Vapi Voice AI MCP server

The Vapi MCP server integrates Vapi's voice AI capabilities with Cursor, allowing you to make outbound voice calls, manage voice assistants, and retrieve conversation details directly from your Cursor environment.

Installation

Environment Configuration

Create a .env file in the vapi-mcp-server directory with the following variables:

# Vapi API Keys
VAPI_ORG_ID=your-org-id
VAPI_PRIVATE_KEY=your-private-key
VAPI_KNOWLEDGE_ID=your-knowledge-id
VAPI_JWT_PRIVATE=your-jwt-private

# Environment
NODE_ENV=development

Building the Server

To build the server:

cd vapi-mcp/vapi-mcp-server
npm install
npm run build

Configuration in Cursor

Setting Up MCP in Cursor

To configure the Vapi MCP server in Cursor, you need to create a .cursor/mcp.json file with the following configuration:

"Vapi Voice AI Tools": {
  "command": "node",
  "type": "stdio",
  "args": [
    "/path/to/vapi-mcp/vapi-mcp-server/dist/index.js"
  ],
  "cwd": "/path/to/vapi-mcp/vapi-mcp-server",
  "env": {
    "VAPI_ORG_ID": "your-org-id",
    "VAPI_PRIVATE_KEY": "your-private-key",
    "VAPI_KNOWLEDGE_ID": "your-knowledge-id",
    "VAPI_JWT_PRIVATE": "your-jwt-private",
    "NODE_ENV": "development"
  }
}

Important notes:

• Replace /path/to/ with the actual absolute path on your system
• Make sure to include your actual API keys in the environment variables
• The cwd parameter is required to ensure the server runs in the correct directory
• All environment variables must be explicitly provided in the configuration

Using the Server

Once configured, you can use the following tools in Cursor:

Available Tools

1. vapi_call

   • Make outbound calls using Vapi's voice AI

2. vapi_assistant

   • Manage voice assistants (create, get, list, update, delete)

3. vapi_conversation

   • Retrieve conversation details from previous calls

Troubleshooting

Fixing "Client Closed" Error

If you see "Client Closed" in the Cursor MCP Tools panel:

1. Check Working Directory

   • Ensure the cwd parameter is set correctly in your mcp.json

2. Verify Environment Variables

   • Make sure all required environment variables are passed in the configuration

3. Check Module Type

   • Ensure package.json has "type": "module"

4. Test Server Directly

   • Run the server manually to check for errors:

   cd vapi-mcp/vapi-mcp-server
   node --trace-warnings dist/index.js
   

Resolving Module Not Found Errors

If you get "Error: Cannot find module" when running:

1. Check Working Directory

   • Make sure you're running from the correct directory

2. Rebuild the Project

   npm run build
   

3. Reinstall Dependencies

   npm install
   

How to add this MCP server to Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > MCP and click "Add new global MCP server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "cursor-rules-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "cursor-rules-mcp"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explictly ask the agent to use the tool by mentioning the tool name and describing what the function does.