/diagnose

Diagnose before fixing. The debug skill exists but no command orchestrates it. Mixing diagnosis with implementation means the surgeon starts cutting before the X-ray. /kernel:diagnose is the X-ray.

<on_start> agentdb read-start # surface prior failures/gotchas first — a known bug class shortcuts the diagnosis </on_start>

<skill_load> Load: skills/debug/SKILL.md, skills/testing/SKILL.md, skills/architecture/SKILL.md </skill_load>

error, failing test, stack trace, "not working", exception, crash Read error output, failing test, or stack trace. Run the failing command/test to confirm reproduction. If not reproducible, document conditions and ask for more info. Follow the call stack from error to origin. Check recent git changes: git log --oneline --since="3 days" -- {affected files} Identify when the behavior changed. Run failing test in isolation (not full suite). If multiple tests fail, find the minimal reproduction. Binary search: comment out code blocks to narrow the cause. Form 2-3 hypotheses for root cause. For each hypothesis: what evidence would confirm or reject it? Test each hypothesis with minimal code changes or debug output.

    <ask_user>
      Use AskUserQuestion when: hypotheses formed and user may have domain knowledge
      Ask: "Top hypothesis: {hypothesis}. Does this match what you're seeing, or is there context I'm missing?"
      Options: investigate that, I have more context, try a different hypothesis
    </ask_user>
  </step>
  <step id="diagnose">
    Identify confirmed root cause.
    List affected files and blast radius.
    Recommend fix approach (don't implement yet).
    Determine tier based on blast radius.
  </step>
  <step id="handoff">
    Output structured diagnosis.
    Hand off to /kernel:ingest or /kernel:forge for implementation.
    If the user wants to fix immediately, transition to execute mode.
  </step>
</steps>

refactor, restructure, "clean up", "simplify", coupling, dependency Identify all files/modules touched by the refactor target. Use Grep/Glob to find all references. Build a dependency map of what imports/calls what. For each file in the map: who calls this? who depends on it? What breaks if this changes? Identify the blast radius. How tangled is this code with the rest of the system? Count cross-module references. Identify circular dependencies. What are the edge cases in the current implementation? What tests exist? What's untested? What invariants must be preserved? Produce restructuring plan with safety constraints. List files that change, in what order. Identify tests that must pass before AND after. Determine tier based on file count. Output structured diagnosis. Hand off to /kernel:ingest with pre-identified scope.

<output_format>

Diagnosis: {title}

Mode: bug | refactor Root cause: {one sentence} Confidence: high | medium | low

Affected Files

File	Role
{path}	origin — where the bug lives / refactor starts
{path}	downstream — affected by the change

Blast Radius

{N} files affected. Tier {1|2|3}.

Hypotheses Tested (bug mode)

1. "{hypothesis}" → CONFIRMED | REJECTED ({evidence})

Dependency Map (refactor mode)

{what depends on what}

Recommended Approach

{what to do, not how — that's for ingest/forge}

Tests Required

• {test that must pass before the fix}
• {test that validates the fix}

---

Next: /kernel:ingest or /kernel:forge to implement. </output_format>

Record diagnosis event: agentdb emit command "diagnose" "" '{"mode":"bug|refactor","confidence":"high|medium|low","blast_radius":N,"tier":N}'