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.clinerules

Cline rules for FastAPI

Cline and Roo Code read project rules before they edit. A root `.clinerules` file is the shared place for stack commands, safety limits, and how the agent should use tools. This copy is written for a FastAPI project. This repository is a FastAPI service. Request and response bodies are Pydantic v2 models. Routes stay async and must not block the event loop.

The example uses a balanced, readable style, pragmatic tests, and comments only where the intent is not obvious. Open the generator to make the agent stricter, switch to test-first, quiet the comments, or pick a different file.

The example assumes FastAPI with Pydantic v2 and pytest. It does not assume a specific database. If the project uses SQLAlchemy, Tortoise, or raw SQL, keep that choice.

Customize in the generatorBrowse the library

Example file

Balanced strictness, readable style, pragmatic tests. Download name: .clinerules

# Cline and Roo rules

Project rules for Cline and Roo Code in this FastAPI repository.
Use the project's commands. Do not invent a package manager, and do not run destructive shell commands.

## Tool use

- Read the files you will change before editing them.
- Prefer a focused patch over rewriting a whole file.
- Run the test command from this file after a behavior change, or say why you could not.
- Do not delete generated folders, lockfiles, or migrations unless the task says so.

## Stack

This repository is a FastAPI service. Request and response bodies are Pydantic v2 models. Routes stay async and must not block the event loop.

## Layout

- The app package exposes `app`. Routers live beside it and are included explicitly.
- Pydantic models live next to the route that owns them, or in a schemas module if they are shared.
- Settings are read once. Do not call `os.environ` inside a path operation.

## Commands

- Dev server: `uvicorn app.main:app --reload`
- Tests: `pytest`
- Lint: `ruff check .`
- Format: `ruff format .`

Use the script the repo already defines when it differs from the command above.

## Conventions

- Define request and response bodies as Pydantic v2 models, not bare dicts.
- Use `APIRouter` and `Depends` the way the project already does.
- Path operations that talk to the network or a database are `async def`. Do not run blocking I/O directly inside them.
- Return the response model you declared. Do not leak ORM objects that were not configured for it.
- Status codes match the action. Create is 201, a missing row is 404, a bad transition is 409.
- Type hints are mandatory on new functions.

## Testing

Add or update tests when behavior changes.

Test the route with the project's HTTP client (httpx or TestClient). Cover the success path and one rejection.

## Style

- Optimize for the next reader over the shortest diff.
- Comment only when the why is non-obvious.
- Name things the way neighboring files already do.
- Do not reformat code you did not change.

## Errors

- Fail at the boundary. Do not swallow errors.
- Raise `HTTPException` with a stable detail for expected failures. Unexpected errors should propagate to the server log.

## Scope

- Do the requested task. Do not refactor unrelated code.
- Match the rigor already in the repo. Fix what you touch.
- Ask one clarifying question only when the task cannot be finished without it. Otherwise state the assumption and continue.

## Avoid

- Do not call `time.sleep` or synchronous database drivers inside an async route.
- Do not use Pydantic v1 `validator` decorators in new models.
- Do not catch `Exception` and return a 200.
- Do not disable response-model filtering to hide a serialization bug.

## Done when

- The requested behavior works.
- `pytest` passes and `ruff check .` is clean, or you say which tool the repo does not have.
- The diff stays inside the task.
- You list anything you could not run.

Add it to the project

  1. 01

    Copy a starting file

    Copy the example Cline rules on this page, or open the generator if you want different testing, strictness, or comment rules.

  2. 02

    Save it at .clinerules

    Save it as `.clinerules` at the root of the FastAPI repo. If you use Roo Code rules per folder, copy the body to `.roo/rules/project.md` as well.

  3. 03

    Start a fresh agent session

    Rules files are read when a session starts. A chat that is already open may still be using the old instructions.

  4. 04

    Give it one small task

    Ask for one change a FastAPI agent often gets wrong, such as a route that rejects a bad payload with a 422 instead of trusting the dict. If it ignores the file, confirm the path and start a new session.

Questions about this file

Where do I put Cline rules in a FastAPI repo?

Save it as `.clinerules` at the root of the FastAPI repo. If you use Roo Code rules per folder, copy the body to `.roo/rules/project.md` as well.

Which tools read this Cline rules?

Cline reads `.clinerules`. Roo Code reads `.clinerules` and can also load `.roo/rules`. Other agents ignore this filename.

What does the FastAPI example assume?

The example assumes FastAPI with Pydantic v2 and pytest. It does not assume a specific database. If the project uses SQLAlchemy, Tortoise, or raw SQL, keep that choice.

Does VibeSpell upload my repository?

No. Recipe pages are static, and the generator builds the file in your browser from the options you pick. Your source code never leaves the machine.

Other files for FastAPI

Cline rules for other stacks