{* ../../docs_src/separate_openapi_schemas/tutorial001_py310.py ln[1:15] hl[14] *}

...then the `description` field will **not be required**. Because it has a default value of `None`.

### Input Model in Docs { #input-model-in-docs }

You can confirm that in the docs, the `description` field doesn't have a **red asterisk**, it's not marked as required:

<div class="screenshot">

    response = client.put(
        "/items/5",
        json={"description": "A very nice Item"},
    )
    assert response.status_code == 422, response.text
    assert response.json() == {
        "detail": [
            {
                "loc": ["body", "name"],
                "input": {"description": "A very nice Item"},
                "msg": "Field required",
                "type": "missing",

    "critical": {
      "name": "type:critical",
      "colour": "#E84137",
      "description": "critical questions"
    },
    "question": {
      "name": "type:question",
      "colour": "#EDEDED",
      "description": "general questions"
    },
    "feature": {
      "name": "type:feature_request",
      "colour": "#43952A",
      "description": "feature request"
    },
    "invalid_question": {

			Key:         config.Comment,
			Description: config.DefaultComment,
			Optional:    true,
			Type:        "sentence",
		},
		config.HelpKV{
			Key:         target.WebhookClientCert,
			Description: "client cert for Webhook mTLS auth",
			Optional:    true,
			Type:        "string",
			Sensitive:   true,
		},
		config.HelpKV{
			Key:         target.WebhookClientKey,
			Description: "client cert key for Webhook mTLS auth",

	}

	Help = config.HelpKVS{
		config.HelpKV{
			Key:         browserCSPPolicy,
			Description: `set Content-Security-Policy response header value` + defaultHelpPostfix(browserCSPPolicy),
			Optional:    true,
			Type:        "string",
		},
		config.HelpKV{
			Key:         browserHSTSSeconds,
			Description: `set Strict-Transport-Security 'max-age' amount of seconds value` + defaultHelpPostfix(browserHSTSSeconds),

app = FastAPI()


class Model(BaseModel):
    name: str = Field(alias="alias")


class ModelNoAlias(BaseModel):
    name: str

    model_config = ConfigDict(
        json_schema_extra={
            "description": (
                "response_model_by_alias=False is basically a quick hack, to support "
                "proper OpenAPI use another model with the correct field names"
            )
        }
    )

                    "summary": "A normal example",
                    "description": "A **normal** item works correctly.",
                    "value": {
                        "name": "Foo",
                        "description": "A very nice Item",
                        "price": 35.4,
                        "tax": 3.2,
                    },
                },
                "converted": {

                    },
                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        },
                        "422": {
                            "description": "Validation Error",
                            "content": {
                                "application/json": {

    return client


def test_post_all(client: TestClient):
    data = {
        "name": "Special Offer",
        "description": "This is a special offer",
        "price": 38.6,
        "items": [
            {
                "name": "Foo",
                "description": "A very nice Item",
                "price": 35.4,
                "tax": 3.2,
                "tags": ["foo"],
                "images": [

      <superClass>TrackableBase</superClass>
      <description>
        The {@code &lt;toolchains&gt;} element is the root of the descriptor.
        The following table lists all the possible child elements.
      </description>
      <version>1.0.0+</version>
      <fields>
        <field>
          <name>toolchains</name>
          <version>1.0.0+</version>
          <description>The toolchain instance definition.</description>