Files
Skills/debug/SKILL.md
T
Brummel fc0e1d0d46 skills: cut blabla and redundancy from skill prose
Per-skill prose tightening from the same audit swarm; each finding
passed an adversarial second reviewer. No behavioural change.

- audit: drop garbled "Conventions require deferred audits to
  compound" sentence (says the opposite of intent; the preceding
  line already closes the loophole).
- brainstorm: drop forward-pointing meta-comment about the
  Rationalisations table.
- debug: drop third restatement that debugger.md is the single
  source for the carrier/handoff fields.
- docwriter: drop motivational opener; Overview starts at the
  waste argument.
- fieldtest: fold the 2-4-examples rationale into the dispatch
  sentence instead of restating the count a fourth time.
- implement: drop "known platform constraint at the time" aside.
- planner: cut the verbose anti-drift paragraph (which restated
  the very table it claimed not to) down to a cross-reference.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-05-31 13:21:25 +02:00

3.8 KiB

name, description
name description
debug Use when a bug surfaces — failing test, segfault, wrong stdout, panic, or any observable misbehaviour. Bug fixes are RED-first TDD; no fix is attempted before the failing test exists in the working tree. Mandatory for any bug, including ones that look trivial.

debug — RED-first bug diagnoser

Violating the letter of these rules is violating the spirit.

Overview

Bugs are diagnosed and fixed by a two-stage handoff: this skill produces the RED test and the cause analysis; the implement skill then drives the fix to GREEN. Skipping the RED stage — even for "trivial" bugs — produces fixes that don't stick and tests that don't exist to catch the next regression.

The substantive process — root cause investigation → pattern analysis → minimal, autonomous RED test → handoff, plus the Phase 4.5 architecture-question trigger after three failed hypotheses — lives in agents/debugger.md. The RED stage is not "any failing test": Phase 3 reduces the reproducer to the smallest autonomous trigger before the test counts. That file is the single source of truth for the discipline; this skill file only governs trigger, dispatch, and handoff.

When to Use / Skipping

Trigger this skill on:

  • a failing run of the project's test command (configured under commands.test in the profile)
  • wrong stdout from running a project artefact
  • a segfault from a built binary
  • a panic / unhandled exception in the toolchain
  • a structured diagnostic from bencher or architect that names a concrete misbehaviour

Never skipped. A bug without a regression test is a code change, not a fix. Ad-hoc judgement that a bug is "too small for TDD" is the exact failure mode this skill exists to prevent.

The Iron Law

NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST
NO FIX WITHOUT A FAILING TEST FIRST

Both clauses are non-negotiable.

Dispatch

Dispatch the debugger agent with the carrier fields it defines under Carrier contract in agents/debugger.mdsymptom, repro_known, recent_iter. That table is the authoritative definition of those fields; it is deliberately not restated here, so the two files cannot drift.

The agent writes the RED test to the working tree (uncommitted) and reports the handoff carrier for implement mini-mode. The agent does NOT commit anything, and does NOT write the fix — splitting RED (this skill) and GREEN (implement mini-mode) across two dispatches keeps the diagnosis honest. The orchestrator decides whether to commit the RED test as a separate audit-trail commit before dispatching implement mini-mode, or to hand the dirty working tree directly to mini-mode (the mini-mode orchestrator's Phase-0 clean-tree check will refuse the latter — so for an audit-trail-preserving flow the orchestrator commits the RED test first; for a streamlined-fix flow the orchestrator commits the combined RED+GREEN at the end of mini-mode).

Handoff Contract

debug produces, for implement mini-mode, the handoff carrier the agent defines under Output format in agents/debugger.mdred_test_path, cause_summary, constraint. That list is the authoritative definition of those fields; it is deliberately not restated here, so the two files cannot drift.

Anything else (broader refactor, doc rewrite, new feature) is OUT of scope for the bug-fix iteration and gets queued for a separate one.

Cross-references

  • Agent dispatched: agents/debugger.md — carries the four-phase process, the Phase 4.5 escalation rule, the Common Rationalisations table, and the Red Flags list. The orchestrator does not execute these phases directly.
  • Hand-off target: ../implement/SKILL.md — runs the GREEN side after the orchestrator has decided whether to commit the RED test separately or as part of the final fix commit.