public void invoke(TestBrowser browser) {
                browser.goTo("http://localhost:3333");
                assertThat(browser.pageSource()).contains("Your new application is ready.");
            }
        });
    }

There's a whole chapter here in the documentation about it, you can read it at [Additional Responses in OpenAPI](additional-responses.md){.internal-link target=_blank}.

## OpenAPI Extra

When you declare a *path operation* in your application, **FastAPI** automatically generates the relevant metadata about that *path operation* to be included in the OpenAPI schema.

/// note | "Technical details"

				xhttp.AmzBucketReplicationStatus: "PENDING",
				xhttp.ContentType:                "application/json",
			},
		},
		{
			name: "someempty",
			arg: map[string]string{
				xhttp.AmzRestore:                 "",
				xhttp.ContentMD5:                 mustGetUUID(),
				xhttp.AmzBucketReplicationStatus: "",
				xhttp.ContentType:                "application/json",
			},
		},
	}
	for _, tt := range tests {

https://code.visualstudio.com/ link: https://code.visualstudio.com/docs/python/tutorial-fastapi title: FastAPI Tutorial in Visual Studio Code - author: Apitally author_link: https://apitally.io link: https://blog.apitally.io/fastapi-application-monitoring-made-easy title: FastAPI application monitoring made easy - author: John Philip author_link: https://medium.com/@amjohnphilip link: https://python.plainenglish.io/building-a-restful-api-with-fastapi-secure-signup-and-login-functionality-included-45cdbcb36106...

                "get": {
                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        }
                    },
                    "summary": "Read Current User",
                    "operationId": "read_current_user_users_me_get",

   * You may also specify a tag class like [DerHeader.TAG_CLASS_APPLICATION]. The default tag class
   * is [DerHeader.TAG_CLASS_CONTEXT_SPECIFIC].
   *
   * ```
   * Point ::= SEQUENCE {
   *   x [APPLICATION 0] INTEGER OPTIONAL,
   *   y [APPLICATION 1] INTEGER OPTIONAL
   * }
   * ```
   */
  fun withTag(
    tagClass: Int = DerHeader.TAG_CLASS_CONTEXT_SPECIFIC,
    tag: Long,

                    "hello": {"description": "Not a valid additional response"},
                    "200": {
                        "description": "Successful Response",
                        "content": {"application/json": {"schema": {}}},
                    },
                },
                "summary": "A",
                "operationId": "a_a_get",
            }
        }
    },
}

client = TestClient(app)

                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        },
                        "422": {
                            "description": "Validation Error",
                            "content": {
                                "application/json": {
                                    "schema": {

                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {
                                "application/json": {
                                    "schema": {"$ref": "#/components/schemas/Item"}
                                }
                            },
                        },
                        "422": {

                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {
                                "application/json": {
                                    "schema": {
                                        "title": "Response Read Item Items  Item Id  Get",
                                        "anyOf": [