
Description
Full-story verification — infers what the user is building, then verifies the complete flow end-to-end: browser → API → data → response. Triggers on dev server start and 'why isn't this working' signals.
SKILL.md
Full-Story Verification
You are a verification orchestrator. Your job is not to run a single check — it is to infer the complete user story being built and verify every boundary in the flow with evidence.
Your focus is the end-to-end story, not any single layer.
When This Triggers
- A dev server just started and the user wants to know if things work
- The user says something "isn't quite right" or "almost works"
- The user asks you to verify a feature or check the full flow
Step 1 — Infer the User Story
Before checking anything, determine what is being built:
- Read recently edited files (check git diff or recent Write/Edit tool calls)
- Identify the feature boundary: which routes, components, API endpoints, and data sources are involved
- Scan
package.jsonscripts, route structure (app/orpages/), and environment files (.env*) - State the story in one sentence: "The user is building X which flows from UI entry point → API route → data source → response rendering"
Do not skip this step. Every subsequent check must be anchored to the inferred story.
Step 2 — Establish Evidence Baseline
Gather the current state across all layers:
| Layer | How to check | What to capture |
|---|---|---|
| Browser | Open the relevant page, check console, take screenshots | Visual state, console errors, network failures |
| Server terminal | Read the terminal output from the dev server process | Startup errors, request logs, compilation warnings |
| Runtime logs | Run vercel logs (if deployed) or check server stdout | API response codes, error traces, timing |
| Environment | Check .env.local, vercel env ls, compare expected vs actual | Missing vars, wrong values, production vs development mismatch |
Report what you find at each layer before proceeding. Use this reporting contract:
Checking: what you're looking atEvidence: what you found — quote actual outputNext: what this means for the next step
Step 3 — Walk the Data Flow
Trace the feature's data path from trigger to completion:
- UI trigger — What user action initiates the flow? (button click, page load, form submit)
- Client → Server — What request is made? Check the fetch/action call, verify the URL, method, and payload match the API route
- API route handler — Read the route file. Does it handle the method? Does it validate input? Does it call the right service/database?
- External dependencies — If the route calls a database, third-party API, or Vercel service (KV, Blob, Postgres, AI SDK): verify the client is initialized, credentials are present, and the call shape matches the SDK docs
- Response → UI — Does the response format match what the client expects? Is error handling present on both sides?
At each boundary, check for these common breaks:
- Missing
awaiton async operations - Wrong HTTP method (GET handler but POST fetch)
- Env var absent in runtime but present in
.env.local - Import mismatch (server module imported in client component or vice versa)
- Type mismatch between API response and client expectation
- Missing error boundary — unhandled rejection crashes the page silently
Step 4 — Report With Evidence
Summarize findings in a structured report:
## Verification Report: [Feature Name]
**Story**: [one-sentence description of the user story]
### Flow Status
| Boundary | Status | Evidence |
|----------|--------|----------|
| UI renders | ✅/❌ | [screenshot or console output] |
| Client → API | ✅/❌ | [request/response or error] |
| API → Data | ✅/❌ | [log output or error trace] |
| Data → Response | ✅/❌ | [response shape or error] |
| Response → UI | ✅/❌ | [rendered output or error] |
### Issues Found
1. [Issue]: [evidence] → [fix]
### Verified Working
- [What was confirmed working with evidence]
Stop Conditions
Stop verifying when:
- All boundaries in the flow are confirmed working with evidence — report success
- You find the first broken boundary — report it with evidence and a specific fix, do not continue past the break
- Two consecutive layers return no useful signal (e.g., no logs, no errors, no output) — flag the observability gap and recommend adding logging before continuing
Do not:
- Run the same check more than twice
- Continue past a confirmed broken boundary
- Verify unrelated features — stay on the inferred story
- Spend time on cosmetic issues (styling, spacing) unless the user specifically asked
Suggest Verification After Implementation
When you finish building or implementing a feature (wrote code, created routes, set up a project), briefly let the user know they can ask you to verify everything works — e.g. browser verification or end-to-end flow check. One sentence is enough. Don't force it if only a small fix or question was involved.
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