Don't emit terminalSequence outside Claude Code

[jjwjr94]

The problem

terminalSequence is a Claude Code-specific hook output field (added in CC 2.1.141). Other harnesses run Claude Code-format hooks but reject unknown keys in hook stdout — so emitting it there produces a visible error instead of a notification.

Codex is the concrete case. It maps hooks/hooks.json onto its own event names and registers all five of this plugin's hooks:

$ codex app-server  # hooks/list
registered hooks: 5
  warp@claude-code-warp:hooks/hooks.json:post_tool_use:0:0      -> on-post-tool-use.sh
  warp@claude-code-warp:hooks/hooks.json:user_prompt_submit:0:0 -> on-prompt-submit.sh
  warp@claude-code-warp:hooks/hooks.json:session_start:0:0      -> on-session-start.sh
  warp@claude-code-warp:hooks/hooks.json:stop:0:0               -> on-stop.sh
  warp@claude-code-warp:hooks/hooks.json:permission_request:0:0 -> on-permission-request.sh

Codex runs hooks with no controlling tty, so emit_terminal_sequence() takes its "unknown CC version" branch, the /dev/tty write fails, and it prints the JSON. Codex's hook output schema has no terminalSequence and denies unknown fields, so the user gets:

• Hook failed
  └ hook returned invalid post-tool-use JSON output
• Hook failed
  └ hook returned invalid user prompt submit JSON output

...on every tool call and every prompt submission. Reproduced directly against all seven scripts — each one emits the field when no tty is available.

The fix

The JSON fallback only fires when CLAUDE_CODE_VERSION is unset. Claude Code always sets CLAUDE_CODE_VERSION (and CLAUDECODE), so inside Claude Code that branch is unreachable; outside it the field is guaranteed invalid. Gating it on a Claude Code env marker means the guess is only made where it can pay off.

No Codex-specific detection — this fixes any current or future harness that borrows the Claude Code hook format.

Verification

All seven hook scripts, no tty, WARP_CLI_AGENT_PROTOCOL_VERSION + WARP_CLIENT_VERSION set:

Scenario	Before	After
No CLAUDECODE, no CLAUDE_CODE_VERSION (Codex)	emits invalid JSON → error	silent ✅
CLAUDE_CODE_VERSION=2.1.278 (normal CC path)	terminalSequence JSON	unchanged ✅
CLAUDECODE=1, version unset (the existing hedge)	terminalSequence JSON	unchanged ✅
CLAUDE_CODE_VERSION=2.0.0 (old CC)	writes to /dev/tty	unchanged ✅

bash -n clean. Plugin version bumped 2.2.0 → 2.2.1 in both plugin.json and marketplace.json, matching the convention in #73.

Note on a related gap

Warp notifications from Codex don't currently work at all — the OSC sequence has no route to the terminal there, since Codex hooks have no tty and no output field for one. This PR only stops the errors. Delivering notifications under Codex would need a separate mechanism, happy to file that as an issue if useful.

🤖 Generated with Claude Code