@saroday/mcp-server

MCP (Model Context Protocol) server for Saroday — Korean Saju (사주) calculation and myeongni-hak (命理學) glossary lookup.

This MCP server lets Claude Desktop, Cline, Cursor, and any other MCP-compatible AI client perform accurate Korean Saju (Four Pillars of Destiny) calculation by calling the public Saroday API under the hood.

What it does

When connected, the AI client gains access to four tools:

Why this matters: ChatGPT, Claude, and other LLMs frequently miscalculate Saju when asked directly because manse-ryeok (萬歲曆) lookup and 절기 (jeolgi) boundary handling require precise data. This MCP delegates the math to a verified server while letting the AI focus on the interpretation.

Installation

Option A — npx (no install)

npx @saroday/mcp-server

Option B — global install

npm install -g @saroday/mcp-server
saroday-mcp

Option C — clone and run

git clone https://github.com/saroday/mcp-server.git
cd mcp-server
npm install
node index.js

Requires Node.js 18 or newer.

Configure Claude Desktop

Edit your Claude Desktop config file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

Add (or merge) the following:

{
  "mcpServers": {
    "saroday": {
      "command": "npx",
      "args": ["-y", "@saroday/mcp-server"]
    }
  }
}

Restart Claude Desktop. You should see "saroday" listed in the MCP servers panel (the plug icon in the input area).

Local development (running from cloned repo)

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

Configure Cline / Cursor / other MCP clients

Any MCP client that supports stdio transport works. Point it at the saroday-mcp binary or node index.js. See your client's docs for the exact config format.

Try it out

After connecting, ask Claude things like:

• "My birthday is March 15, 1992 at 10am. Calculate my Korean Saju."
• "What does 도화살 (dohwa-sal) mean in Korean fortune-telling?"
• "내 사주 봐줘. 1990년 5월 20일 음력 14시 여성."
• "제왕(jeokwang) 12-unseong이 뭐야?"

Claude will automatically invoke calculate_saju or lookup_glossary and give you a polished interpretation based on the structured data returned.

Environment variables

Rate limits

The public Saroday API allows 100 requests per hour per IP for free use. Heavy users — apps shipping to many end-users, AI agents handling many concurrent users — should request an API key (coming soon) for higher quotas.

Contact: [email protected]

How it works

[User in Claude Desktop]
        ↓ types "내 사주 봐줘"
[Claude Desktop]
        ↓ calls calculate_saju via MCP stdio
[saroday-mcp (this package, runs locally)]
        ↓ HTTPS POST /api/v1/saju
[saroday.com server]
        ↓ runs verified manse-ryeok algorithm
[result JSON]
        ↑ flows back through the chain
[Claude] writes a beautiful Korean interpretation

This MCP package is a thin adapter — all calculation lives on Saroday's servers, so updates to the algorithm or glossary roll out without you having to upgrade the package.

Differentiators

• Manse-ryeok accuracy — handles 절기 (solar terms) boundaries that LLMs routinely get wrong (verified against @fullstackfamily/manseryeok library)
• 80+ glossary entries (~400 interpretation fields) — every sinsal, hapchung, sipseong, 12-unseong term has summary / meaning / positive / negative / practical-tip interpretation written in friendly Korean
• Korean myeongni-hak tradition — based on 적천수(滴天髓), 자평진전(子平真詮), 궁통보감(窮通寶鑑) references
• Three-channel exposure — same algorithm available as web service (saroday.com), public REST API (saroday.com/api/v1), and MCP server (this package). Pick the channel that fits your integration.

License

MIT

Support

• Web: https://saroday.com
• API docs: https://saroday.com/api/docs
• LLM-friendly index: https://saroday.com/llms.txt
• Email: [email protected]