Pin ruff at 0.16.4, tightening the floor to an exact version

[lchoquel]

Part of the workspace-wide ruff 0.16.4 rollout (wip/updates/ruff-0.16.4-workspace-rollout-20260814.md). Repo 4 of the scoped batch of seven, after cocode#83, pipelex-starter-python#68 and kajson#58.

Why

Ruff 0.16 lints pyproject.toml itself, and the Ruff VS Code extension syncs config files to the language server. A pre-0.16 binary parses those TOML documents as Python source and paints phantom Ruff(invalid-syntax) diagnostics on lines like requires-python — read as requires - python, an invalid assignment target. The extension runs whatever binary it finds, repo venv first, so the venv pin is what has to move.

This repo carried a >=0.6.8 floor rather than an exact pin, so the venv resolved to whatever was current at lock time (0.15.20 here) while the editor ran 0.16.4. That is precisely the drift an exact pin prevents, and it is the convention the rest of the workspace has settled on.

What changed

pyproject.toml: ruff>=0.6.8 → ruff==0.16.4, plus the matching uv.lock update, and a changelog entry. That is the whole diff — this was the repo's only ruff pin site.

Fallout: none

Zero lint findings and zero reformatting, as the rollout plan predicted for this repo's small Python surface: the ruff config uses a narrow select list without preview, so none of the new preview rules or the noqa → ruff: ignore[...] migration that dominated the pipelex sweep applies.

One thing worth recording for the repos still to come: 0.16 also formats Python code blocks embedded in Markdown, so the formatter's file count here jumped once the generated skill docs came into scope. They were already conformant, so nothing changed — but in a repo whose Markdown carries less tidy examples this is where the diff shows up, and it interacts with generated-doc freshness checks. gen_skill_docs.py --check still reports every target fresh.

Verification

make agent-check — which here runs the full check chain: shared-reference and target-version lockstep, generated skill-doc freshness across the Claude, Codex and Mistral Vibe targets, ruff format --check, ruff check, pyright and mypy, then the Claude and Codex packaging consistency checks — and make agent-test both pass. make check was re-run after the changelog edit to confirm it does not disturb the packaging checks.

🤖 Generated with Claude Code

---

Summary by cubic

Pins ruff to 0.16.4 to eliminate editor/CLI drift and bogus TOML errors. Previously ruff>=0.6.8 resolved to 0.15.20 in the venv while the Ruff VS Code extension used 0.16.4; now both use 0.16.4.

Details

• Change: pyproject.toml ruff>=0.6.8 → ruff==0.16.4; updated uv.lock and changelog.
• Why: ruff 0.16 lints pyproject.toml; pre-0.16 mis-parses it and shows invalid-syntax diagnostics. An exact pin prevents drift with the extension.
• Impact: Dev-only. No lint findings or formatting changes. 0.16 also formats Python code blocks in Markdown; none changed here.
• Action: Recreate the venv or run uv sync to install ruff==0.16.4.

^{Written for commit a7aa1c8. Summary will update on new commits.}

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge, with the manifest and lockfile consistently pinning Ruff 0.16.4 and no actionable changed-code defects identified.

The dependency declaration and lockfile agree on Ruff 0.16.4, the updated lock entry includes broad platform coverage, and no incompatible repository configuration or changed transitive dependency was established.

_{Reviews (1): Last reviewed commit: "Pin ruff at 0.16.4, tightening the floor..." | Re-trigger Greptile}