> ## Documentation Index
> Fetch the complete documentation index at: https://docs.heysonara.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Configuring the Language Model

> Choose the AI model that powers your agent's intelligence.

## Language model settings

The language model (LLM) is the brain of your agent. It determines how well your agent understands context, follows instructions, and generates responses.

## Choosing a provider and model

Navigate to the **LLM** tab in your agent's configuration to select:

### Providers

| Provider      | Models                      | Best for                                          |
| ------------- | --------------------------- | ------------------------------------------------- |
| **OpenAI**    | GPT-4o, GPT-4o-mini         | General purpose, strong instruction following     |
| **Anthropic** | Claude Sonnet, Claude Haiku | Nuanced conversations, safety-conscious responses |
| **Google**    | Gemini models               | Multi-modal capabilities                          |

### Selecting a model

Choose a model based on your needs:

* **Higher capability models** (GPT-4o, Claude Sonnet)  - Better at complex reasoning, nuanced conversations, and following detailed instructions. Slightly higher latency.
* **Faster models** (GPT-4o-mini, Claude Haiku)  - Lower latency and cost, good for simpler use cases.

## Model parameters

Fine-tune your model's behavior with these parameters:

### Temperature

Controls randomness in responses.

* **0.0**  - Deterministic, always gives the most likely response
* **0.5**  - Balanced (recommended for most use cases)
* **1.0**  - More creative and varied responses

### Max tokens

The maximum length of the model's response. Higher values allow longer responses but may increase latency.

### Top P

Controls diversity of word choices. Lower values make responses more focused; higher values make them more diverse. Default is **1.0**.

### Frequency penalty

Reduces repetition of specific words. Values from **0.0** (no penalty) to **2.0** (strong penalty). Default is **0.0**.

### Presence penalty

Encourages the model to talk about new topics. Values from **0.0** (no penalty) to **2.0** (strong penalty). Default is **0.0**.

<Tip>
  For most voice agents, start with the default parameters. Only adjust if you notice specific issues like repetitive responses or responses that are too long.
</Tip>