git:20260731.d2c2e65 to git:20260818.0164a05

24 added, 0 removed. Audit A to A.

# CLAUDE.md

Arthur Engine is an AI/ML monitoring and governance platform. Each component has its own CLAUDE.md with commands and gotchas:

- [genai-engine/](genai-engine/CLAUDE.md) — FastAPI REST API for LLM evaluation and guardrailing (Python 3.12, PostgreSQL + pgVector)

- [genai-engine/ui/](genai-engine/ui/CLAUDE.md) — React 19 + TypeScript + Vite frontend

- [ml-engine/](ml-engine/CLAUDE.md) — job-based evaluation engine for ML model monitoring (Python 3.13)

- [arthur-observability-sdk/](arthur-observability-sdk/CLAUDE.md) — Python SDK for tracing and prompt management

## Workflow

- `dev` is the default branch: feature branches come from `dev` and PRs target it. `main` is production releases.

- Pre-commit hooks format code and run the unit test suites — a slow or failing commit is usually them, not git.

- GenAI Engine API changes require a changelog entry: `uv run generate_changelog` from `genai-engine/`.

- Repo skills cover environment setup and running the stack: `setup-genai-dev`, `start-genai-backend`, `start-genai-frontend`.

- Full-stack local deployment: [deployment/docker-compose/genai-engine/](deployment/docker-compose/genai-engine/) (`cp .env.template .env`, then `docker compose up`).

+ ## Dependencies

+ Every Python project here is `pyproject.toml` + `uv.lock`, and the two must never disagree. CI installs

+ with `uv sync --frozen`, which replays the lockfile and never looks at the manifest — so a manifest-only

+ change is invisible at runtime while still looking merged. Change a pin, then `uv lock --directory <project>`

+ and commit both files together. Never hand-edit `uv.lock`.

+ `check-dependency-automation` in [the CI workflow](.github/workflows/arthur-engine-workflow.yml) enforces

+ this across all four uv projects via

+ [`.github/scripts/check-lockfile-drift.sh`](.github/scripts/check-lockfile-drift.sh), which you can run

+ locally from the repo root. It reports one of two states:

+ - **STALE** — the manifest resolves but the lock was not regenerated. Run `uv lock` and commit.

+ - **UNRESOLVABLE** — nothing can satisfy the manifest, usually because a *transitive* constraint of

+ another pinned dependency caps the package being bumped (`litellm` caps `openai<3.0.0`; `gliner` caps

+ `transformers`; `presidio-anonymizer` caps `cryptography`). Move the lagging dependency forward — never

+ cap or downgrade the one being updated. If nothing upstream lifts the ceiling yet, add an

+ `allowedVersions` rule in [renovate.json](renovate.json) so Renovate stops re-proposing it, naming the

+ blocker and the condition for removing the cap.

+ Renovate opens PRs that edit the manifest without the lock whenever its lockfile step fails, and offers no

+ way to fail closed — that gate is the only thing that catches it. See the `description` at the top of

+ [renovate.json](renovate.json).

## Code style

Write code that reads like the surrounding code: match its comment density, naming, and idiom.

## Frontend

All UI work uses MUI components styled via `sx` with theme tokens — see [genai-engine/ui/CLAUDE.md](genai-engine/ui/CLAUDE.md) for the rules.