fix
Bug investigation and resolution workflow. Use when the user mentions: - "fix", "broken", "not working", "bug", "error", "issue", "failing" - debugging, troubleshooting, investigating problems - somet
SKILL.mdskills/fix/SKILL.md
GitHubBug Fix Workflow
Standalone Codex
Skip Claude's !command interpolation below. Run git branch --show-current, git log --oneline -5, and git status --porcelain
explicitly. Create each new agent with spawn_agent, continue a live agent with
send_message, trigger another turn for an idle existing agent with
followup_task, wait with wait_agent, and stop a current turn with
interrupt_agent only when necessary. Never spawn codex-verifier and never
run codex-run.ts from inside Codex.
Writers share the working tree unless the live host explicitly offers isolation. Give every writer non-overlapping ownership and serialize the test-writer, implementer, and verification writer phases. Only read-only reviewers may overlap. Wait until the explorer finishes before starting a test writer; wait until that writer finishes before implementation. Codex implementers are not promised Claude worktree isolation.
Use Context7 only when the user configured it. Otherwise use official library docs through native browsing or inspect the pinned local package and state the fallback. This package does not auto-run unpinned registry MCP packages.
You are in Maestro orchestration mode. Delegate immediately to specialized agents.
Current State
- Branch: !
git branch --show-current 2>/dev/null || echo "unknown" - Recent commits: !
git log --oneline -5 2>/dev/null || echo "no commits" - Uncommitted changes: !
git status --porcelain 2>/dev/null | head -10
Workflow
- Clarify - If the report admits more than one reading (which surface, which environment, what "fixed" looks like), run clarifying rounds through the host's question tool until no fork is left, before exploring; a report that names the file, the symptom, and the expected behaviour skips this. When a round runs and the user named no Linear issue, add one question: create one now (recommended: yes)? Create it per the
shipskill's "Linear issue" step and put its ID in the branch name. Never open a round only for this:/shipcreates the issue anyway - Explore - Spawn
exploreagent to understand the affected codebase area - Reproduce - Spawn
testeragent to create a failing test if possible - Diagnose - Analyze findings to identify root cause. Commits named in the bug report are hypotheses, not conclusions — blame the actually-affected file's history before fixing; regressions often ride in earlier on the same branch as the change that got blamed. Before blaming, fetch the team-knowledge index and read any note whose title matches the error's nouns; the fetch command is in docs/knowledge-system.md (fail-open — skip if
ghis unavailable)- A prediction must name something not yet looked at (another code path, an observable the first hypothesis did not touch). One that restates the symptom or only re-reads the suspect line is rejected.
- The user's own uncommitted edits are hypothesis 1. Test them:
git stash push -u -m <unique-tag>, rerun the reproducer, then restore only the entry this run created, found by its tag (git stash apply --indexit so staged state comes back too, and drop it only after the apply succeeds). Never pop other entries. If the push reports nothing to save, restore nothing. - No fix until the causal chain from trigger to symptom is complete, with file:line evidence at each link. "Somehow X leads to Y" is a gap.
- Implement - Spawn
implementeragent to fix the issue - Verify - Spawn
testeragent to confirm the fix - Learn - If this was a non-obvious fix, the auto-memory system in
~/.claude/CLAUDE.mdcaptures it; for team-wide gotchas use/share-learningto post to the team-knowledge repo
Scope Rules
Follow the AGENTS.md guardrails (Bug Fix Scope, 2-Iteration Limit, Name the Cause, Verify After Every Fix). Only modify files directly related to the bug.
Autonomous fix-verify loop: once the reproducer exists, set
/goal the reproducer test passes and the full suite is green, or stop after 5 attempts
to keep iterating without re-prompting. Keep the 2-iteration scope rule in mind when
choosing the stop clause.
Agent Delegation
Spawn explore and tester first — these accept thin prompts because they discover what they need from the codebase:
Agent(explore, "Investigate the bug: $ARGUMENTS. Find relevant files, trace the issue.")
Agent(tester, "Create a failing test that reproduces: $ARGUMENTS")
Claude: then assemble the implementer prompt from the actual outputs. The Claude implementer runs in an isolated worktree with no access to prior agent results, so paste real content — not placeholders, not references:
- The user's original ask (
$ARGUMENTS) verbatim - The exact file paths + line ranges
explorereported (copy them in) - The recommended fix
exploreidentified, quoted line-by-line — not "based on findings" - The build/test command the tester wrote (or repro steps)
- Scope: "only the files listed above; do not refactor adjacent code"
Now spawn:
Agent(implementer, "<the assembled briefing above — all five items inline>")
Agent(reviewer, "Quick review of the fix for quality and edge cases")
Standalone Codex branch: follow the lifecycle and serialization rules at
the top. After implementation and verification finish, a fresh read-only
reviewer supplies the independent pass. Skip the Claude bridge branch below.
Any fix that produced a diff gets a cross-model review in parallel with the reviewer, when the Codex bridge is available — a non-Claude family is the cheapest insurance against a logic error you just wrote:
Agent(codex-verifier, "Cross-model review of the fix diff. Focus on correctness and security. Report findings by severity.")
The bridge fails open: if Codex is unavailable, the reviewer agent alone is fine.
If the codex-verifier spawn fails, or it reports that Bash was stripped (forked skill contexts), run bun "$HOME/.claude/src/scripts/codex-run.ts" review directly instead — never skip the cross-model pass.
Skip the implementer step if explore reports the bug is non-reproducible or
already fixed in current HEAD.
Output
Return a concise summary:
- Root cause: What was wrong
- Fix applied: What changed
- Files modified: List of files
- Verification: How it was tested
- Learning stored: If applicable
Remember
- On an OS, device, vendor, or network blocker, apply the AGENTS.md stop-loss: about 20 minutes or 30 tool calls, then a written diagnosis (ruled out with evidence, likely cause, ranked next options) instead of another attempt
Variant: Merge Conflicts
If the failure is unresolved git merge conflicts (not a code bug), skip the explore/tester loop:
- Detect conflicts:
git diff --name-only --diff-filter=Ulists conflicted paths. - Resolve each conflict with minimal, correctness-first edits. Prefer preserving both sides when safe; otherwise choose the variant that compiles and keeps public behavior stable.
- Regenerate lockfiles with the package manager (
bun install,npm install, etc.) rather than hand-editing. - Run compile, lint, and relevant tests.
- Stage resolved files and summarize key decisions in the commit message.
Guardrails:
- Avoid broad refactors while resolving conflicts — separate PR for cleanup.
Variant: Failing PR CI
If the failure is on a pushed branch with an open PR (not a local bug), use gh pr checks as the source of truth — it covers all PR-attached checks, not just GitHub Actions:
- Resolve the PR:
gh pr view --json number,url,headRefName. - Inspect attached checks:
gh pr checks --json name,bucket,state,workflow,link. - For each failed check, fetch logs:
- GitHub Actions:
gh run view RUN_ID --log-failed. - External services: follow the check
linkto the provider.
- GitHub Actions:
- Extract the first actionable error. Apply the smallest safe fix.
- Push and re-check. The check set can change between runs — re-read
gh pr checksafter every push. To wait for the result, use theshipskill's Step 9 watch; do not write a polling loop.
Guardrails:
- Fix one actionable failure at a time.
- If the failure is clearly unrelated to the PR and already fixed on main, merge main into the branch instead of bloating the PR with unrelated fixes.
- For flaky checks, retry once and report flake evidence rather than chasing a phantom fix.