> For the complete documentation index, see [llms.txt](https://docs.tonic.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tonic.ai/fabricate/data-agent-tools/data-agent-modes-and-models/selecting-the-models-to-use.md).

# Selecting the models to use

From the Data Agent chat, you can select the specific models to use for different types of tasks, based on the model performance and model cost. For example, for a larger data generation job, you might select a lower-cost model.

You also select the level of effort and the maximum number of tokens for the chat context, both of which also affect the performance and cost.

Your account owner can change both the [default and available models for the account](/fabricate/about-fabricate/fabricate-pricing-and-ai-usage/account-default-available-ai-models.md).

To change the selected model and level of effort:

1. Click the current data generation model and effort selection.

<figure><img src="https://4109733485-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FmoU4gTR9LxlzHeWmQCUZ%2Fuploads%2FcsISSI54MI549YnDvrpI%2FDataAgent_ModelSelected.png?alt=media&amp;token=9899865a-6b35-4e58-ab90-7dbeed388370" alt=""><figcaption><p>Current model and effort selection for the Data Agent</p></figcaption></figure>

2. On the **Models** panel, under **Model:**

   1. Under **Data Generation**, click the radio button for the model to use to generate date.&#x20;
   2. If [validation is enabled](/fabricate/data-agent-tools/using-the-validation-agent.md), then under **Validation**, click the radio button for the model to use for validation.

   For both data generation and validation, the default, and the recommended option, is Opus 5.\
   \
   Note that if you use your own LLM provider, and are not connected to Azure AI Foundry, then the GPT models are not available.

<figure><img src="https://4109733485-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FmoU4gTR9LxlzHeWmQCUZ%2Fuploads%2Fgk8RWhSTscDZWLONZOIA%2FDataAgent_ModelSelection.png?alt=media&amp;token=d9e89bef-26a0-4268-82a2-607f269e6bd2" alt=""><figcaption><p>Models panel with the model and effort selection</p></figcaption></figure>

3. Under **Effort**, click the radio button for the level of effort to use. The default is **High**.
4. Under **Freeform text model**, click the radio button for the model to use to generate freefrom text.\
   \
   The default, and the recommended option, is Gemini 3.5 Flash Lite.
5. From the **Context Window** dropdown list, select the maximum number of tokens for the chat context.\
   \
   The default is 200,000 tokens.
6. Click **Done**.


---

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