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supply-chain-risk-auditor

Audits a project's dependencies for supply-chain risk: version-matched advisories for direct dependencies and the full lockfile tree, abandoned or archived upstreams, npm publisher concentration, and install-time script execution. Use when asked to audit dependencies, assess supply-chain or third-party package risk, or review a dependency tree before an engagement.

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Supply Chain Risk Auditor

Generates a supply-chain risk report for a project's direct dependencies (npm, PyPI,

Go), plus an advisory sweep of everything its lockfile resolves. Two deterministic

scripts do the measuring; your job is the judgment they refuse to automate.

Why the scripts do the measuring, not you

Every figure in this report is a claim about somebody else's project, and hand-collected

figures were measured wrong before this skill was rebuilt around scripts: GitHub

contributor counts said five-plus people maintain lodash where npm's ACL says one, and

gh saw zero downloads for a package that moves 164 million a week. Do not estimate

maintainer counts, downloads, staleness, or CVE history from gh, web search, or

memory — run the collector, and quote what it measured.

The scripts enforce two rules worth knowing before you read their output:

  • Unavailable data is never evidence of risk. Every criterion resolves to

assessed-clean, assessed-flagged, or unassessable-with-a-reason.

  • An absent measurement is never a clean verdict. A run that measured nothing exits

non-zero instead of printing a report that finds nothing.

Workflow

  1. Confirm the target directory has manifests: package.json, pyproject.toml,

requirements*.txt, or go.mod. If none exist, say so and stop — do not audit an

ecosystem this collector does not parse by hand. Lockfiles read for exact versions

and the transitive sweep: package-lock.json/npm-shrinkwrap.json, uv.lock, and

a go 1.17+ go.mod. yarn.lock, pnpm-lock.yaml, and poetry.lock are not read —

the report says so when they are present, and versions fall back to pins or the

latest release.

  1. Check gh auth status. Unauthenticated GitHub allows 60 requests/hour against 5,000,

and the collector makes several per dependency; expect repository criteria to come

back unassessable without it. Say so rather than fixing it silently.

  1. Collect, then render. Put outputs somewhere outside the audited repository unless

asked otherwise:

   uv run {baseDir}/scripts/collect.py <project-dir> --json <out-dir>/findings.json
   uv run {baseDir}/scripts/render.py <out-dir>/findings.json --out <out-dir>/report.md
   

Expect a few minutes for ~50 dependencies — several HTTP requests per dependency,

more with many Go modules, and slower without authenticated gh. If collect.py

exits non-zero, it is refusing to report — relay its message verbatim instead of

retrying or working around it.

  1. Read report.md and findings.json. The report is the deliverable; the JSON carries

the datum behind every verdict when you need to cite one.

  1. Add what the collector cannot, clearly separated from what it measured:
  • A short narrative for this reader: what to act on first, and why.
  • Upgrade paths for advisory findings — check whether the fix is a patch or a major

version away.

  • Replacement candidates for abandoned or archived dependencies. Verify a candidate

exists in the registry before naming it, and label these as judgment, not

measurement.

  • For flagged install scripts: whether npm ci --ignore-scripts is viable for this

project's build.

Style for what you add

Write added prose the way a security report reads, and apply the same register to the

report addendum and the final reply alike — replies get pasted into tickets and reports

verbatim. State the finding, the datum behind it, and the action.

  • Impersonal and declarative: no first or second person ("I ran the collector", "you

should upgrade"), no contractions, no exclamation points.

  • Active voice, with the subject matter as the actor: "upgrading to 1.19.0 clears all

25 advisories", not "it is recommended that axios be upgraded".

  • Objective: no intensifiers or subjective framing ("very", "significant",

"fortunately"), and no guesses about why the project chose what it chose.

  • Tense: past for what the audit did, present for the state of the dependencies,

future for the consequences of acting or not.

  • Constructive: a recommendation names the action and its cost, never a culprit.

If the report-writing:writing-style skill is available in the session, follow it —

it is the full version of this register.

The rendered report carries facts only. The interpretive rules below are instructions

to you, not content for the reader — do not copy them into the deliverable as caveats

or framing.

Reading the report

  • Unassessable is not risk. PyPI publishes no maintainer ACL and Go has no registry;

those rows say what could not be known, not what is wrong.

  • The coverage table bounds every claim. "No advisories" means "none among what was

assessed" — check the assessed count before repeating a clean verdict.

  • Quote figures verbatim. Do not re-derive, round, or embellish the report's

numbers; every one is reproducible from the artifact.

  • Absence from the findings is not endorsement. A dependency with no findings was

measured against these criteria only.

Rationalizations to reject

  • "gh can give me maintainer counts faster than the collector." Measured wrong — repo

contributors and registry publish rights are different populations.

  • "No findings, so the dependencies are safe." Read the coverage table; on PyPI and Go,

half the criteria are structurally unassessable.

  • "The unassessable rows would just confuse the reader; I'll drop them." They are the

boundary of every claim in the report. Dropping them turns partial coverage into a

clean bill of health, which is the failure this skill was rebuilt to prevent.

  • "The version is probably close enough." A range checked at latest-release and a

lockfile-resolved version are different claims; the report labels which one it makes.

Keep the label.

When not to use

  • License compliance auditing.
  • Scanning the target's own source for vulnerabilities or secrets — this skill never

reads dependency source, only registry, advisory, and repository metadata.

  • Judging whether the project installs or builds. The audit is designed to work from

nothing more than the dependency list — manifests and lockfiles — and never installs,

builds, or executes anything. Broken installs and import-time breakage are out of

scope, and worth saying so if the user seems to expect them.

  • Ecosystems other than npm, PyPI, and Go; say the ecosystem is unsupported rather than

improvising an audit for it.

Provenance

Authored by Trail of Bits in trailofbits/skills. The content is mirrored here under its upstream license.

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