repro — symptom in, structured bug report out

A raw symptom ("the decisions page is blank") is a weak fix prompt: it forces whoever fixes it to re-derive the environment, the steps, and the expected behavior from scratch, and it leaves nothing behind to prove the bug stays fixed. A structured bug report front-loads that work once, turns into a sharp fix prompt, and — its highest-value output — becomes a failing regression test that pins the defect forever.

This skill produces that report, then offers to scaffold the test. It does not fix the bug — capturing it cleanly is the whole job; hand the report to the fix (or to /systematic-debugging) afterward.

The report format — use this exact structure

Emit the report as one contiguous, pasteable block (no leading > quote markers, no mid-sentence line breaks — Wes pastes these into prompts and issues):

## BUG: <one-line summary — the observable failure, not the guessed cause>

**Severity:** <blocker | major | minor — blocker = data loss/security/prod down>
**Surface:** <page + click path, or route, or CLI command, or SDK method>

**Environment**
- Commit: <short sha> (<branch>)
- Node: <version>  ·  Platform: <os>
- Package/SDK version: <if relevant>
- Browser: <only if a UI bug>

**Steps to reproduce**
1. <exact, replayable step — real values, not "do the thing">
2. ...
3. ...

**Actual**
<what happens — verbatim error, status code, stack line, screenshot ref>

**Expected**
<what should happen, and why you believe that — cite the spec/route/test>

**Evidence**
- <log snippet, failing assertion, network response, file:line>

**First suspicion (optional)**
<one sentence — a lead, explicitly marked as unverified so it doesn't anchor>

Two rules that keep the report honest:

• Summary = the symptom, never the guessed cause. "Decisions page renders blank" is reproducible and verifiable; "DecisionsLedgerInner crashes on null agent" is a theory that may be wrong and will mislead the fixer. Keep the theory in First suspicion, clearly fenced off.
• Steps must be replayable by someone with none of your context. If a step reads "with the right filter set," it's not a step — name the filter and the value.

Fill the fields cheaply — don't interrogate the user

Auto-populate the boring fields before asking the user anything. From C:\Projects\DashClaw:

• Commit + branch: git rev-parse --short HEAD and git branch --show-current
• Node + platform: node -v; platform is win32 (this repo's dev box)
• Version: read package.json version when the bug touches the platform or an SDK surface
• Evidence for API bugs: reproduce the call and capture the real response — curl/the SDK against the local dev server (npm run dev, port 3000) beats quoting from memory
• Evidence for UI bugs: the frontend-verify skill already captures console errors + failed requests to disk — pull the failing route's entry rather than clicking by hand

Only ask the user for what you genuinely can't observe: the intended behavior when it isn't written down anywhere, or repro steps for a flow you can't reach. State your assumptions and proceed rather than stalling on a round-trip.

Then offer the regression test

After the report, offer: "Want me to scaffold a failing regression test that reproduces this?" A bug without a test is a bug that comes back. If yes, follow DashClaw's vitest conventions (they're non-obvious — see the notes below), write the test so it fails on today's code for the bug's reason, and say so explicitly. A regression test that passes before the fix is proving nothing.

Name it after the defect, not the function: __tests__/unit/<area>-<symptom>.regression.test.js.

DashClaw vitest conventions that will trip you up if you skip them:

• Tests live in __tests__/ (unit/integration/smoke). Run the full suite with npx vitest run — targeted runs miss cross-file regressions.
• No jest-dom. Use vitest's own matchers + @testing-library queries.
• @/ resolves to app/. Mock next/navigation for anything that reads route params. A .jsx import can resolve to a .tsx file.
• Postgres numerics come back as strings from the Neon driver — assert on the coerced value, not the raw.
• For guard/policy behavior, prefer adding a vector to the risk-calibration golden suite over a bespoke test — that's where scoring regressions are pinned.

If the test can't be written cheaply (needs live external state, a real browser flow, a paid provider call), say so plainly and describe the manual repro instead of forcing a brittle test — a flaky test is worse than an honest note.

What this skill does not do

• It does not fix the bug. Report, optionally pin with a test, then hand off.
• It does not open a tracker or PR (this repo commits to main; the report is the artifact — paste it into the fix prompt, the maintainer log, or CHANGELOG).
• It does not guess the root cause with confidence. Leads go in First suspicion, fenced and unverified.