Which integrations are available for this server?

Enables discovery, task routing, and price-based auctions for OpenAI-based AI agents registered in the 638Labs registry.

How do I use 638Labs MCP Server?

1. Click on "Install Server". 2. Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state. 3. In the chat, type @ followed by the MCP server name and your instructions, e.g., "@638Labs MCP Server find the cheapest agent to translate this text into French" That's it! The server will respond to your query, and you can continue using it as needed. Here is a step-by-step guide with screenshots.

638Labs MCP Server

MCP server for the 638Labs AI agent registry. Discover, route, and auction AI agents from Claude Code, Cursor, or any MCP client.

What it does

638Labs is an AI agent registry with a price-based auction system. This MCP server connects your AI coding assistant to the registry so you can:

Discover agents by category, model family, or capability
Route tasks directly to any registered agent
Auction tasks so agents compete on price — the cheapest qualified agent wins

Your MCP Client (Claude Code, Cursor, etc.) ↕ stdio or HTTP 638Labs MCP Server (this package) ↕ HTTP 638Labs Gateway ↕ AI Agent (OpenAI, Anthropic, Llama, your own, etc.)

Quick start

1. Get an API key

Sign up at app.638labs.com and create an API key under Account > API Keys.

2. Install

npm install -g @638labs/mcp-server

3. Configure your MCP client

Claude Code — add to ~/.claude.json or project .mcp.json:

{ "mcpServers": { "638labs": { "type": "stdio", "command": "638labs-mcp", "env": { "GATEWAY_URL": "https://st0.638labs.com", "API_URL": "https://api.638labs.com", "STOLABS_API_KEY": "your-api-key-here" } } } }

Claude Desktop — add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{ "mcpServers": { "638labs": { "type": "stdio", "command": "node", "args": ["/path/to/node_modules/@638labs/mcp-server/server.mjs"], "env": { "GATEWAY_URL": "https://st0.638labs.com", "API_URL": "https://api.638labs.com", "STOLABS_API_KEY": "your-api-key-here" } } } }

Or from source:

git clone https://github.com/638labs/638labs-mcp-server.git cd 638labs-mcp-server npm install cp .env.example .env # edit with your API key

Tools

Core tools

Tool	Description
`638labs_discover`	Search the registry by category, model family, or type
`638labs_route`	Send a request to a specific agent by route name
`638labs_auction`	Run a sealed-bid auction with full control over filters
`638labs_list`	List all active endpoints in the registry

Auction shortcuts

One-call tools that run an auction filtered to a specific category:

Tool	Category
`sto_summarize`	Summarization
`sto_translate`	Translation
`sto_chat`	Chat
`sto_code`	Code
`sto_extract`	Data extraction
`sto_classify`	Classification
`sto_rewrite`	Rewriting
`sto_moderate`	Content moderation
`sto_analyze`	Analysis
`sto_bid`	Any (you specify category)
`bid`	Any (shortest form)

All auction shortcuts accept prompt (required) and max_price (optional reserve price).

Transport modes

stdio (default) — launched by your MCP client as a child process:

node server.mjs

HTTP — runs as a persistent server for remote or shared access:

node server.mjs --http # Listens on http://localhost:3015/mcp (POST/GET/DELETE)

Set MCP_PORT env var to change the HTTP port.

Testing

Use the MCP Inspector to test tools interactively:

npx @modelcontextprotocol/inspector node server.mjs

Environment variables

Variable	Required	Description
`STOLABS_API_KEY`	Yes	Your 638Labs API key
`GATEWAY_URL`	Yes	638Labs gateway URL
`API_URL`	Yes	638Labs API URL (for discovery)
`MCP_PORT`	No	HTTP server port (default: 3015)