## What
Adds a **report-only** `Dead Code` CI workflow that surfaces
likely-orphaned code on every PR, across all three surfaces —
TypeScript, Python, and GitHub Actions. Follow-up to the root
`Dockerfile` cleanup (#3783) and the dead-code sweep in #3786: instead
of finding this stuff by hand, catch it automatically.
| Surface | Tool | Wiring |
|---|---|---|
| TypeScript | [**knip**](https://knip.dev) | `knip.json`; runs via
`pnpm dlx knip@5`. Finds unused files, exports, types, and dependencies.
|
| Python | [**vulture**](https://github.com/jendrikseipp/vulture) |
`dead_code` nox session + `make dead-code`; allowlist at
`python/config/vulture_allowlist.py`. Finds unused
functions/classes/variables (complements Ruff's F401/F841). |
| GitHub Actions | small bash script |
`.github/scripts/check-orphan-ci.sh` — flags reusable workflows and
composite actions with no callers. |
## Why report-only (not blocking)
Every job writes findings to the run's **Step Summary** and **never
fails the build**. These tools carry unavoidable false positives on a
library monorepo — public API surface, dynamic imports, import-map
targets (e.g. core's `#platform`), framework entry points. A red ❌ on
false positives would just train everyone to ignore the check. Once a
job's config is refined enough that a clean run is the steady state, it
can be flipped to blocking.
## Validation (ran each locally)
- **knip**: 0 unused *files* after scoping out the e2e-test workspaces
(knip crashes traversing `ts/e2e-tests/**` — pre-existing knip bug,
filed via `ignoreWorkspaces`) and build/docs artifacts. Export/dep
categories surface advisory items.
- **vulture**: clean run (report-only); allowlist suppresses the 3
`TYPE_CHECKING` re-exports in `custom_tool.py`; `build/`/`dist/`
excluded. Surfaces 4 genuine minor items (`bases`, `desc`×3).
- **orphan-CI script**: finds none — the repo has no orphaned CI
plumbing today.
- **Pinning**: `jk actions check` clean for this workflow;
`actions/checkout` is SHA-pinned, the two local composite actions need
no pin.
Local usage is documented under **Dead code detection** in
`CONTRIBUTING.md`.
## Note on scope
These cover TS/Python/GHA — they would *not* have caught the root
`Dockerfile` itself (an arbitrary root file no tool tracks). That class
stays a manual-review concern; the orphan-CI script is the closest
analogue for the CI surface.
Alberto Schiabel