# Create data models

https://docs.serverpod.dev/next/get-started/models-and-data

On the [previous page](https://docs.serverpod.dev/next/get-started/creating-endpoints.md) your endpoint returned a plain string. Here you'll define a `Recipe` model so the server returns structured, typed data instead. You define the model once in YAML, and Serverpod generates the Dart class plus all the serialization needed between server and client.

Keep `serverpod start` running from the previous page.

## Define a model

Serverpod models are declared in `.spy.yaml` files anywhere under the server's `lib` directory. Create `magic_recipe_server/lib/src/recipes/recipe.spy.yaml`:

```yaml
### Our AI generated Recipe
class: Recipe
fields:
  ### The author of the recipe
  author: String
  ### The recipe text
  text: String
  ### The date the recipe was created
  date: DateTime
  ### The ingredients the user passed in
  ingredients: String
```

Save the file. `serverpod start` regenerates the `Recipe` class for both the server and the client.

:::info
Fields can be primitive types, other models, or a typed `List`, `Map`, or `Set`. See [Working with models](https://docs.serverpod.dev/next/concepts/data-and-the-database/models.md) for the full set of options.
:::

## Return the model from your endpoint

Now update `recipe_endpoint.dart` to return a `Recipe` instead of a `String`.

Import the generated models at the top of the file:

```dart
import '../generated/protocol.dart';
```

Change the method's return type from `Future<String>` to `Future<Recipe>`:

```dart
  Future<Recipe> generateRecipe(Session session, String ingredients) async {
```

Then replace `return responseText;` with a constructed `Recipe`:

```dart
    return Recipe(
      author: 'Gemini',
      text: responseText,
      date: DateTime.now(),
      ingredients: ingredients,
    );
```

Save the file. The client regenerates so `generateRecipe` now returns a `Recipe`.

## Show it in your app

In `recipe_screen.dart`, the call now returns a `Recipe` object, so assigning `result` to a string no longer compiles. `_resultMessage` itself stays a `String?`; you just format the `Recipe`'s fields into it. In `_callGenerateRecipe`, update the success `setState`:

```dart
      setState(() {
        _resultMessage = '${result.author} on ${result.date}:\n${result.text}';
        _loading = false;
      });
```

Save. Because the model and the endpoint's return type changed, the generated client changed too, so hot reload isn't enough.

In the `serverpod start` terminal:

- Press **R** to hot restart.

Enter some ingredients and tap **Generate Recipe**. The result now shows the author and date alongside the recipe:

![Flutter Recipe App](https://docs.serverpod.dev/img/getting-started/flutter-web-ingredients.png)

## Next steps

Your endpoint now returns structured data. Next, you'll store recipes in the database so they persist between sessions, and list them in the app.