# CLAUDE.md - bulkgen development guide

## Project overview

bulkgen is a `make`-like build tool for AI-generated artifacts (images and text). A YAML config file defines targets with dependencies; bulkgen builds a DAG with networkx and executes generation in parallel topological order using Mistral (text) and BlackForestLabs (images) as providers.

## Commands

```bash
uv sync                  # install dependencies
uv run bulkgen build     # build all targets
uv run bulkgen build X   # build target X and its transitive deps
uv run bulkgen clean     # remove generated artifacts + state file
uv run bulkgen graph     # print dependency graph with stages
uv run pytest            # run tests
```

## Code quality

Pre-commit hooks run automatically on `git commit`:
- **pyright** - static type checking (config: `pyrightconfig.json` points to `.devenv/state/venv`)
- **ruff check** - linting with auto-fix
- **ruff format** - formatting
- **commitizen** - enforces conventional commit messages (`feat:`, `fix:`, `chore:`, etc.)

Run manually:
```bash
/nix/store/h7f5vym2ykpl7ls8icw0wiqgmv9xiwnx-pyright-1.1.407/bin/pyright
/nix/store/xmy9vff4zlbvkz3y830085dzgjpmaj8d-ruff-0.14.14/bin/ruff check
/nix/store/xmy9vff4zlbvkz3y830085dzgjpmaj8d-ruff-0.14.14/bin/ruff format --check
```

## Code style conventions

- **All function signatures must be fully typed.** No `Any` unless truly unavoidable.
- Use `pathlib.Path` everywhere, never `os.path`.
- Use `from __future__ import annotations` in every module.
- Use modern typing: `str | None` (not `Optional[str]`), `Self`, `override`, `Annotated`.
- Pydantic `BaseModel` for data that serializes to/from YAML. `dataclass` for internal-only data structures (e.g. `BuildResult`).
- Errors: raise with `msg = "..."; raise ValueError(msg)` pattern (ruff W0 compliance).
- Commit messages follow conventional commits (`feat:`, `fix:`, `refactor:`, `chore:`).

## Architecture

### Module structure

```
main.py                  # Entry point: imports and runs bulkgen.cli.app
bulkgen/
  __init__.py
  cli.py                 # Typer CLI: build, clean, graph commands
  config.py              # Pydantic models for YAML config
  graph.py               # networkx DAG construction and traversal
  builder.py             # Build orchestrator: incremental + parallel
  state.py               # .bulkgen.state.yaml hash tracking
  providers/
    __init__.py           # Abstract Provider base class (ABC)
    image.py              # BlackForestLabs image generation
    text.py               # Mistral text generation
```

### Data flow

1. **cli.py** finds the `*.bulkgen.yaml` in cwd, calls `load_config()` from `config.py`
2. **config.py** parses YAML into `ProjectConfig` (pydantic), which contains `Defaults` and `dict[str, TargetConfig]`
3. **graph.py** builds an `nx.DiGraph` from target dependencies. `get_build_order()` uses `nx.topological_generations()` to return parallel batches
4. **builder.py** `run_build()` iterates generations. Per generation:
   - Checks each target for dirtiness via `state.py` (SHA-256 hashes of inputs, prompt, model, extra params)
   - Skips targets whose deps already failed
   - Runs dirty targets concurrently with `asyncio.gather()`
   - Records state after each generation (crash resilience)
5. **providers/** dispatch by `TargetType` (inferred from file extension)

### Key design decisions

- **Target type inference**: `.png/.jpg/.jpeg/.webp` = image, `.md/.txt` = text. Defined in `config.py` as `IMAGE_EXTENSIONS` / `TEXT_EXTENSIONS`.
- **Prompt resolution**: if the `prompt` string is a path to an existing file, its contents are read; otherwise it's used as-is. Done in `builder.py:_resolve_prompt()`.
- **BFL client is synchronous**: wrapped in `asyncio.to_thread()` in `providers/image.py`. Uses `ClientConfig(sync=True, timeout=300)` for internal polling.
- **Mistral client is natively async**: uses `complete_async()` directly in `providers/text.py`.
- **Incremental builds**: `.bulkgen.state.yaml` tracks per-target: input file hashes, prompt hash, model name, and extra params hash. Any change marks the target dirty.
- **Error isolation**: if a target fails, its dependents are marked "Dependency failed" but independent targets continue building.
- **State saved per-generation**: partial progress survives crashes. At most one generation of work is lost.

### Provider interface

All providers implement `bulkgen.providers.Provider`:
```python
async def generate(self, target_name, target_config, resolved_prompt, resolved_model, project_dir) -> None
```
The provider writes the result file to `project_dir / target_name`.

### Image provider specifics (BFL)

- `image_prompt` field: base64-encoded reference image (from `target.reference_image`)
- `control_image` field: base64-encoded control image (from `target.control_images`)
- Result image URL is in `result.result["sample"]`, downloaded via httpx
- Supported models: `flux-dev`, `flux-pro`, `flux-pro-1.1`, `flux-pro-1.1-ultra`, `flux-kontext-pro`, `flux-pro-1.0-canny`, `flux-pro-1.0-depth`, `flux-pro-1.0-fill`, `flux-pro-1.0-expand`

### Text provider specifics (Mistral)

- Text input files are appended to the prompt with `--- Contents of <name> ---` headers
- Image inputs are noted as `[Attached image: <name>]` (no actual vision/multimodal yet)
- Raw LLM response is written directly to the output file, no post-processing

## Environment variables

- `MISTRAL_API_KEY` - required for text targets
- `BFL_API_KEY` - required for image targets

## Dependencies

- `typer` - CLI framework
- `pydantic` / `pydantic-settings[yaml]` - config parsing (pyyaml comes via the yaml extra)
- `networkx` - dependency graph
- `blackforest` - BlackForestLabs API client (sync, uses `requests`)
- `mistralai` - Mistral API client (supports async)
- `httpx` - async HTTP for downloading BFL result images (transitive via mistralai)
- `hatchling` - build backend