software-mansion__argent/packages/tool-server/src/index.ts

import { attachRegistryLogger } from "@argent/registry";
import { createHttpApp } from "./http";
import { createRegistry } from "./utils/setup-registry";
import { startSimulatorWatcher } from "./utils/simulator-watcher";
import { DEFAULT_IDLE_TIMEOUT_MINUTES } from "./utils/idle-timer";
import { startUpdateChecker } from "./utils/update-checker";

// ── Config ──────────────────────────────────────────────────────────

const PORT = parseInt(process.env.PORT ?? "3001", 10);
const idleMinutes = parseInt(
  process.env.ARGENT_IDLE_TIMEOUT_MINUTES ?? String(DEFAULT_IDLE_TIMEOUT_MINUTES),
  10
);
const idleTimeoutMs = idleMinutes > 0 ? idleMinutes * 60_000 : 0;

// ── Bootstrap ───────────────────────────────────────────────────────

const registry = createRegistry();
attachRegistryLogger(registry);
const updateChecker = startUpdateChecker();

const { stop: stopWatcher, ready: watcherReady } = startSimulatorWatcher(registry);

let server: ReturnType<typeof httpHandle.app.listen> | null = null;

// `shutdown` closes over `server` by reference — reads the current value when
// called, so it works correctly whether server has started yet or not.
const shutdown = async () => {
  updateChecker.dispose();
  stopWatcher();
  httpHandle.dispose();
  await registry.dispose();
  server?.close();
  process.exit(0);
};

const httpHandle = createHttpApp(registry, {
  idleTimeoutMs,
  onIdle: shutdown,
  onShutdown: shutdown,
});

// Block advertising readiness until the first watcher poll completes — this
// guarantees DYLD_INSERT_LIBRARIES is set in launchd for all currently-booted
// simulators before any agent tool call (e.g. launch-app) can arrive.
watcherReady.then(() => {
  server = httpHandle.app.listen(PORT, "127.0.0.1", () => {
    const addr = server!.address();
    const boundPort = typeof addr === "object" && addr ? addr.port : PORT;
    process.stdout.write(`Tools server listening on http://127.0.0.1:${boundPort}\n`);
    process.stderr.write(`  GET  http://127.0.0.1:${boundPort}/tools\n`);
    process.stderr.write(`  POST http://127.0.0.1:${boundPort}/tools/:name\n`);
    if (idleTimeoutMs > 0) {
      process.stderr.write(`  Idle timeout: ${idleMinutes}min\n`);
    }
  });
});

// ── Lifecycle ───────────────────────────────────────────────────────

process.on("SIGINT", shutdown);
process.on("SIGTERM", shutdown);

// When stdout is piped to a parent that stops reading (e.g. the MCP launcher
// after it captures the startup line), writes via console.log emit EPIPE.
process.stdout.on("error", (err: NodeJS.ErrnoException) => {
  if (err.code !== "EPIPE") throw err;
});
process.stderr.on("error", (err: NodeJS.ErrnoException) => {
  if (err.code !== "EPIPE") throw err;
});