{"title": "Q", "type": "string"}
                            ),
                            "name": "q",
                            "in": "query",
                        },
                        {
                            "required": False,
                            "schema": {
                                "title": "Skip",

from typing import Union

from fastapi import FastAPI, Query
from typing_extensions import Annotated

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: Annotated[Union[str, None], Query(min_length=3, max_length=50)] = None,
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

            assert data == "Session cookie or query token value is: fakesession"
            data = websocket.receive_text()
            assert data == f"Message text was: {message}, for item ID: foo"
            message = "Message two"
            websocket.send_text(message)
            data = websocket.receive_text()
            assert data == "Session cookie or query token value is: fakesession"

from typing import Annotated, Literal

from fastapi import FastAPI, Query
from pydantic import BaseModel, Field

app = FastAPI()


class FilterParams(BaseModel):
    model_config = {"extra": "forbid"}

    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal["created_at", "updated_at"] = "created_at"
    tags: list[str] = []


@app.get("/items/")

////

`Field` 👷 🎏 🌌 `Query`, `Path` & `Body`, ⚫️ ✔️ 🌐 🎏 🔢, ♒️.

/// note | "📡 ℹ"

🤙, `Query`, `Path` & 🎏 👆 🔜 👀 ⏭ ✍ 🎚 🏿 ⚠ `Param` 🎓, ❔ ⚫️ 🏿 Pydantic `FieldInfo` 🎓.

 & Pydantic `Field` 📨 👐 `FieldInfo` 👍.

`Body` 📨 🎚 🏿 `FieldInfo` 🔗. & 📤 🎏 👆 🔜 👀 ⏪ 👈 🏿 `Body` 🎓.

💭 👈 🕐❔ 👆 🗄 `Query`, `Path`, & 🎏 ⚪️➡️ `fastapi`, 👈 🤙 🔢 👈 📨 🎁 🎓.

///

/// tip

## Import `Field`

First, you have to import it:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning

Notice that `Field` is imported directly from `pydantic`, not from `fastapi` as are all the rest (`Query`, `Path`, `Body`, etc).

///

from fastapi import FastAPI, Query
from pydantic import BaseModel, Field
from typing_extensions import Annotated, Literal

app = FastAPI()


class FilterParams(BaseModel):
    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal["created_at", "updated_at"] = "created_at"
    tags: list[str] = []


@app.get("/items/")
async def read_items(filter_query: Annotated[FilterParams, Query()]):

from fastapi import FastAPI, Query
from pydantic import BaseModel, Field
from typing_extensions import Literal

app = FastAPI()


class FilterParams(BaseModel):
    model_config = {"extra": "forbid"}

    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal["created_at", "updated_at"] = "created_at"
    tags: list[str] = []


@app.get("/items/")

from fastapi import FastAPI, Path, Query
from typing_extensions import Annotated

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    *,
    item_id: Annotated[int, Path(title="The ID of the item to get", ge=0, le=1000)],
    q: str,
    size: Annotated[float, Query(gt=0, lt=10.5)],
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})
    if size:

from typing import List

from fastapi import FastAPI, Query
from pydantic import BaseModel, Field
from typing_extensions import Annotated, Literal

app = FastAPI()


class FilterParams(BaseModel):
    class Config:
        extra = "forbid"

    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal["created_at", "updated_at"] = "created_at"
    tags: List[str] = []


@app.get("/items/")