      })),
    };
  }