cowork-code-mcp-server

An MCP server that acts as a real-time bridge for communication and task delegation between Claude Code and Claude Cowork agents.

What it does

Two Claude agents — one running as "code" and the other as "cowork" — can exchange messages and coordinate tasks through a shared SQLite database. Each server instance runs with an identity (code or cowork) and exposes MCP tools scoped to that identity.

Architecture

Claude Code                          Claude Cowork
    |                                      |
    | stdio (JSON-RPC)                     | stdio (JSON-RPC)
    v                                      v
CoworkBridge                         CoworkBridge
(identity: "code")                   (identity: "cowork")
    |                                      |
    +----------> SQLite DB <---------------+
                ~/.cowork-code-mcp/messages.db

Both instances share the same SQLite database. Messages sent by one agent are read by the other. Tasks created by one are picked up and updated by the other.

MCP Tools

Tool	Description
send_message	Send a message to the other agent (params: to, content)
read_messages	Retrieve unread messages for current identity (params: mark_read)
create_task	Create a task for the other agent (params: to, title, description)
get_tasks	Get tasks assigned to current identity (params: status filter)
update_task	Update a task's status and result (params: task_id, status, result)

Task statuses: pending -> in_progress -> completed | failed

Installation

Prerequisites

• Rust (stable toolchain)

Build and install

git clone https://github.com/jagwar/cowork-code-mcp-server.git
cd cowork-code-mcp-server
cargo build --release

The binary is at ./target/release/cowork-code-mcp-server. The SQLite database is created automatically at ~/.cowork-code-mcp/messages.db on first run.

Configure for Claude Code

Add to ~/.claude/settings.json:

{
  "mcpServers": {
    "cowork-bridge": {
      "command": "/absolute/path/to/cowork-code-mcp-server/target/release/cowork-code-mcp-server",
      "args": ["code"]
    }
  }
}

Configure for Claude Desktop (Cowork)

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "cowork-bridge": {
      "command": "/absolute/path/to/cowork-code-mcp-server/target/release/cowork-code-mcp-server",
      "args": ["cowork"]
    }
  }
}

The CLI argument sets the identity — use code or cowork (defaults to code). Both instances must point to the same binary so they share the same database.

Direct DB access (CLI)

You can also interact with the bridge directly via SQLite, useful for scripting or manual testing.

Send a message

sqlite3 ~/.cowork-code-mcp/messages.db \
  "INSERT INTO messages (id, sender, recipient, content, read, created_at) \
   VALUES ('$(uuidgen)', 'code', 'cowork', 'Your message here', 0, datetime('now'));"

Create a task

sqlite3 ~/.cowork-code-mcp/messages.db \
  "INSERT INTO tasks (id, sender, recipient, title, description, status, created_at) \
   VALUES ('$(uuidgen)', 'code', 'cowork', 'Task title', 'Task description', 'pending', datetime('now'));"

Check for unread messages and pending tasks

sqlite3 -header -column ~/.cowork-code-mcp/messages.db \
  "SELECT id, sender, content, created_at FROM messages WHERE read=0 AND recipient='code';"
sqlite3 -header -column ~/.cowork-code-mcp/messages.db \
  "SELECT id, sender, title, description, created_at FROM tasks WHERE recipient='code' AND status='pending';"

Swap 'code' and 'cowork' to target the other direction. You can batch multiple INSERTs — the recipient picks them up on next poll.

Project structure

src/
  main.rs   # MCP server, tool handlers, and stdio transport
  db.rs     # SQLite database layer (messages + tasks tables)

Dependencies

• rmcp — MCP protocol implementation (server, macros, stdio transport)
• tokio — Async runtime
• rusqlite — SQLite with bundled library
• serde/serde_json — JSON serialization
• uuid — UUID v4 generation for message/task IDs
• chrono — Timestamps (RFC 3339)
• schemars — JSON Schema generation for tool parameters
• anyhow — Error handling

License

MIT — see LICENSE.