Callbacks response_model don't show examples

[Joao-Pedro-P-Holanda]

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Example Code

from pydantic import BaseModel
from fastapi import APIRouter, FastAPI

class CallbackResponse(BaseModel):
    id: int

    model_config = {
        "json_schema_extra": {
            "example": {
                "id": 1
            }
        }
    }

app = FastAPI()
# router used only to document the callbacks used in the endpoint
my_callback_router = APIRouter()

@my_callback_router.get("/", response_model=CallbackResponse)
def get_from_third_party():
    ...

@app.get("/", callbacks=my_callback_router.routes, response_model=CallbackResponse)
def get_from_fastapi():
    return CallbackResponse(id=1)

Description

I am trying to document my utilization of a third party api in Fastapi, but the callbacks are not including the example provided inside a response_model object. It correctly identifies the schema of the response but don't show an example defined
with Pydantic's model_config.

Expected Behavior

What i expected is that callbacks included in a request documentation would show their own responses schemas, likewise the
example from this .yaml file

Operating System

Windows

Operating System Details

Using Windows 11

FastAPI Version

0.111.0

Pydantic Version

2.7.2

Python Version

3.11.5

Additional Context

Currently, if i add the same model to a normal request handler it properly shows the example, but the callback don't behave the same way.

Using the same code provided:

Code

OpenAPI

But on the callback the example is not rendered:

Code

OpenAPI