Fix Codex title MCP startup and remote terminal spawning

[SmallSpider0]

Fix Codex title MCP startup and remote terminal spawning

Summary

• Wrap the HAPI MCP stdio bridge with an inline Node proxy when launching it from Codex app-server.
• Keep the proxy inline so compiled/release HAPI does not require an extra sidecar file.
• Replace Bun terminal spawning in remote terminals with Node child_process.spawn, using /usr/bin/script on non-Darwin Unix when available.
• Safely quote $SHELL when constructing the script -c command.

Motivation

Codex app-server can fail to initialize the Bun-backed HAPI MCP stdio bridge, leaving mcp__hapi__change_title unavailable in web sessions. Remote terminal sessions can also close immediately with Terminal stream closed unexpectedly in daemon/web environments.

Notes

• HAPI_NODE_EXECUTABLE can override the Node executable used for the MCP stdio proxy.
• Windows remote terminals remain unsupported, matching the existing behavior.
• Terminal resize is best-effort in the new implementation; fidelity can vary depending on /usr/bin/script availability.

Validation

• bun run --cwd cli typecheck
• cd cli && bun x vitest run src/codex/utils/codexMcpConfig.test.ts src/codex/utils/appServerConfig.test.ts src/codex/codexLocal.test.ts src/codex/utils/appServerEventConverter.test.ts src/codex/utils/terminalEventGuard.test.ts — 79 tests passed
• Codex app-server smoke: HAPI MCP startup reports HAPI_MCP ready using the generated inline proxy args
• Terminal smoke: observed echo HAPI_TERMINAL_OK output and exit 0

Known local test limitation

bun run test was attempted, but this machine is Ubuntu 20.04 and the bundled cli/tools/unpacked/difft binary requires newer GLIBC versions (GLIBC_2.32, GLIBC_2.33, GLIBC_2.34). As a result, only src/modules/difftastic/index.test.ts fails locally; the remaining CLI tests run past that point and the targeted tests for this change pass.

[github-actions]

Findings

• [Major] Standalone installs now require an undeclared node executable for Codex MCP — the returned MCP server always runs node -e ..., while repo docs list Homebrew/prebuilt standalone installs and do not list Node as a runtime requirement for Codex/HAPI. On a standalone HAPI install with Codex available but no node on PATH, the HAPI MCP bridge fails before the child hapi mcp process can start. Evidence cli/src/codex/utils/buildHapiMcpBridge.ts:102.
  Suggested fix:

  const nodeCommand = resolveNodeExecutable();
  const hapiMcpServer = nodeCommand
      ? {
          command: nodeCommand,
          args: ['-e', HAPI_MCP_STDIO_PROXY_SCRIPT, bridgeCommand.command, ...bridgeCommand.args]
      }
      : bridgeCommand;

• [Major] macOS remote terminals no longer get a PTY — resolveTerminalCommand() excludes Darwin from the script(1) path and then createPipeTerminal() spawns the shell with plain pipes, so interactive shells/apps have no controlling TTY on a documented supported platform. Evidence cli/src/terminal/TerminalManager.ts:84.
  Suggested fix:

  if (process.platform === 'darwin') {
      return this.createBunTerminal(terminalId, cols, rows, cwd, shell);
  }
  return this.createPipeTerminal(terminalId, cols, rows, cwd, shell);

• [Major] Resize events are acknowledged but never applied to the running PTY — mutating the parent env object after spawn does not update the child process or the script(1) pseudo-terminal window size, so full-screen tools and line wrapping stay at the original dimensions after web/mobile resize. Evidence cli/src/terminal/TerminalManager.ts:214.
  Suggested fix:

  resize: (nextCols: number, nextRows: number) => {
      pty.resize(nextCols, nextRows);
  }

Summary
Review mode: initial
The diff introduces regressions in Codex MCP startup portability and remote terminal PTY behavior. Node availability is not documented as a HAPI runtime prerequisite, and the terminal replacement loses real PTY behavior on macOS plus resize propagation on Linux/script-backed sessions.

Testing
Not run (automation; review only, and PR code was not executed).

HAPI Bot

[SmallSpider0]

Updated in 925001c to address the bot review:

• The inline MCP proxy now falls back to the original HAPI MCP bridge if no Node executable is available; HAPI_NODE_EXECUTABLE remains supported as an explicit override.
• macOS remote terminals now keep the Bun terminal path so they retain PTY behavior and resize support.
• $SHELL is POSIX-quoted before use with script -c.

Revalidated locally:

• bun run --cwd cli typecheck
• targeted Codex/terminal vitest suite: 79 tests passed
• generated bridge config smoke: Codex app-server reports HAPI_MCP ready
• terminal smoke: echo HAPI_TERMINAL_OK, exit 0

[github-actions]

Findings

• [Major] Linux/script terminals ignore resize after creation — TerminalManager.resize() updates the runtime dimensions and calls terminal.resize(), but the new pipe-backed implementation only mutates the parent-side env object after the child has already spawned. On the default non-Darwin path with /usr/bin/script, the running PTY window size never changes, so full-screen tools and prompt wrapping stay at the original dimensions after web/mobile resize. Evidence cli/src/terminal/TerminalManager.ts:286.
  Suggested fix:

  import { spawn } from "node-pty";
  
  const ptyProcess = spawn(shell, ["-i"], {
      name: "xterm-256color",
      cols,
      rows,
      cwd,
      env
  });
  
  const terminal: TerminalHandle = {
      write: (data) => ptyProcess.write(data),
      resize: (nextCols, nextRows) => ptyProcess.resize(nextCols, nextRows),
      close: () => ptyProcess.kill()
  };

Summary

• Review mode: follow-up after new commits
• The prior Node executable and macOS PTY findings appear addressed in the latest diff. One resize regression remains in the default Linux/script terminal path.

Testing

• Not run (automation; review only). Missing coverage: a TerminalManager test that verifies resize reaches the active PTY/process after creation.

HAPI Bot

[SmallSpider0]

Updated again in 0d36b8d to address the follow-up resize finding:

• The default non-Darwin terminal path now uses a small Python stdlib PTY bridge when python3/python is available.
• Resize requests are forwarded to the active PTY with TIOCSWINSZ and SIGWINCH.
• /usr/bin/script remains only a last-resort fallback when Python is unavailable.

Revalidated locally:

• bun run --cwd cli typecheck
• targeted Codex/terminal vitest suite: 79 tests passed
• generated bridge config smoke: Codex app-server reports HAPI_MCP ready
• terminal smoke: echo HAPI_TERMINAL_OK, exit 0
• terminal resize smoke: after resizing to 100x30, stty size reports 30 100, exit 0

[github-actions]

Findings

• No findings.

Summary

• Review mode: follow-up after new commits
• Reviewed the full latest diff plus the prior bot review context. The earlier Linux resize concern is addressed for the normal non-Darwin path by the added Python PTY bridge; the remaining pipe fallback is explicitly best-effort and only used when Python is unavailable or disabled.
• Residual risk: no repo test currently exercises the new TerminalManager PTY bridge lifecycle/resize behavior.

Testing

• Smoke-checked the Python PTY bridge locally for interactive startup, resize propagation via stty size, and foreground/background process cleanup.
• Not run: bun run --cwd cli typecheck and targeted Vitest suite; bun is not installed in this runner.

HAPI Bot