Technology-stack questions are exactly where a model's training data goes stale, and this replaces recollection with a dated detection from BuiltWith. The detection dates and links are the part worth using: they tell you when the technology was seen, not just that it was. Everything hinges on having a BuiltWith key, since the server is a thin wrapper around their API.
A small MCP server over the BuiltWith API for looking up a website's technology stack. It runs locally over stdio and works with any MCP-compatible assistant.
- `domain_lookup` — the technology stack for one domain, taking the domain and an optional `detailed` flag
- Technologies grouped by category — analytics, CMS, frameworks and the rest — so the answer is organised rather than a flat list
- Descriptions, detection dates and links for each technology, which is what turns "they use X" into something checkable
- A Node API client you can import directly if you want the same lookups outside MCP
A BuiltWith API key, passed as `BUILTWITH_API_KEY` either in the environment or in your client's MCP settings. Node.js 18 or higher; clone, `npm install`, `npm run build`, then point your client at the built entry point. The README notes that the MCP SDK is installed from GitHub rather than npm and gives a fallback if that dependency does not resolve. MIT licensed.