cafe-mcp: Saju & BaZi (Four Pillars of Destiny) MCP server
Korean astrology (Saju, 사주) and Chinese BaZi (八字) for AI agents. Computed, not guessed. Give Claude, ChatGPT, Cursor or any MCP client a birth date and time. cafe-mcp returns the Four Pillars chart, luck cycles, a manseryeok (만세력) calendar and the classical texts as structured, reproducible data from the CAFE engine. Your AI writes the reading in the user's language.
Why not just ask the LLM? A general model improvises the chart: the same birth data gives a different Day Master on different days, and solar-term boundaries, hidden stems and luck cycles are routinely wrong. cafe-mcp calculates them with an engine built since 2019: solar terms to the second, birthplace longitude, historical time zones and daylight saving. Same input, same chart, every time.
Quick start
Server URL:
https://mcp.24plus.ai.kr/mcp
claude.ai, Claude apps, ChatGPT: add a custom connector with the URL above, sign in to 24PLUS, then allow. No key needed.
Claude Code, Cursor and other clients: either add the URL and sign in (OAuth), or create a key at https://24plus.ai.kr/my and send it as a bearer token:
claude mcp add --transport http cafe-mcp https://mcp.24plus.ai.kr/mcp --header "Authorization: Bearer mcp_live_..."
{ "mcpServers": { "cafe-mcp": { "url": "https://mcp.24plus.ai.kr/mcp", "headers": { "Authorization": "Bearer mcp_live_..." } } } }
Disconnect any time from My account > Connected AI.
Plans
| Free | Plus (launching soon) | |
|---|---|---|
| Different charts per month | 10 | 100 |
| Tool calls per month | 300 | 3,000 |
| Calls per minute | 20 | 60 |
| Engine judgments (structure, useful element, luck index) | – | ✓ |
| Classics | 3 results, translation excerpt, table of contents | 10 results, full translation, full chapters |
A chart you have already looked up does not count again. Details: https://24plus.ai.kr/pricing
Tools
| Tool | Plan | What it does |
|---|---|---|
saju_chart | Free | Four pillars with Hanja, Five Elements, Ten Gods, hidden stems, twelve life stages, stars, combinations, clashes and void |
luck_cycles | Free | Ten-year cycles with start ages, yearly and monthly pillars |
saju_reading_context | Free | Chart facts, current luck, term meanings and reading principles in one prompt-ready bundle. The best first call for a reading |
manse_calendar | Free | A month of solar and lunar dates, day pillars, exact solar-term times, auspicious days |
find_dates_by_pillars | Free | Reverse lookup: the dates and times that produce given pillars |
find_birthplace | Free | City search for longitude correction (births outside Korea) |
lookup_term | Free | 980 Saju terms in Korean, Hanja and English |
search_classics | Free | Ziping Zhenquan, Ditian Sui, Qiongtong Baojian and more, original with Korean translation |
read_classic | Free | The library and each book's table of contents (full chapters on Plus) |
chart_structure | Plus | Day Master strength (1 to 5) with its basis, element ratios, structure pattern, climate |
useful_element | Plus | Useful element candidates by five classical methods and the engine's pick |
luck_index | Plus | A 1 to 5 level for each cycle, year or month, with the reasons |
Full reference with inputs and example prompts: https://24plus.ai.kr/docs/tools
Values come back in Korean with Hanja; pass lang="en" for English term names.
Principles
- Calculation is deterministic; interpretation is left to your AI, grounded in the returned data.
- No scores or fixed predictions in the free tools. Levels describe the strength of a tendency.
- Birth data is used only for the calculation. The server keeps a one-way fingerprint for the monthly chart count, never the birth date itself. See PRIVACY.md.
Before v1.1.0
Until 2026-10-18 this URL served an open server with six tools and no sign-in, and the npm package
@dangamsoft/cafe-mcp ran it locally over stdio. Both are retired; the npm package is deprecated.
See CHANGELOG.md.
About
cafe-mcp is run by 24PLUS (Dangamsoft, Korea), built on the CAFE engine. Website: https://24plus.ai.kr · Business API (Core API): https://24plus.ai.kr/mcp#business
License: Apache-2.0 for the code in this repository.