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

# Using Templates

> Start with pre-built agent templates

# Using Templates

Templates give you a working agent in seconds. Start from a proven foundation, then customize.

## Available Templates

| Template         | Description                       | Best For                      |
| ---------------- | --------------------------------- | ----------------------------- |
| `default`        | Coding agent with file/bash tools | General purpose, coding tasks |
| `research-agent` | Web search and document synthesis | Research, reports, analysis   |
| `support-agent`  | Ticket handling and escalation    | Customer support workflows    |
| `mcp-tools`      | Custom tool integration example   | Learning MCP patterns         |

## Using cast init

```bash theme={null}
cast init my-agent
```

Interactive prompt:

```
? Select a template:
❯ default — Coding agent with file and bash tools (like Claude Code)
  research-agent — Deep research with web search and document synthesis
  support-agent — Customer support with ticket handling and escalation
  mcp-tools — Agent with example MCP server integration
```

### Skip the prompt

```bash theme={null}
cast init my-agent --template research-agent
```

## Template Structure

Every template includes:

```
my-agent/
├── castari.json      # Agent configuration
├── package.json      # Dependencies
├── tsconfig.json     # TypeScript config
├── src/
│   └── index.ts      # Agent entry point with tools
├── CLAUDE.md         # Agent instructions
└── README.md         # Documentation
```

***

## Template: default

A Claude Code-style agent with file and bash tools.

**Tools included:**

| Tool         | Description             |
| ------------ | ----------------------- |
| `read_file`  | Read file contents      |
| `write_file` | Create/update files     |
| `bash`       | Execute shell commands  |
| `list_files` | List directory contents |

**Example invocations:**

```bash theme={null}
cast invoke my-agent "What files are here?"
cast invoke my-agent "Create a hello.py that prints Hello World"
cast invoke my-agent "Run the tests"
```

**Best for:** General-purpose coding assistance, file manipulation, automation.

***

## Template: research-agent

Deep research with web search and document synthesis.

**Tools included:**

| Tool          | Description              |
| ------------- | ------------------------ |
| `web_search`  | Search the web           |
| `read_url`    | Fetch and read web pages |
| `save_report` | Save findings to file    |
| `read_file`   | Read local documents     |

**Example invocations:**

```bash theme={null}
cast invoke my-agent "Research the current state of AI agents in 2026"
cast invoke my-agent "Compare AWS, GCP, and Azure for serverless"
```

<Note>
  The research-agent template includes a mock web search. For production, integrate with SerpAPI, Tavily, or similar.
</Note>

**Best for:** Research tasks, report generation, competitive analysis.

***

## Template: support-agent

Customer support with ticket handling.

**Tools included:**

| Tool            | Description           |
| --------------- | --------------------- |
| `lookup_user`   | Find user by email/ID |
| `lookup_order`  | Find order details    |
| `create_ticket` | Escalate to human     |
| `send_response` | Reply to customer     |

**Example invocations:**

```bash theme={null}
cast invoke my-agent "I need help with order #12345"
cast invoke my-agent "How do I reset my password?"
```

**Best for:** Customer support automation, help desk, FAQ handling.

***

## Template: mcp-tools

Example of custom MCP tool integration.

**Tools included:**

| Tool                | Description             |
| ------------------- | ----------------------- |
| `calculate`         | Math calculations       |
| `get_weather`       | Weather lookup (mock)   |
| `query_database`    | Database queries (mock) |
| `send_notification` | Send alerts             |

**Use this to learn:**

* How to define tool schemas
* How to implement tool handlers
* How to integrate external services

**Best for:** Learning tool development, prototyping custom integrations.

***

## Customizing Templates

### 1. Edit CLAUDE.md

The `CLAUDE.md` file contains agent instructions:

```markdown theme={null}
# My Agent

You are a helpful assistant that...

## Guidelines
- Be concise
- Always explain before acting
- Ask for clarification when unsure
```

### 2. Modify Tools

Edit `src/index.ts` to add, remove, or modify tools:

```typescript theme={null}
const tools: Anthropic.Tool[] = [
  {
    name: "my_custom_tool",
    description: "Does something useful",
    input_schema: {
      type: "object",
      properties: {
        input: { type: "string" }
      },
      required: ["input"]
    }
  }
];
```

### 3. Add Dependencies

```bash theme={null}
npm install axios  # Example: add HTTP client
```

Then use in your agent:

```typescript theme={null}
import axios from 'axios';

// In your tool handler
const response = await axios.get('https://api.example.com/data');
```

### 4. Redeploy

After changes:

```bash theme={null}
cast deploy
```

## See Also

<CardGroup cols={2}>
  <Card title="Custom Agents" icon="pen" href="/guides/custom-agents">
    Build from scratch
  </Card>

  <Card title="MCP Integration" icon="plug" href="/guides/mcp">
    Advanced tool patterns
  </Card>
</CardGroup>