# Mattermost Plugin

## Overview

OpenClaw integrates with Mattermost, a self-hostable team messaging platform, via a plugin.

## Installation

The plugin requires separate installation:

```bash
openclaw plugins install @openclaw/mattermost
```

## Core Configuration

The minimal setup requires three elements:

- A bot token
- Base URL
- A DM policy

Mattermost responds to DMs automatically, with channel interactions governed by the `chatmode` setting.

## Chat Modes

Three response patterns are available:

- **oncall** (default): responds only to @mentions
- **onmessage**: replies to all channel messages
- **onchar**: triggers on specific prefix characters like `>` or `!`

## Access Controls

### DM Security

Uses a pairing code system by default, allowing administrators to approve unknown senders.

### Channel Access

Controlled via allowlists using the `groupAllowPolicy` setting.

## Multi-Account Support

Multiple Mattermost instances can be configured simultaneously under separate account identifiers, each with independent tokens and base URLs.

## Message Delivery Targets

Outbound messages use standardized formats:

- `channel:<id>` - Channel messages
- `user:<id>` - Direct messages by user ID
- `@username` - Direct messages by username

## Environment Variables

Environment variable alternatives are available for the default account configuration.

## Troubleshooting

Common issues involve:

- Channel visibility
- Authentication issues