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@builtwith/mcp-server

v1.6.4

Published

MCP server for BuiltWith API integration

Readme

🔍 BuiltWith MCP Server 🚀

🌟 Overview

BuiltWith MCP is a Model Context Protocol (MCP) server that allows AI assistants (Claude, Cursor, IDE agents, etc.) to query BuiltWith’s technology detection data directly and natively.

It enables natural-language questions like:

“What technologies does example.com use?” “Does this site run Shopify or Magento?” “What analytics stack is used by nytimes.com?”

BuiltWith MCP supports bring-your-own BuiltWith API key and can be used either as a hosted service or self-hosted.


Claude DEMO

Shows how to get this working in Claude as a Connector

https://github.com/user-attachments/assets/1199362a-c813-497e-8569-15b9a3ce9713

🌐 Hosted MCP (Recommended)

BuiltWith provides a hosted MCP endpoint — no local Node process required.

Endpoint

https://api.builtwith.com/mcp

Authentication

Bring your own BuiltWith API key:

Authorization: Bearer YOUR_BUILTWITH_API_KEY

Example MCP request

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/list"
}

🧩 Supported Tools

The hosted MCP exposes the following tools:

  • domain-lookup – Live technology detection for a domain
  • domain-api – Full domain metadata
  • change-api – Technology additions and removals with business context
  • lists-api – Sites using a technology, including OTHERTECHS and numeric attribute filters such as SPEND, REVENUE, and EMPLOYEES
  • relationships-api – Related websites
  • free-api – Category and group counts
  • company-to-url – Company → domain discovery
  • tags-api – IP / attribute based discovery
  • recommendations-api – Technology recommendations
  • redirects-api – Live and historical redirects
  • keywords-api – Keyword intelligence
  • trends-api – Technology trend data
  • product-api – Ecommerce product search
  • trust-api – Trust scoring
  • financial-api – Financial data
  • social-api – Social profile associations
  • vector-search – Semantic similarity search across technologies and categories
  • payment-balance – Check your API credit balance
  • payment-config – Retrieve your payment configuration
  • payment-purchase – Purchase API credits using your saved Stripe payment method
  • agent-auth-start – Start Agent Device-Code Authorization (no API key required)
  • agent-auth-token – Poll for authorization result and retrieve access token (no API key required)

⚙️ Client Configuration (Claude, Cursor, IDEs)

Add BuiltWith MCP to your MCP-compatible client configuration.

Example

{
  "mcpServers": {
    "builtwith": {
      "url": "https://api.builtwith.com/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_BUILTWITH_API_KEY"
      }
    }
  }
}

Configuration locations

  • Claude Desktop

    • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
    • Windows: %APPDATA%\Claude\claude_desktop_config.json
  • Cursor / Claude Dev (VS Code)

    • macOS: ~/Library/Application Support/Code/User/globalStorage/saoudrizwan.claude-dev/settings/cline_mcp_settings.json
    • Windows: %APPDATA%\Code\User\globalStorage\saoudrizwan.claude-dev\settings\cline_mcp_settings.json

🛠️ Self-Hosting (Optional)

You can also run the BuiltWith MCP server locally or inside your own infrastructure.

What changed (February 14, 2026)

The local server now supports both standard MCP transports:

  • stdio (default) for local MCP clients like Claude Desktop/Cursor
  • http for remote/connector style MCP usage on /mcp

Installation

git clone https://github.com/builtwith/builtwith-mcp.git
cd builtwith-mcp
npm install

Local (stdio) MCP configuration

{
  "mcpServers": {
    "builtwith": {
      "command": "node",
      "args": ["[PATH-TO]/bw-mcp-v1.js"],
      "env": {
        "BUILTWITH_API_KEY": "YOUR_BUILTWITH_API_KEY"
      }
    }
  }
}

Note: The hosted endpoint is recommended for most users. Self-hosting is useful if you need custom routing, rate-limiting, or private network access.

Local HTTP MCP endpoint

Run in HTTP mode:

MCP_TRANSPORT=http PORT=8787 node bw-mcp-v1.js

MCP endpoint:

http://127.0.0.1:8787/mcp

Optional headers/environment:

  • Authorization: Bearer YOUR_BUILTWITH_API_KEY (per-request API key for HTTP mode)
  • BUILTWITH_API_KEY (used by stdio mode, and as fallback when no HTTP bearer token is provided)
  • MCP_ALLOWED_ORIGINS (comma-separated CORS/origin allowlist for HTTP mode)

Health check:

http://127.0.0.1:8787/health

🔐 Agent Device-Code Authorization

Agents can obtain a temporary bw- prefixed API token without the user pasting their key — the user approves access in their browser.

Flow:

  1. Call agent-auth-start → receive device_code and verification_uri
  2. Direct the user to open verification_uri in their browser
  3. Poll agent-auth-token every 5 seconds with the device_code
  4. On approval, receive an access_token (bw-...) valid for the chosen duration (1 hour / 1 day / 30 days)
  5. Use the token as KEY=bw-... on any BuiltWith API endpoint

No API key is required to call agent-auth-start or agent-auth-token.


🚀 Usage Examples

Once configured, try asking your AI assistant:

  • “What technologies is example.com using?”
  • “What CMS does nytimes.com run on?”
  • “Does amazon.com use Google Analytics?”
  • “What JavaScript frameworks are used by spotify.com?”
  • “What hosting provider does netflix.com use?”
  • “Compare the technology stacks of facebook.com and twitter.com”

🧠 How It Works

  1. 🗣️ User asks a technology question in an AI assistant
  2. 🔌 The assistant calls the BuiltWith MCP server
  3. 🔍 MCP translates intent into BuiltWith API calls
  4. 📊 BuiltWith returns structured technology data
  5. 💬 The AI assistant presents human-friendly insights

📖 BuiltWith API Documentation


📄 License

MIT License — see the LICENSE file for details.


Built for AI-native workflows by BuiltWith

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