* If you are comparing Starlette, compare it against Sanic, Flask, Django, etc. Web frameworks (or microframeworks).
* **FastAPI**:
    * The same way that Starlette uses Uvicorn and cannot be faster than it, **FastAPI** uses Starlette, so it cannot be faster than it.

    * This will be used by the **automatic docs**.
    * It will also be used by automatic client code generation tools.

But most importantly:

* It will **limit and filter** the output data to what is defined in the return type.
    * This is particularly important for **security**, we'll see more of that below.

## `response_model` Parameter

```Python hl_lines="9"
{!../../../docs_src/query_params_str_validations/tutorial009.py!}
```

## Déprécier des paramètres

Disons que vous ne vouliez plus utiliser ce paramètre désormais.

Il faut qu'il continue à exister pendant un certain temps car vos clients l'utilisent, mais vous voulez que la documentation mentionne clairement que ce paramètre est <abbr title="obsolète, recommandé de ne pas l'utiliser">déprécié</abbr>.

    It clearly inspired Uvicorn and Starlette, that are currently faster than Sanic in open benchmarks.

!!! check "Inspired **FastAPI** to"
    Find a way to have a crazy performance.

#### Tips and guidelines

    return [pet1, pet2]


client = TestClient(app)


def test_filter_top_level_model():
    response = client.post(
        "/users", json={"email": "******@****.***", "password": "secret"}
    )
    assert response.json() == {"email": "******@****.***"}


def test_filter_second_level_model():
    response = client.get("/pets/1")
    assert response.json() == {

# General - How To - Recipes

Here are several pointers to other places in the docs, for general or frequent questions.

## Filter Data - Security

To ensure that you don't return more data than you should, read the docs for [Tutorial - Response Model - Return Type](../tutorial/response-model.md){.internal-link target=_blank}.

## Documentation Tags - OpenAPI

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="9"
    {!> ../../../docs_src/cookie_params/tutorial001.py!}
    ```

!!! note "Technical Details"
    `Cookie` is a "sister" class of `Path` and `Query`. It also inherits from the same common `Param` class.

    But remember that when you import `Query`, `Path`, `Cookie` and others from `fastapi`, those are actually functions that return special classes.

* 👷 Add CI to test sdists for redistribution (e.g. Linux distros). PR [#11365](https://github.com/tiangolo/fastapi/pull/11365) by [@tiangolo](https://github.com/tiangolo).
* 👷 Update build-docs GitHub Action path filter. PR [#11354](https://github.com/tiangolo/fastapi/pull/11354) by [@tiangolo](https://github.com/tiangolo).

        return {"name": name, "description": "model-a-desc", "foo": model_c}

    client = TestClient(app)
    return client


@needs_pydanticv2
def test_filter_sub_model(client: TestClient):
    response = client.get("/model/modelA")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "name": "modelA",
        "description": "model-a-desc",