implementlisted

# Implement Skill > **Quick Ref:** Execute single issue end-to-end. Output: code changes + commit + closed issue. **YOU MUST EXECUTE THIS WORKFLOW. Do not just describe it.** Execute a single issue from start to finish. ## Codex Lifecycle Guard When this skill runs in Codex hookless mode (`CODEX_THREAD_ID` is set or `CODEX_INTERNAL_ORIGINATOR_OVERRIDE` is `Codex Desktop`), ensure startup context before claiming or implementing the issue: ```bash ao codex ensure-start 2>/dev/null || true ``` `ao codex ensure-start` is the single startup guard for Codex skills. It records startup once per thread and skips duplicate startup automatically. Leave `ao codex ensure-stop` to dedicated closeout skills such as `$validation`, `$post-mortem`, or `$handoff`. ## Execution Steps Given `$implement <issue-id-or-description>`: ### Step 0: Pre-Flight Checks (Resume + Gates) **For resume protocol details, read `references/resume-protocol.md`.** **For ratchet gate checks and pre-mortem gate details, read `references/gate-checks.md`.** ### Step 0.5: Pull Relevant Knowledge ```bash # Pull knowledge scoped to this issue (if ao available) ao lookup --bead <issue-id> --limit 3 2>/dev/null || true ``` **Apply retrieved knowledge (mandatory when results returned):** If learnings or patterns are returned, do NOT just load them as passive context. For each returned item: 1. Check: does this learning apply to the current issue? (answer yes/no) 2. If yes: treat it as an implementation constr