| name | pypi-ops |
| description | Publish Python packages to PyPI via OIDC Trusted Publishing (PEP 740 attestations, gh-action-pypi-publish) instead of stored tokens. Use for: invalid-publisher errors, pending-publisher 404s, uv publish/twine, TestPyPI, environment approval gates, and rotating/auditing publish tokens. |
| license | MIT |
| compatibility | Python 3.8+ packaging; GitHub Actions for the OIDC flow; uv or twine for local publish |
| allowed-tools | Read Write Edit Bash Glob Grep WebFetch |
| metadata | {"author":"claude-mods","related-skills":"supply-chain-defense, github-ops, git-ops, ci-cd-ops, python-env"} |
PyPI Operations
Publish Python packages to PyPI on the 2026 best-practice path: OIDC Trusted
Publishing with signed PEP 740 attestations, no long-lived token to leak. This
skill owns the publish layer (the registry handshake, the first-publish
gotchas, the recovery playbook). General GitHub Actions syntax is ci-cd-ops;
the install-side worm defense is supply-chain-defense; gh/release-page
mechanics are github-ops.
Where this fits — the release pipeline
A release spans several skills; pypi-ops owns the registry step. Chain them:
- Vet dependencies before cutting a release —
supply-chain-defense
(cooldown + behavioural scan). The build runs dependency code before it
touches your publish credential, so a poisoned build dep can steal the token.
- Preflight —
scripts/publish-preflight.sh --build . (this skill).
- Bump → tag → push —
git-ops (its push-gate scans for secrets / forbidden
files before the tag goes up).
- CI publishes via OIDC — this skill's
assets/publish.yml; you approve at
the pypi environment gate.
- Release page (optional, GitHub) —
github-ops, human-reviewed notes.
The one decision: OIDC vs API token
Default to OIDC Trusted Publishing. Reach for a token only when OIDC is
impossible (publishing from a non-supported CI, or a one-off local push).
| Trusted Publishing (OIDC) ← default | API token |
|---|
| Secret stored | None — short-lived OIDC token minted per run | Long-lived pypi-… token in a secret |
| Leak/phish blast radius | None to steal | Full publish rights until rotated |
| Provenance | PEP 740 attestations (signed, verifiable) | None by default |
| Setup | One-time publisher registration on PyPI | Generate token + store secret |
| Best for | All CI/CD releases | Legacy CI, emergency local upload |
If a repo currently uses a token, migrating to OIDC is strictly an upgrade — see
references/trusted-publishing.md.
The #1 gotcha: first publish needs a pending publisher
A Trusted Publisher is normally configured under the project's settings on
PyPI — but on the first ever publish the project doesn't exist yet, so there's
nothing to configure it under. The fix is a pending publisher, registered at
the account level before the first upload.
Symptom (the exact failure this skill exists to kill):
Trusted publishing exchange failure:
* invalid-publisher: valid token, but no corresponding publisher
(Publisher with matching claims was not found)
The OIDC token was valid; PyPI just has no publisher matching the claims. Fix:
PyPI → https://pypi.org/manage/account/publishing/ → Add a pending publisher
| Field | Value |
|---|
| PyPI Project Name | the dist name from pyproject.toml [project].name |
| Owner | GitHub org/user |
| Repository name | repo name |
| Workflow name | the filename, e.g. publish.yml (not the name:) |
| Environment name | must equal the job's environment: (e.g. pypi) |
All four claims must match the run's OIDC token exactly. After the first
successful publish, the pending publisher auto-converts to a normal project
publisher — no further action. Run diagnose-publish.sh on a failed run to read
the exact claims it presented and compare them field-by-field.
This is the most common silent-failure mode: a package's publish.yml looks
perfect and every release builds green, yet nothing ever reaches PyPI because
the publisher was never registered. Check it first.
The shipped template is hardened to the patterns below — adapt the marked points
and drop it in .github/workflows/. Non-negotiables it encodes:
on: push: tags: ['v*'] — release on a version tag, never on every push.
- OIDC, no token: the
publish job has permissions: id-token: write and
pypa/gh-action-pypi-publish with attestations: true. No password:/token.
environment: pypi on the publish job → a human approves every release
(defense-in-depth: even a compromised repo can't auto-ship).
- Build/publish split: a
build job (no elevated perms) produces + uploads
the dist artifact; publish downloads it. Least privilege per job.
uv sync --locked + pip-audit: the release is built against the
committed, hash-verified lockfile and blocked if a dep has a known CVE.
twine check / metadata validation before upload.
- SHA-pinned actions with a trailing
# vX comment (mutable tags get
hijacked — see check-action-pins.py).
- Verify-on-PyPI tail job — polls the JSON API so a silent publish failure
(accepted-but-not-live, CDN lag) surfaces loudly instead of looking fine.
