opencode-matrix-plugin

OpenCode V2 plugin that connects your OpenCode agent to Matrix messaging servers.

Features

• Matrix Bot Integration: Connect OpenCode to any Matrix homeserver
• Thread Isolation: Each Matrix thread gets its own isolated session
• E2EE Support: End-to-end encryption via Rust crypto SDK
• Auto-join: Bot auto-joins rooms it's invited to
• Configurable Triggers: triggerPatterns array — empty = all messages, configured = only trigger/mention/thread-reply
• Thread Replies: Respond to plain replies within active threads (follow-up mode)
• Bridge Commands: /status, /clear, /help for session management
• Rate Limiting: Configurable per-user rate limiting
• User Allowlisting: Restrict who can interact with the bot
• Session Persistence: Sessions survive plugin reloads via ~/.opencode-matrix-sessions.json

Installation

Option 1: Local Plugin (Recommended)

1. Create a symlink from your OpenCode config to this plugin:

mkdir -p ~/.config/opencode/plugins
ln -s /path/to/your/opencode_matrix ~/.config/opencode/plugins/matrix-plugin

2. Add the plugin to your opencode.jsonc:

{
  "plugins": [
    "./plugins/matrix-plugin"
  ]
}

Option 2: Published Package

{
  "plugins": [
    "opencode-matrix-plugin"
  ]
}

Configuration

Конфигурация загружается в следующем порядке приоритетов:

1. Plugin options из opencode.jsonc (plugins[].options) — высший приоритет
2. Config file — .opencode/matrix.json (проект) или ~/.config/opencode/matrix.json (глобальный)
3. Environment variables — MATRIX_* — базовый уровень

Auto-create: Если конфиг не найден ни в одной директории, плагин автоматически создаст ~/.config/opencode/matrix.json с дефолтными значениями (права 0o600).

Config File

Создайте matrix.json в одной из директорий:

Проектный уровень — .opencode/matrix.json (рядом с opencode.jsonc):

{
  "homeserver": "https://matrix.org",
  "userId": "@opencode-bot:matrix.org",
  "password": "your-bot-password",
  "autoJoin": true,
  "triggerPatterns": ["!oc ", "!ai "],
  "allowedUsers": ["@alice:matrix.org"],
  "threadIsolation": true,
  "respondToThreadReplies": true,
  "rateLimitSeconds": 5,
  "botName": "opencode",
  "enabled": true
}

Глобальный уровень — ~/.config/opencode/matrix.json:

{
  "homeserver": "https://matrix.org",
  "userId": "@opencode-bot:matrix.org",
  "password": "your-bot-password",
  "triggerPatterns": ["!oc "],
  "threadIsolation": true,
  "enabled": true
}

Файлы поддерживают JSONC (комментарии //).

Environment Variables

Variable	Description	Default
MATRIX_HOMESERVER	Matrix server URL	https://matrix.org
MATRIX_USER_ID	Bot user ID	(required)
MATRIX_ACCESS_TOKEN	Static access token	(optional)
MATRIX_PASSWORD	Bot password for login	(optional, preferred)
MATRIX_STORAGE_PATH	Override storage directory	~/.local/share/opencode-matrix-bot
MATRIX_TRIGGER	Override trigger pattern	—
MATRIX_ALLOWED_USERS	Comma-separated user IDs	—

All Options

Option	Type	Default	Description
homeserver	string	https://matrix.org	Matrix homeserver URL
userId	string	-	Bot user ID (e.g., @bot:server.org)
accessToken	string	-	Static access token (or use password)
password	string	-	Bot password (preferred, auto-refreshes token)
deviceId	string	opencode-matrix-plugin	Device ID for login
autoJoin	boolean	true	Auto-join rooms the bot is invited to
triggerPatterns	string[]	[]	Message prefixes to trigger the bot. Empty = all messages.
ignoreRooms	string[]	[]	Room IDs to completely ignore
ignoreUsers	string[]	[]	User IDs to completely ignore
allowedUsers	string[]	[]	Allowlist (empty = everyone)
formatHtml	boolean	false	Send HTML-formatted responses
threadIsolation	boolean	true	Per-thread sessions
respondToThreadReplies	boolean	true	Reply to plain thread messages (follow-up)
rateLimitSeconds	number	5	Per-user cooldown between messages
botName	string	opencode	Bot display name for @mentions
storagePath	string	auto	Directory for bot state and crypto keys
enabled	boolean	true	Enable/disable the plugin

