Review fails with JSONL parse error: bracketed paste mode escape sequence in output ([?2004h)

[Mingsicogi]

Bug

/codex:review (both foreground and background) fails with a JSONL parse error when the Codex CLI outputs terminal escape sequences (bracketed paste mode) that corrupt the JSON stream.

Error

Failed to parse codex app-server JSONL: Unexpected token '', "[?2004h" is not valid JSON

Reproduction

1. Authenticate with codex login
2. Have a working tree with staged/unstaged changes
3. Run /codex:review from Claude Code (either foreground or background mode)
4. The companion script (codex-companion.mjs) attempts to parse the Codex CLI stdout as JSONL
5. Terminal escape sequence [?2004h (bracketed paste mode) is included in the output, breaking JSON parsing

Both foreground and background execution produce the same error:

# Foreground
node "codex-companion.mjs" review
# → Failed to parse codex app-server JSONL: Unexpected token '', "[?2004h" is not valid JSON

# Background (via Claude Code Bash tool with run_in_background: true)
node "codex-companion.mjs" review
# → Same error

Root Cause

[?2004h is the ANSI escape sequence for enabling bracketed paste mode, typically emitted by shells (bash/zsh) during initialization. When the Codex CLI spawns a subprocess or the shell environment leaks these escape codes into stdout, the JSONL parser in the companion script receives non-JSON data and fails.

This likely happens because:

• The user's shell profile (.zshrc / .bashrc) emits escape sequences on startup
• The Codex CLI subprocess inherits the terminal settings and outputs control sequences
• The companion script does not strip ANSI escape sequences before parsing JSONL lines

Suggested Fix

Strip ANSI escape sequences from the Codex CLI output before attempting JSONL parsing. For example:

// Before parsing each line as JSON
const ansiRegex = /\x1b\[[0-9;]*[a-zA-Z]|\x1b\][^\x07]*\x07/g;
const cleanLine = rawLine.replace(ansiRegex, '').trim();
if (!cleanLine) continue; // skip empty lines after stripping
const parsed = JSON.parse(cleanLine);

Environment

• macOS 15.5 (Darwin 24.6.0)
• Claude Code (CLI)
• Node.js (via Claude Code Bash tool)
• Shell: zsh
• codex-plugin-cc: latest
• Codex CLI: authenticated and working (codex login successful)

Additional Context

• Other review-related issues (Review fails due to unknown sandboxing variant #3 sandbox variant, EISDIR crash in working-tree review when untracked directories exist #14 EISDIR, The Codex plugin review erros because it can't execute shell commands due to bwrap permissions. #18 bwrap) are unrelated — this is a pure output parsing issue.
• The review job log shows Starting Codex Review. and then immediately fails, suggesting the error occurs during the initial JSONL handshake with the Codex app-server.

[deepak-imh]

Fix submitted in #171.

Root cause: Shells (zsh/bash) emit terminal control sequences like \e[?2004h (bracketed paste mode) into subprocess stdout during initialization. The JSONL protocol reader passes these directly to JSON.parse(), which fails.

Fix: Adds a stripAnsi() utility that removes CSI and OSC escape sequences before JSON.parse() in both parsing paths (app-server.mjs handleLine + app-server-broker.mjs socket handler). 7 new tests, all 73 existing tests pass.