Zero MCP Server

An MCP (Model Context Protocol) server for integrating Zero CRM with Claude Desktop and other MCP-compatible clients.

Features

• 16 tools for full CRUD operations on companies, contacts, and deals
• Single workspace mode - automatically caches workspace ID
• Smart filtering - use JSON where clauses for powerful queries
• Pagination - built-in limit/offset support
• Formatted output - Markdown responses for readability

Installation

npm install
npm run build

Configuration

Claude Desktop

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

{
  "mcpServers": {
    "zero": {
      "command": "node",
      "args": ["/path/to/zero-api/dist/index.js"],
      "env": {
        "ZERO_API_KEY": "your-api-key-here",
        "ZERO_WORKSPACE_NAME": "My Workspace"
      }
    }
  }
}

Replace /path/to/zero-api with the actual path and add your Zero API key.

Environment Variables

Variable	Required	Description
ZERO_API_KEY	Yes	Your Zero API key
ZERO_WORKSPACE_NAME	No	Workspace name to use (defaults to first workspace)

Getting Your Zero API Key

Request an API key from the Zero team. Self-service API key generation is not yet available.

Available Tools

Workspace

• zero_get_workspace - Get and cache the default workspace

Companies

• zero_list_companies - List/search companies with filtering
• zero_get_company - Get company by ID
• zero_create_company - Create a new company
• zero_update_company - Update company fields
• zero_delete_company - Archive or delete a company

Contacts

• zero_list_contacts - List/search contacts with filtering
• zero_get_contact - Get contact by ID
• zero_create_contact - Create a new contact
• zero_update_contact - Update contact fields
• zero_delete_contact - Archive or delete a contact

Deals

• zero_list_deals - List/search deals with filtering
• zero_get_deal - Get deal by ID
• zero_create_deal - Create a new deal
• zero_update_deal - Update deal fields
• zero_delete_deal - Archive or delete a deal

Usage Examples

Once configured, you can ask Claude:

• "What workspace am I connected to?"
• "List all my companies"
• "Show deals over $50k in negotiation"
• "Create a contact for Acme Corp"
• "Update deal X to stage 'closed won'"

Filtering

Tools support JSON where clauses with MongoDB-style $-prefixed operators:

{"name": {"$contains": "Acme"}}
{"value": {"$gte": 50000}}
{"value": {"$between": [1000, 5000]}}
{"stage": {"$in": ["stage-id-1", "stage-id-2"]}}
{"closeDate:month": "2026-01"}
{"ownerIds": {"$includes": "user-id"}}
{"location.city": "San Francisco"}

Development

npm run dev    # Watch mode
npm run build  # Build for production

API Reference

This server integrates with Zero's REST API. See src/api-reference.ts for documented endpoints.

Note: Zero is in beta. When they update their API, update this MCP accordingly.

License

MIT