Config Priority

Configuration is loaded in this order (highest priority first):

1. Plugin options from opencode.jsonc (plugins[].options)
2. Config file — matrix.json or matrix.jsonc in:
   • Project level: .opencode/matrix.json (next to opencode.jsonc)
   • Global level: ~/.config/opencode/matrix.json
3. Environment variables — MATRIX_*

Auto-create: If no config is found, the plugin auto-creates ~/.config/opencode/matrix.json with defaults (permissions 0o600).

Example Config

Copy matrix.json.example from the project root and customize:

cp matrix.json.example ~/.config/opencode/matrix.json

See the example file for fully commented configuration with all options.

Usage

Triggering the Bot

Behavior depends on triggerPatterns config:

With triggers configured (e.g., ["!oc "]):

1. Prefix trigger: Send !oc What is TypeScript?
2. @Mention: Send @opencode What is TypeScript?
3. Thread reply: Reply to any message in an active thread (follow-up mode)

With empty triggers (triggerPatterns: []):

• All messages are processed

Bridge Commands

Command	Description
/help or /h	Show help message
/status	Show current session info
/clear or /reset	Clear current session

Room Setup

1. Invite @opencode:matrix.org to your room
2. The bot auto-joins (if autoJoin: true)
3. Start messaging with the trigger prefix or @mention

Bot Setup (First Time)

1. Create a Matrix account for your bot (or use existing)
2. Set MATRIX_PASSWORD or MATRIX_ACCESS_TOKEN
3. The bot will auto-login and save the access token
4. Invite the bot to your rooms

Architecture

Matrix Room
    │
    ▼
MatrixBotClient (matrix-bot-sdk + Rust crypto)
    │
    ├── Event: room.message
    ├── Authentication: password / token
    ├── E2EE: automatic
    └── Thread handling: m.relates_to
    │
    ▼
SessionManager
    │
    ├── Rate limiting
    ├── Thread isolation (room:threadId)
    └── Session persistence (~/.opencode-matrix-sessions.json)
    │
    ▼
OpenCode V2 API
    │
    ├── ctx.session.prompt() / ctx.session.create()
    └── Session mapping: Matrix thread → OpenCode session
    │
    ▼
Response → MatrixBotClient → Matrix Room

Session Management

Sessions are persisted across plugin restarts in ~/.opencode-matrix-sessions.json.

• V2 API: Sessions are created with deterministic IDs (roomId:threadRootId)
• Sync: Use sessionManager.syncWithOpenCode(sessionIds) to prune orphaned sessions

Security

• E2EE: Full end-to-end encryption support via @matrix-org/matrix-sdk-crypto-nodejs
• Token Storage: Access tokens saved with 0o600 permissions
• User Allowlisting: Restrict bot access to specific users
• Rate Limiting: Prevent message spam
• Mutex Lock: Prevents duplicate bot startup (server + client both load plugins)

Troubleshooting

Bot doesn't respond

1. Check that the bot is in the room
2. Verify the trigger pattern matches your message
3. Check if the user is in the allowed list (if configured)
4. Check ~/.local/share/opencode-matrix-bot/ for state files
5. Check logs: ~/.opencode-matrix-plugin/plugin.log

Authentication fails

1. Verify MATRIX_USER_ID and MATRIX_PASSWORD are correct
2. Check that the bot account exists on the homeserver
3. Try setting MATRIX_ACCESS_TOKEN directly
4. Check homeserver logs for authentication errors

E2EE issues

1. Ensure @matrix-org/matrix-sdk-crypto-nodejs is installed
2. Check crypto storage directory has write permissions
3. Verify the bot has access to the encrypted room

Double bot startup

OpenCode V2 loads plugins in both the background server and the client. The plugin uses a file-based mutex (~/.local/share/opencode-matrix-bot/plugin-data/lock) to prevent duplicate bot instances. If you see two bots, check that the lock file is being created.

Development

cd /path/to/opencode_matrix
bun install
bun run typecheck
bun run build

License

MIT