Developer Guide

Set up and run Context7 MCP locally for development

This guide covers how to set up the Context7 MCP server locally for development and testing.

Getting Started

Clone the project and install dependencies:

git clone https://github.com/upstash/context7.git
cd context7
pnpm i

Build:

pnpm run build

Run the server:

node packages/mcp/dist/index.js

CLI Arguments

context7-mcp accepts the following CLI flags:

Flag	Description	Default
--transport <stdio|http>	Transport to use. Use http for remote HTTP server or stdio for local integration.	stdio
--port <number>	Port to listen on when using http transport.	3000
--api-key <key>	API key for authentication (or set CONTEXT7_API_KEY env var).	-

Get your API key by creating an account at context7.com/dashboard.

Examples

HTTP transport on port 8080:

node packages/mcp/dist/index.js --transport http --port 8080

Stdio transport with API key:

node packages/mcp/dist/index.js --transport stdio --api-key YOUR_API_KEY

Environment Variables

You can use the CONTEXT7_API_KEY environment variable instead of passing the --api-key flag. This is useful for:

• Storing API keys securely in .env files
• Integration with MCP server setups that use dotenv
• Tools that prefer environment variable configuration

The --api-key CLI flag takes precedence over the environment variable when both are provided.

Using .env File

# .env
CONTEXT7_API_KEY=your_api_key_here
CONTEXT7_API_URL=https://context7.com/api

CONTEXT7_API_URL sets the base URL for Context7 API calls and defaults to https://context7.com/api. Override it for self-hosted deployments or proxies that sit in front of the API.

MCP Configuration with Environment Variable

{
  "mcpServers": {
    "context7": {
      "command": "npx",
      "args": ["-y", "@upstash/context7-mcp"],
      "env": {
        "CONTEXT7_API_KEY": "YOUR_API_KEY"
      }
    }
  }
}

Local Development Configuration

When developing locally, use this configuration to run from source:

{
  "mcpServers": {
    "context7": {
      "command": "npx",
      "args": ["tsx", "/path/to/folder/context7/packages/mcp/src/index.ts", "--api-key", "YOUR_API_KEY"]
    }
  }
}

Testing with MCP Inspector

Test your setup using the MCP Inspector:

npx -y @modelcontextprotocol/inspector npx @upstash/context7-mcp

This opens an interactive inspector to verify Context7 tools are working correctly.