arca-mcp

Arca MCP Server

Model Context Protocol (MCP) server for the Arca API. Enables Claude Desktop and other MCP-compatible LLMs to interact with your Arca workspaces, tasks, lists, folders, and comments.

Features

• Workspaces: List and get workspace details
• Tasks: List, create, update, delete, and get task details
• Lists: List, create, update, and delete lists
• Folders: List, create, update, and delete folders
• Comments: List and create comments on tasks
• Statuses: List, create, update, and delete workspace statuses
• Labels: List, create, update, and delete workspace labels

All operations use your personal Arca API key to authenticate directly with the Arca API.

Installation

Quick Setup (Recommended)

Add this to your claude_desktop_config.json:

{
  "mcpServers": {
    "arca": {
      "command": "npx",
      "args": ["-y", "arca-mcp"],
      "env": {
        "ARCA_API_KEY": "arca_your_api_key_here"
      }
    }
  }
}

Get your API key from Settings → API Keys in the Arca app.

Config file locations:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

Then restart Claude Desktop to connect.

Build from Source

If you prefer to build locally:

git clone https://github.com/gredevelopment/arca-mcp.git
cd arca-mcp
npm install
npm run build

Update your Claude Desktop config to use the local build:

{
  "mcpServers": {
    "arca": {
      "command": "node",
      "args": ["/absolute/path/to/arca-mcp/build/index.js"],
      "env": {
        "ARCA_API_KEY": "arca_your_api_key_here"
      }
    }
  }
}

Usage

Once connected, you can ask Claude to interact with your Arca workspace:

• "List all my Arca workspaces"
• "Show me tasks in the [workspace name] workspace"
• "Create a task called 'Review PR' in the Development list"
• "Update task #42 to high priority"
• "Add a comment to task #42: 'Looks good to merge'"

Available Tools

Workspaces

• list_workspaces - List all workspaces you have access to
• get_workspace - Get detailed information about a specific workspace

Tasks

• list_tasks - List tasks in a workspace (optionally filtered by list)
• get_task - Get detailed information about a task
• create_task - Create a new task
• update_task - Update task properties (title, description, status, priority, dates)
• delete_task - Delete a task

Lists

• list_lists - List all lists in a workspace (optionally filtered by folder)
• create_list - Create a new list
• update_list - Update list properties
• delete_list - Delete a list

Folders

• list_folders - List all folders in a workspace
• create_folder - Create a new folder
• update_folder - Update folder properties
• delete_folder - Delete a folder

Comments

• list_comments - List all comments on a task
• create_comment - Add a comment to a task

Statuses

• list_statuses - List all statuses in a workspace
• create_status - Create a new status (owner/admin only)
• update_status - Update status properties (owner/admin only)
• delete_status - Delete a status, optionally reassigning tasks (owner/admin only)

Labels

• list_labels - List all labels in a workspace
• create_label - Create a new label
• update_label - Update label properties (owner/admin only)
• delete_label - Delete a label (owner/admin only)

How It Works

• The MCP server runs locally on your machine via npx
• It authenticates to the Arca API using your personal API key
• Claude Desktop communicates with the server via STDIO (standard input/output)
• All data stays between your machine and Arca's API - no third-party servers involved

Smart Tool Chaining

The server includes built-in instructions that guide LLMs to make intelligent multi-step decisions. For example:

Instead of saying: "I can't list tasks by workspace name, only by ID"

The LLM will automatically:

• Call list_workspaces to find the workspace ID from the name
• Use that ID to call list_tasks
• Return the results seamlessly

This works for common patterns like:

• "Show tasks in My Project workspace" → Resolves workspace name to ID automatically
• "Create a task in Development workspace" → Finds workspace, optionally suggests statuses
• "Update the 'Fix bug' task" → Searches for task by title, then updates it

The server instructions are registered as an MCP prompt (server_instructions) that LLMs can reference, plus enhanced tool descriptions that encourage smart workflow patterns.

Requirements

• Node.js 16 or higher
• An Arca account with API access
• Claude Desktop (or another MCP-compatible client)

Security

Your API key is stored locally in the Claude Desktop config and never leaves your machine except to authenticate with the official Arca API (https://api.getarca.app).

Support

For issues or questions:

• GitHub Issues: https://github.com/gredevelopment/arca-mcp/issues
• Arca Support: https://getarca.app/support

License

ISC License - see LICENSE file for details.