First Check

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Example Code

from typing import Annotated
import uvicorn
from fastapi import FastAPI, Query
from pydantic import BaseModel

class MyParams(BaseModel):
    size: int | None = None
    field: list[str] | None = None

app = FastAPI()

@app.get("/items")
async def get_items(
    params: Annotated[MyParams, Query()],
    foo: Annotated[int, Query()],
) -> None:
    print("params: ", params)
    print("foo: ", foo)

if __name__ == "__main__":
    uvicorn.run(app, host="127.0.0.1", port=8000)

Description

Request:

curl --location 'localhost:8000/items?field=foo&field=bar&foo=100'

Expected:
OK

Actual:

{
    "detail": [
        {
            "type": "missing",
            "loc": [
                "query",
                "params"
            ],
            "msg": "Field required",
            "input": null
        }
    ]
}

Operating System

Windows

Operating System Details

No response

FastAPI Version

0.128.7

Pydantic Version

2.12.5

Python Version

Python 3.12.12

Additional Context

No response