| name | dep-guard |
| description | Before adding an import or install command, verify the package/module/API actually exists, instead of trusting a hallucinated name. Use whenever code adds a dependency, an import, or a `pip/npm/cargo install`. Catches hallucinated packages and typosquats (slopsquatting) before they reach the lockfile. Trigger with /dep-guard or "check this dependency", "does this package exist", "verify these imports". |
| version | 0.1.0 |
| user-invocable | true |
| metadata | {"emoji":"📦"} |
dep-guard
LLMs invent package names that look real but do not exist, and attackers pre-register those names (slopsquatting). This skill verifies every new dependency or import against the real registry BEFORE it is added.
Why this exists (evidence)
- LLM-generated code hallucinates package names at a meaningful rate (studies report ~19.7% of suggested packages in some settings do not exist), and the same fake names recur, so attackers register them: "slopsquatting" is a real supply-chain attack vector.
- A hallucinated import is at best a build break, at worst arbitrary code execution from a malicious squatted package.
When to use
- Any new
import / require / use.
- Any
pip install / npm install / cargo add / go get the agent proposes.
- Reviewing AI-generated code that pulls in unfamiliar deps.
The checklist
For each new dependency or import:
- Exists? Confirm the package is real on its registry (npm, PyPI, crates.io, Go modules, Maven). Do not assume from the name.
- Right one? Check it is the intended package, not a typosquat (e.g.
python-dateutil vs dateutils, lodash vs lodahs). Compare owner, downloads, repo link, recent maintenance.
- Standard lib? If the symbol is actually in the language/stdlib, do not add a dependency at all.
- Provenance. Prefer packages with a real repo, downloads, and recent activity. Brand-new, zero-download package matching a "too convenient" name = red flag.
- API exists? For an imported symbol/function, confirm it exists in that package's version, not a plausible-sounding invented method.
- Pin + lock. Add with a pinned version and update the lockfile; never float a freshly added dep.
Verdict per dep: OK (verified real + correct) / TYPO (right idea, wrong name -> correct it) / HALLUCINATED (does not exist -> remove, find the real one) / SUSPICIOUS (exists but unverified provenance -> human check).
How to run it
- Quick: check the registry/page for each new dep (WebFetch / the package manager's
info/view command, e.g. npm view <pkg>, pip index versions <pkg>).
- In CI: pair with a lockfile + allowlist; flag any dep not already trusted.
Composes with
mcp-warden / skill-security-scan: same hostile-data, supply-chain mindset, for MCPs and skills.testsmith: a failing import surfaces fast when tests run.
Honest limits
- It checks existence/provenance, not whether a real package is itself malicious or buggy. A verified package can still be bad; this catches hallucination/typosquat, not full audit.
- Registry checks need network; offline, fall back to "unverified -> human check", never silently trust.
