Android MCP

import assert from 'node:assert'; import { spawn } from 'node:child_process'; import { setTimeout as delay } from 'node:timers/promises'; type JsonRpcResponse = { jsonrpc: '2.0'; id: number; result?: any; error?: any }; function encodeRequest(id: number, method: string, params: Record<string, unknown> = {}) { return JSON.stringify({ jsonrpc: '2.0', id, method, params }) + '\n'; } function createLineParser(onMessage: (msg: JsonRpcResponse) => void) { let buffer = ''; return (chunk: Buffer) => { buffer += chunk.toString(); while (true) { const newlineIndex = buffer.indexOf('\n'); if (newlineIndex === -1) break; const line = buffer.slice(0, newlineIndex).trimEnd(); buffer = buffer.slice(newlineIndex + 1); if (!line) continue; const parsed = JSON.parse(line) as JsonRpcResponse; onMessage(parsed); } }; } async function runTest() { const proc = spawn('npx', ['--yes', 'tsx', './src/server.ts'], { cwd: new URL('..', import.meta.url).pathname, stdio: ['pipe', 'pipe', 'pipe'], }); const messages: JsonRpcResponse[] = []; const rawStdout: string[] = []; const parseStdout = createLineParser((msg) => messages.push(msg)); proc.stdout.on('data', (chunk) => { rawStdout.push(chunk.toString()); parseStdout(chunk); }); const stderr: string[] = []; proc.stderr.on('data', (d) => stderr.push(d.toString())); await delay(1000); proc.stdin.write( encodeRequest(1, 'initialize', { protocolVersion: '2024-11-05', clientInfo: { name: 'test-client', version: '0.0.1' }, capabilities: {}, }), ); proc.stdin.write(encodeRequest(2, 'tools/list')); const deadline = Date.now() + 5000; while (messages.length < 2 && Date.now() < deadline) { await delay(50); } proc.kill(); if (messages.length < 2) { throw new Error( `Timed out waiting for responses. stderr=${stderr.join( '', )} stdout=${rawStdout.join('')}`, ); } const init = messages.find((m) => m.id === 1); assert(init?.result?.serverInfo?.name === 'android-mcp', 'serverInfo missing or wrong'); const tools = messages.find((m) => m.id === 2); if (!Array.isArray(tools?.result?.tools)) { throw new Error(`tools/list did not return an array: ${JSON.stringify(tools)}`); } assert((tools.result.tools as unknown[]).length > 0, 'no tools returned'); } await runTest();