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

# How to Customize Agent Mode

> Learn how to customize Agent Mode in Gobi to better fit your workflow and coding style.

## How to Add Rules Blocks

Adding Rules can be done in your configuration locally or in the Hub. You can explore Rules on the Gobi Hub and refer to the [Rules deep dive](/customize/deep-dives/rules) for more details.

## How to Customize System Messages

You can customize the system messages for Chat, Agent, and Plan modes using model-level configuration:

```yaml theme={null}
models:
  - name: GPT-4o
    provider: openai
    model: gpt-4o
    chatOptions:
      baseSystemMessage: "You are a helpful coding agent."
      baseAgentSystemMessage: "You are a systematic coding agent. Break down problems methodically."
      basePlanSystemMessage: "You are a planning agent. Create clear, actionable steps."
```

## How to Add MCP Tools

You can add MCP servers to your configuration to give Agent mode access to more tools. Explore [MCP Servers on the Hub](https://hub.gourmand.dev) and consult the [MCP guide](/customize/deep-dives/mcp) for more details.

## How to Configure Tool Policies

You can adjust the Agent mode's tool usage behavior to three options:

* **Ask First (default)**: Request user permission with "Cancel" and "Gobi" buttons
* **Automatic**: Automatically call the tool without requesting permission
* **Excluded**: Do not send the tool to the model

:::warning
Be careful setting tools to "automatic" if their behavior is not read-only.
:::

To manage tool policies:

1. Click the tools icon in the input toolbar
2. View and change policies by clicking on the policy text
3. You can also toggle groups of tools on/off

Tool policies are stored locally per user.