Developer Guide - Context7 MCP

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.gitcd context7pnpm 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).	-

Note

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

Warning

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

Using .env File#

# .envCONTEXT7_API_KEY=your_api_key_here

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.