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

# Documentation

> Read HAL and platform documentation from within your agent

# Documentation

Read internal Herd documentation by document ID. Supports fetching multiple documents in a single call.

## Returns

* **Document content** — Full text of the requested documentation
* **Available IDs** — If an unknown ID is provided, returns the list of available document IDs

## Example Queries

```
Show me the HAL syntax documentation
```

```
Read the HAL examples and module docs
```

## Parameters

| Parameter    | Required | Description                                              |
| ------------ | -------- | -------------------------------------------------------- |
| `documentId` | Yes      | A single document ID string, or an array of document IDs |

### Available Documents

| Document ID               | Content                                                |
| ------------------------- | ------------------------------------------------------ |
| `hal://spec/syntax`       | HAL grammar and special forms                          |
| `hal://spec/modules/herd` | Blockchain functions (read, write, encode, swap, etc.) |
| `hal://spec/examples`     | Worked HAL expression examples                         |

## Tips

<Tip>
  Fetch all three HAL docs at once by passing an array: `["hal://spec/syntax", "hal://spec/modules/herd", "hal://spec/examples"]`
</Tip>

<Tip>
  Always read the HAL documentation before creating or editing HAL expressions — the syntax has non-obvious requirements.
</Tip>

## Related Tools

* **Create actions** → [Actions & Adapters](/herd-mcp/tools/hal-actions-adapters)
* **Test expressions** → [Evaluation](/herd-mcp/tools/hal-evaluation)
* **HAL language reference** → [HAL Expression System](/herd-actions/overview)

## Next Steps

<CardGroup cols={2}>
  <Card title="HAL Reference" icon="book" href="/herd-actions/overview">
    Full HAL language documentation
  </Card>

  <Card title="Evaluation" icon="flask" href="/herd-mcp/tools/hal-evaluation">
    Simulate HAL expressions
  </Card>
</CardGroup>