datamuse-mcp

MCP server for the Datamuse API (word search, rhymes, synonyms, and more).

This project is open source, free to use, and licensed under MIT.

Purpose

This server provides simple MCP tools to:

• find synonyms, antonyms, and rhymes;
• run autocomplete;
• fetch lexical details (definitions, POS, syllables, pronunciation, frequency);
• search by spelling pattern (*, ?) or phonetic similarity.

Requirements

• Node.js >= 18
• npm

Install

npm install

Development

npm run dev

Build & run

npm run build
npm start

Manual JSON-RPC checks

# List tools
echo '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' | node dist/index.js

# Call a tool
echo '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"find_synonyms","arguments":{"word":"happy"}}}' | node dist/index.js

Claude Desktop configuration

Add this to claude_desktop_config.json:

{
  "mcpServers": {
    "datamuse": {
      "command": "node",
      "args": ["/absolute/path/to/datamuse-mcp/dist/index.js"]
    }
  }
}

Exposed tools

• find_synonyms
• find_antonyms
• find_rhymes
• find_similar_sounding
• find_by_pattern
• find_related_words
• find_adjectives_for_noun
• find_nouns_for_adjective
• get_word_info
• autocomplete

Security and limits

• The server runs over stdio (local usage recommended).
• Outbound requests go to https://api.datamuse.com.
• A local in-memory cache is used (5-minute TTL), with no disk persistence.
• Datamuse may enforce request limits/quotas.

Publishing

For npm and MCP Registry deployment, see PUBLISHING.md.

Contributing

See CONTRIBUTING.md.

License

MIT — see LICENSE.