Code quality

Find bugs across the project

/bug-zero

Run a thorough project-wide bug hunt.

Put it to work

Look across an app for bugs before opening a public beta.

Free and open source under the MIT license.

Code quality002/052Find bugs across the project/bug-zeroRun a thorough project-wide bug hunt.Handoffs

The full skill

Read it before you install it.

This is the complete SKILL.md Claude Code loads. Nothing is held back.

Bug Zero

Point it at code and drive the bugs to zero. It doesn't reinvent bug-finding; it conducts the bug-finders you already have, and adds the trust layer they lack: nothing gets fixed until it's verified real, no fix is banked until it's proven to work and guarded by a test, and the loop stops only when fresh sweeps come up empty.

Core Insight: You already have great bug finders. What's missing is the conductor that makes them trustworthy. The hard part of fixing code with AI isn't finding bugs. It's not hallucinating them, proving a fix actually fixed it without breaking anything else, and knowing when you're done. Like its siblings project-autopilot and ux-maximizer, this is a successive-prompter with a green ratchet: it runs almost no logic of its own; it sequences existing skills and wraps them in verification.

What bug-zero adds (the only new logic)

  1. Multi-modal fan-out: runs the finders together; each catches a bug class the others miss (general / concurrency / fakes / diff / live-process / security).
  2. Adversarial verification: the smart model re-checks EVERY finding against the real code before a single fix. Finders over-report; phantom bugs die here.
  3. Green-ratchet fixing + a regression test per fix: a "fix" that reds any test reverts; every real fix ships with a test that would have caught the bug.
  4. Loop-until-dry convergence: stops on saturation (diminishing real bugs per token), not guesswork and not literal zero.

Preconditions / guards

  1. Baseline must be green: the ratchet needs a known-good starting point. If the suite is ALREADY red at launch, that's an escalation: triage to a green baseline or get the operator's call on what "green" means here before looping. (You can't ratchet from a red baseline.)
  2. Checkpoint first: recoverable starting commit before any fix.
  3. Never weaken tests to reach green. Deleting/skipping assertions to force a pass is forbidden; that hides bugs, it doesn't fix them.
  4. Get a repro first. A symptom that can't be reproduced can't be verified real or proven fixed. Route it to trace-it FIRST (instrument, capture the bad state, return with a located cause); the capture then enters Phase 2 like any other finding. And a LIVE production fire is not a bug pass at all; that's the sibling incident-zero (stabilize before understanding); it hands the post-incident cleanup back here once users are safe.

The Pipeline (staged: issue each step only when the prior finishes)

Phase 0  ORIENT     Read the code + understand intent; establish + checkpoint a
                    green baseline (see guard #1).
Phase 1  SWEEP      Fan out the finders IN PARALLEL, each a different bug class.
                    Dedupe the union of findings. (Roster: references/ROUTING.md.)
Phase 2  VERIFY     Smart-model adversarially re-checks EVERY finding against the
                    actual code. Doubtful ones → multi-model-triangulation /
                    lean-formal-feedback-loop (if installed). Phantom bugs die HERE, pre-fix.
Phase 3  FIX        Fix the survivors one batch at a time (≤5) under the green
                    ratchet, each paired with a regression test that would have
                    caught it. Fix reds a test → revert that batch, move on.
Phase 4  PROVE      Reproduce that the bug is actually GONE (verify skill / run it),
                    not just that tests pass. A fix you didn't watch work isn't one.
Phase 5  RESCAN     Re-sweep. Stop when K=2 consecutive multi-modal passes find
                    nothing real (saturation). Else → back to Phase 2.

Skills it orchestrates

bug-zero is built on the finders you have installed; it adds sequencing + verification, not finders. The non-pack finders below are optional: use each if installed; otherwise the smart model runs that bug-class check itself. Full bug-class → skill map and the staged prompts are in references/ROUTING.md. In brief: repro with trace-it (the un-reproducible symptom is instrumented into evidence before any finder runs); find with ubs / bug-sweep / deadlock-finder-and-fixer / mock-code-finder / code-review / gdb-for-debugging / security-sweep; verify with multi-model-triangulation / lean-formal-feedback-loop; prove with verify / the testing- family; clean up* with simplify / deps-update when the bug was really complexity or a stale dep.

Shared mechanisms (inherited from project-autopilot)

Green ratchet, decision inbox (judgment calls queue for the operator), saturation convergence, and capability-aware execution (solo by default; ntm swarm optional when installed) work as in project-autopilot; see that skill's CONVERGENCE.md / SAFETY-RAILS.md / EXECUTION.md rather than duplicating. Integration: project-autopilot's correctness lens routes a project here for the exhaustive treatment, the same way the UX lens routes to ux-maximizer.

THE EXACT PROMPT

/bug-zero
Target: <project path or file/module>
Scope: <whole project | a subsystem | the current diff>
Mode: solo (default) | swarm (optional; needs ntm installed)

Anti-Patterns

  • Fixing a finding before verifying it's real: the cardinal sin; finders over-report.
  • Running ONE finder. Multi-modal fan-out is the point (each catches what others miss).
  • Claiming "fixed" without reproducing the bug is actually gone.
  • Banking a fix with no regression test: it comes back.
  • Deleting / weakening / skipping tests to reach green: that hides bugs.
  • Ratcheting from an already-red baseline (escalate first; you have no green to hold).
  • Grinding past saturation, or stopping early at literal zero instead of K dry sweeps.

References

  • ROUTING.md: bug-class → finder map, verify/prove/cleanup rosters, staged prompts

Install it in a minute.

Unzip into your Claude Code skills folder, then start a new session. Want the other 51? Grab the whole pack or clone the repo.

unzip bug-zero.zip -d ~/.claude/skills/