Privacy Check

/privacy-check — Release Privacy Hygiene

You scan the release for obvious personal-data collection signals (email/name/phone/address/payment fields, telemetry libraries) and surface whether a privacy note exists when collection is detected. The output feeds /release-readiness, which gates /ship.

This is not a legal review. It does not certify GDPR or CCPA compliance. It is a deterministic release-hygiene check that catches the easy misses: code that collects email but no privacy note in the README, or a new telemetry import without an opt-out path documented.

This is the privacy-check skill from the compliance-release stack. PR 2 of the Custom Stack Examples v1 round wires the real behavior; this PR (PR 1) ships the skill structure so the static contract validates.

Process

0. Resolve paths (host-agnostic)

NANOSTACK_ROOT="${NANOSTACK_ROOT:-$HOME/.claude/skills/nanostack}"
SKILL_DIR="${SKILL_DIR:-$HOME/.claude/skills/privacy-check}"

1. Run the check

SKILL_DIR="${SKILL_DIR:-$HOME/.claude/skills/privacy-check}"
"$SKILL_DIR/bin/check.sh"

The helper scans the project's source for:

• Personal-data fields: email, name, phone, address, payment, token, api_key, file uploads.
• Telemetry libraries: analytics, tracking, telemetry, segment, posthog, ga, mixpanel, sentry.
• A privacy note: PRIVACY.md, a "Privacy" or "Data" section in README.md, or TELEMETRY.md for telemetry-only cases.
• Env templates: .env.example, .env.sample, .env.template (allowed by guard) for keys that hint at collection.

The helper does not read .env, .env.local, .env.production, or any credential JSON. The bash guard already blocks those.

2. Save the artifact

NANOSTACK_ROOT="${NANOSTACK_ROOT:-$HOME/.claude/skills/nanostack}"
"$NANOSTACK_ROOT/bin/save-artifact.sh" privacy-check \
  '{"phase":"privacy-check","summary":{"status":"WARN","headline":"...","signals":[...],"missing":["privacy_note"],"next_action":"..."},"context_checkpoint":{"summary":"Privacy check completed."}}'

Status rules:

• OK — no collection signals detected, or signals are documented in a privacy note.
• WARN — collection signals detected but no privacy note found, or telemetry without an opt-out path documented.
• BLOCKED — reserved for clearly unsafe patterns (e.g., a credential file added to source). The composer escalates this in /release-readiness.

3. Headline

[privacy-check] WARN: email collection detected, no privacy note.

Gotchas

• This skill does not interpret intent. A test fixture that mentions email will be flagged the same way real code does. The user decides whether the signal is real.
• "Privacy note" is a structural check, not a quality check. The skill confirms a note exists; it does not validate the note's content. That's a human review.
• The helper never edits files, never writes to the network, never opens .env or credential files. Read-only by design.