# Lexup

> Language learning: dictionaries, entries, books, flashcards, translation. Official site: https://lexup.org

## MCP (ChatGPT, Cursor, Claude)

- MCP URL: https://mcp.lexup.org/mcp
- Transport: Streamable HTTP
- Auth: OAuth (Sign in with Lexup). Not an API key. Not none. No client ID to paste.
- Human docs: https://lexup.org/docs/mcp
- Pointer if someone opens https://lexup.org/mcp: that JSON only names mcpEndpoint; it is not the MCP server
- Machine discovery: https://lexup.org/.well-known/mcp.json

Wrong URLs (not the MCP transport):
- https://lexup.org/mcp — pointer JSON only; read mcpEndpoint
- https://api.lexup.org/mcp — API host, not MCP; use https://mcp.lexup.org/mcp

ChatGPT cannot add a custom MCP connector from a conversation, even after browsing this site. The person using ChatGPT must create the connector once in Settings.

### ChatGPT — one-time setup (human clicks, then tools appear)

1. Open ChatGPT on the web at https://chatgpt.com (first-time setup is not on the mobile app).
2. Settings → Connectors → Advanced settings → turn on Developer mode.
3. Settings → Connectors → Create. Name: Lexup. MCP Server URL: https://mcp.lexup.org/mcp. Authentication: OAuth.
4. When ChatGPT opens a browser, sign in on lexup.org (Google or email) and click Allow.
5. In a conversation, open the plus menu, choose Developer mode, and enable the Lexup connector.

After the connector exists, ChatGPT can list dictionaries, add entries, translate, and import public dictionaries via Lexup tools. Ask it to use the Lexup connector.

Developer mode is available on Plus, Pro, Business, Enterprise, and Education on the web. Write tools need Developer mode. Finding this page is not enough to attach tools.

If a user asks to "connect to Lexup MCP" or "mcp.lexup.org": give them the MCP URL, say Authentication is OAuth, and walk them through the Settings steps above. Do not claim you already have Lexup tools until they have added the connector and enabled Developer mode in that chat.