Hand Off Work Between Claude Code and Codex

This handoff protocol is an editorial method, not an automatic connection between vendors. A new agent needs the current artifact state and permission boundary. “The other agent said it is done” is not a substitute for inspecting the files.

Make the current changes available through an authorized workspace or patch. Do not include credentials, hidden customer data, or an entire private transcript. Decide whether the next agent is reviewing only or may modify files.

Handoff: “Goal: persistent email label in Cedar Studio. Changed: contact.html and styles/forms.css. No endpoint changes intended. Browser label check passed locally; delivery not tested. Review only: inspect the diff for label association, keyboard order, and accidental scope changes. Return findings; do not edit.”

• State: include the actual revision or patch identifier, not a vague “latest.”
• Evidence: name the command, result, and environment; link a screenshot only as visual evidence.
• Remaining issue: mobile spacing has not been checked at 390px.
• Next action: reproduce the pending viewport check before declaring review complete.

1. Write the goal and protected boundaries at the top of the packet.
2. List changed files, the reason for each, and any existing unrelated modifications.
3. Separate passed, failed, blocked, and unrun checks. Include reproducible steps for an observed failure.
4. Ask the receiving agent to inspect the current state and report any mismatch before continuing. Keep the prior worker available only if clarifications are needed.

The receiver can identify exactly what to review without rebuilding the conversation. If it finds a different file state, the protocol exposes the mismatch early instead of letting two confident summaries conceal it.

Stop the handoff if the receiver cannot access the intended patch, the report claims a test with no result, or the next action requires authority not included in the packet. Ask the owner to resolve the missing state or permission.

• Can a new reader reproduce each reported check?
• Are pending items still visibly pending?
• Does review-only mean no edits, commits, messages, or deployment?