# Crumb Debug

> Diagnose Crumb routing faults against the F1-F7 fault matrix (adapter spawn fail / subprocess timeout / schema validation / qa.result missing / self-bias risk / infinite loop / env not propagated). Trigger on "왜 멈췄어?", "에러 났어?", "왜 안 돼?", "어디서 막혔어?", "session stuck", "debug", "fault", "이거 왜 이래?", or signs of trouble (no progress, repeated kinds, error events). Read-only. Returns table + suggested actions per detected fault.

- Skill: `mangowhoiscloud/crumb-debug` (Agent Skill)
- Install (CLI): `npx skillmds@latest add mangowhoiscloud/crumb-debug`
- Raw SKILL.md: https://api.skillmd.com/api/skills/mangowhoiscloud/crumb-debug/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: mangowhoiscloud (https://skillmd.com/u/mangowhoiscloud)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/mangowhoiscloud/crumb-debug

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# /crumb-debug — F1-F7 routing fault diagnosis

When the user reports the session is stuck / broken:

**Preferred path** — call the `crumb_debug` MCP tool with `{session: "<ulid>"}`.

**Fallback path** — `npx tsx src/index.ts debug <session-id>`.

If all clear, the report says `✅ No faults detected.` Otherwise table of detected F1-F7 with evidence + suggested action.

Explicit slash form: `/crumb-debug <session-id>`.

Reference: `src/helpers/debug.ts`, v0.1 §8.2 (F1-F7 fault matrix), `wiki/concepts/bagelcode-fault-tolerance-design.md`.