# Configure Agent Behavior
URL: /guides/setup-project/agent-behavior

This guide shows how to use custom instructions to define your agent's personality, expertise, and behavioral guidelines.

For an overview of how custom instructions fit into the configuration system, see [Agent Configuration](/concepts/agent-configuration).

## Configuring Custom Instructions

To set custom instructions for your project:

1. Open your project in the [Tambo Cloud dashboard](https://console.tambo.co)
2. Navigate to **Settings**
3. Find the **Custom Instructions** field
4. Enter your instructions
5. Click **Save**

Changes apply to all new messages sent to the project.

## Writing Effective Custom Instructions

### Keep It Focused

Custom instructions should define static behavior that applies to all users add guidelines that:

* Define the agent's role and expertise
* Set tone and personality
* Establish behavioral guidelines
* Specify response format preferences

### Structure Your Instructions

A clear structure helps the model understand and follow your instructions:

```
You are a [role/identity]. [Brief description of purpose].

When responding:
- [Key guideline 1]
- [Key guideline 2]
- [Key guideline 3]

[Any specific behaviors or constraints]
```

## Practical Examples

### Example 1: General-Purpose Assistant

**Use case:** A helpful assistant that answers questions across many topics.

**Custom instructions:**

```
You are a knowledgeable and helpful assistant. Provide clear, accurate
answers to questions. When you're unsure, say so rather than guessing.
Keep responses concise but complete.
```

### Example 2: Specialized Domain Expert

**Use case:** An agent focused on a specific domain (e.g., legal, medical, technical).

**Custom instructions:**

```
You are a senior software engineer specializing in React and TypeScript.
When helping with code:
- Write type-safe TypeScript with proper interfaces
- Follow React best practices and hooks patterns
- Explain your reasoning for architectural decisions
- Point out potential bugs or security issues
- Suggest improvements when appropriate
```

### Example 3: Customer Support Agent

**Use case:** Handling customer inquiries professionally and efficiently.

**Custom instructions:**

```
You are a friendly customer support agent for [Company Name]. Your goal
is to resolve customer issues efficiently and professionally.

Always:
- Greet customers warmly
- Listen carefully to their concerns
- Provide accurate, specific solutions
- Escalate to human support when needed
- Thank customers for their patience

Maintain a professional, empathetic tone even when customers are frustrated.
```

## Testing Your Instructions

After setting custom instructions:

1. Send a test message that should trigger your guidelines
2. Verify the agent follows the specified behavior
3. Test edge cases to ensure appropriate responses
4. Adjust and iterate based on results

For parameter tuning to control response creativity and consistency, see [Configure LLM Provider](/guides/setup-project/llm-provider).

## Next Steps

* [Configure LLM Provider](/guides/setup-project/llm-provider) - Model selection and parameter tuning
* [Give Tambo Extra Context](/guides/give-context) - Runtime context injection for user-specific information
* [Agent Configuration Concepts](/concepts/agent-configuration) - Understanding the configuration system
* [Additional Context](/concepts/additional-context) - Thread and message-level context patterns