Please read the [Development - Contributing](https://fastapi.tiangolo.com/contributing/) guidelines in the documentation site....

      including but not limited to software source code, documentation
      source, and configuration files.

      "Object" form shall mean any form resulting from mechanical
      transformation or translation of a Source form, including but
      not limited to compiled object code, generated documentation,
      and conversions to other media types.

That documentation will show up in the Swagger UI at `/docs` in your API, and it will let external developers know how to build the *external API*.

This example doesn't implement the callback itself (that could be just a line of code), only the documentation part.

/// tip

The actual callback is just an HTTP request.

   * serializable.
   *
   * @see <a href=
   *     "http://code.google.com/webtoolkit/doc/latest/DevGuideServerCommunication.html#DevGuideSerializableTypes">
   *     Documentation about GWT serialization</a>
   */
  boolean serializable() default false;

  /**
   * When {@code true}, the annotated type is emulated in GWT. The emulated source (also known as

      including but not limited to software source code, documentation
      source, and configuration files.

      "Object" form shall mean any form resulting from mechanical
      transformation or translation of a Source form, including but
      not limited to compiled object code, generated documentation,
      and conversions to other media types.

from fastapi import FastAPI

app = FastAPI(docs_url="/documentation", redoc_url=None)


@app.get("/items/")
async def read_items():

import java.util.List;

import org.apache.commons.cli.Option;
import org.junit.jupiter.api.Test;

import static java.util.Objects.nonNull;

/**
 * Pseudo test to generate documentation fragment about supported CLI options. TODO such documentation generation code
 * should not be necessary as unit test but should be run during site generation (Velocity? Doxia macro?)
 */
class CLIManagerDocumentationTest {

    * **Facile** : Fait pour être facile à utiliser et apprendre. Moins de temps passé à lire de la documentation.
    * **Concis** : Minimise la duplication de code. Plusieurs fonctionnalités à chaque déclaration de paramètre.
    * **Robuste** : Obtenez du code prêt pour être utilisé en production. Avec de la documentation automatique interactive.

 * provides those capabilities, such as {@link Graph}, {@link ValueGraph}, or {@link Network}.
 *
 * <h3>Additional documentation</h3>
 *
 * <p>See the Guava User Guide for the {@code common.graph} package (<a
 * href="https://github.com/google/guava/wiki/GraphsExplained">"Graphs Explained"</a>) for
 * additional documentation, including <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#notes-for-implementors">notes for

On utilise alors l'argument `deprecated=True` de `Query` :

{* ../../docs_src/query_params_str_validations/tutorial010.py hl[18] *}

La documentation le présentera comme il suit :