---
description: "Look-before-build — search registries, repo, existing skills, and web for prior art before implementing. Appends Prior Art to the spec. Use after survey-context and before elaborate-spec, when adding dependencies, or when the task may already be solved."
alwaysApply: false
---

# story: e03s01
# story: e21s02

# Research First

> **HARD GATE** — Do NOT implement until prior art is searched. Minimum outcome: adopt, extend, compose, or build — with evidence.

## Process

1. Read `specs/product/SCOPE_LATEST.yaml`, `specs/release-plan.yaml + epic shards`, and the current task statement.
2. Search in order: this repo → bigpowers skills (`search-skills`) → package registries → web docs.
3. **Check opensrc cache** — if the task integrates an external library, run `bash scripts/bp-opensrc-check.sh` (or `npx opensrc search <pkg>`) to find locally-cached source. Read the `src/` directory for API shapes before writing any integration code.
4. For each candidate: note name, URL/path, fit (adopt | extend | compose | build).
5. Append `## Prior Art` to `requirements/SCOPE_LATEST.yaml` notes or the active epic story.

## opensrc Integration

`opensrc` is a local cache of 200+ open-source repos and npm/PyPI packages. Query it before building any external integration to avoid re-inventing documented API shapes.

```bash
# Check if a package is cached
npx opensrc search <package-name>

# Or use the bundled helper (checks all deps from package.json or requirements.txt)
bash scripts/bp-opensrc-check.sh [package.json|requirements.txt]
```

If opensrc finds a match, read its `src/` or source directory and append findings to the **Prior Art** section:

```
opensrc: found <pkg> v<version> — exports <key classes/functions>
```

If opensrc is not installed or the package is not cached, fall through to web docs normally.

## Outcome matrix

| Verdict | Action |
|---------|--------|
| **adopt** | Use as-is; link in plan; no new code |
| **extend** | Wrap or configure existing solution |
| **compose** | Chain existing skills/modules |
| **build** | New implementation — justify why others failed |

## Verify

→ verify: `grep -rq 'Prior Art' specs/product specs/release-plan.yaml specs/epics 2>/dev/null`

See [REFERENCE.md](REFERENCE.md) for search commands and registry checklist.

---

# Research First — Reference

## Search commands

```bash
# Repo prior art
rg -l "<keyword>" --glob '!node_modules' .
find . -maxdepth 3 -name "SKILL.md" | xargs grep -l "<intent>"

# Installed packages (if package.json exists)
cat package.json | jq '.dependencies,.devDependencies' 2>/dev/null
```

## Registry checklist

- [ ] npm / PyPI / crates.io (if applicable)
- [ ] Existing bigpowers skill (`bash scripts/build-skill-index.sh && rg "<intent>" specs/SKILL-SEARCH-INDEX_LATEST.md`)
- [ ] Project `docs/` and `specs/adr/`
- [ ] Official library documentation (quote one API detail)

## Prior Art template

```markdown
## Prior Art

| Candidate | Source | Verdict | Notes |
|-----------|--------|---------|-------|
| ... | ... | adopt/extend/compose/build | ... |
```