Supply-chain hardening — the publisher side
Stealing your publish credential lets an attacker ship malware to everyone who
installs you — so the publish path is the surface the 2026 worm campaign (Mini
Shai-Hulud) targets, minting PyPI/npm tokens from stale OIDC trust and orphaned
workflows. The template above isn't just convention; each choice is a defense:
| Control | Defends against |
|---|
| OIDC, no stored token | Credential theft/phishing — there is no long-lived secret to steal |
| PEP 740 attestations | Tampered artifacts — provenance is signed and verifiable |
environment: pypi + reviewers | A compromised repo/CI auto-shipping — a human still gates the release |
pip-audit gate | A knowingly-vulnerable dependency reaching the release build |
SHA-pinned actions (check-action-pins.py) | Action-tag hijacks (tj-actions, 2025) repointing @vN to a malicious commit |
permissions: {} + per-job least privilege | A poisoned build step escalating beyond read |
uv sync --locked | Build-time dependency injection / silent re-resolution |
Then audit the trust itself, not just the workflow:
- Revoke stale Trusted Publishers / OIDC federation you no longer use — an
orphaned publisher bound to a deletable workflow is the Mini Shai-Hulud entry
point. Review PyPI → project → Publishing periodically.
- If a token is in play, rotate it (project-scoped, short-lived) — better,
migrate to OIDC and delete it. See trusted-publishing.md.
- Vet build dependencies before a release, not after — a poisoned
uv sync
step runs before your OIDC token is even minted.
Division of labour: pypi-ops owns publisher hardening; supply-chain-defense
owns the install side and ships integrity-audit.sh (hunts pull_request_target
- OIDC misconfig and worm persistence) — run it on any repo that publishes, and
gate dependency bumps through its cooldown + behavioural scan.
Cutting a release — preflight then tag
Before tagging, run the preflight so a release never fails on something
mechanical (version skew, dirty lock, missing publisher config):
scripts/publish-preflight.sh .
scripts/publish-preflight.sh --build .
scripts/publish-preflight.sh --json . | jq '.data[] | select(.ok==false)'
It checks: pyproject version == __init__.__version__, the version is not
already on PyPI (uploads are immutable — you cannot re-push 1.2.3), the
lockfile self-version matches, a tag (if present) matches the version, and the
publish workflow uses OIDC (flags a stored token). --build additionally
verifies the package actually builds and passes twine check. Dynamic-versioned
projects (hatch-vcs / setuptools-scm) are read from the HEAD tag. Green → bump,
commit, tag, push the tag; CI builds, waits at the pypi environment gate, you
approve.
When a publish fails — classify, don't guess
scripts/diagnose-publish.sh <run-id>
gh run view <run-id> --log-failed | scripts/diagnose-publish.sh -
The high-frequency failure classes and their fixes:
| Symptom | Cause | Fix |
|---|
invalid-publisher / claims not found | No (pending) publisher on PyPI | Register the pending publisher (above) |
File already exists / 400 on upload | Version already on PyPI (immutable) | Bump the version; never reuse — see recovery |
| Job stuck "Waiting" | environment: pypi needs approval | Approve the deployment in the run's UI |
environment … not found | Publisher claim names an env the job lacks | Make environment: and the publisher's Environment match |
| Built green, not on PyPI | Silent accept / no verify step | Add the verify-on-PyPI job; re-run |
non-OIDC/token rejected | Token wrong/expired, or OIDC misread as token | Prefer OIDC; if token, rotate + re-store |
Full catalogue with the underlying mechanics: references/recovery-playbook.md.
Local & manual publishing (uv / twine)
For a one-off or a non-CI environment. Prefer uv in 2026 (faster, native):
uv build
uv publish --trusted-publishing automatic
UV_PUBLISH_TOKEN="pypi-…" uv publish
twine remains the canonical fallback and the metadata validator (the GitHub
Action wraps it internally):
python -m twine check dist/*
python -m twine upload dist/*
Never hand-roll the HTTP upload. Details + ~/.pypirc shape:
references/uv-publish.md.
Dry-run on TestPyPI first
For a brand-new package or a risky metadata change, publish to test.pypi.org
first — it has its own separate accounts and its own pending-publisher
registration. Point the action at repository-url: https://test.pypi.org/legacy/
and register the pending publisher on TestPyPI. See
references/trusted-publishing.md.
Keeping the workflow from rotting
The pinned action SHAs and pypa/gh-action-pypi-publish major drift over time.
The verifier flags it before a release does:
scripts/check-action-pins.py --offline .github/workflows/publish.yml
scripts/check-action-pins.py --live .github/workflows/publish.yml
--offline is the PR gate (every uses: is SHA-pinned with a # vX comment);
--live runs scheduled (resolves each pin against GitHub and exits 10 on drift,
7 if GitHub is unreachable — advisory, never a flaky block).
Publishing many packages (a fleet)
When several repos publish the same way, don't copy publish.yml N times — each
copy drifts its own SHA pins. Hoist the publish job into a reusable workflow
(on: workflow_call) in one repo, and have each package's tiny caller pass its
dist name. OIDC still works: the caller's workflow_ref is what PyPI matches,
so register each package's pending publisher against the caller filename
(e.g. release.yml), not the shared one. One place to refresh pins
(check-action-pins.py on the reusable workflow); one approval gate definition;
per-package publishers. See references/trusted-publishing.md
for the claim that must match.
Reference files