{"message": "Hello World"}
```

### Interactive API docs

Now go to <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

You will see the automatic interactive API documentation (provided by <a href="https://github.com/swagger-api/swagger-ui" class="external-link" target="_blank">Swagger UI</a>):

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

for compatibility reasons.
Packages or programs may define additional settings for internal debugging purposes;
for example,
see the [runtime documentation](/pkg/runtime#hdr-Environment_Variables)
and the [go command documentation](/cmd/go#hdr-Build_and_test_caching).

### Go 1.24

Go 1.24 changed the global [`math/rand.Seed`](/pkg/math/rand/#Seed) to be a

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image04.png">
</div>

With this feature from **Pydantic v2**, your API documentation is more **precise**, and if you have autogenerated clients and SDKs, they will be more precise too, with a better **developer experience** and consistency. 🎉

## Do not Separate Schemas

* 📝 Add documentation for redefined path operations. PR [#4864](https://github.com/tiangolo/fastapi/pull/4864) by [@madkinsz](https://github.com/madkinsz).
* 📝 Updates links for Celery documentation. PR [#4736](https://github.com/tiangolo/fastapi/pull/4736) by [@sammyzord](https://github.com/sammyzord).

* **Validate data**: coming from each request:
    * Generating **automatic errors** returned to the client when the data is invalid.
* **Document** the API using OpenAPI:
    * which is then used by the automatic interactive documentation user interfaces.

This might all sound abstract. Don't worry. You'll see all this in action in the [Tutorial - User Guide](tutorial/index.md){.internal-link target=_blank}.

	buf []byte
}

func (r *eofReader) Read(p []byte) (int, error) {
	read := copy(p, r.buf)
	r.buf = r.buf[read:]

	switch read {
	case 0, len(r.buf):
		// As allowed in the documentation, this will return io.EOF
		// in the same call that consumes the last of the data.
		// https://godoc.org/io#Reader
		return read, io.EOF
	}

	return read, nil
}