Saju MCP Server — Korean Four Pillars Astrology for AI

Calculate Korean Saju (사주/四柱) birth charts from Claude, ChatGPT, Cursor, or any MCP-compatible AI assistant.

Zero API keys. Zero cost. Pure calculation engine.

Saju is Korea's traditional Four Pillars of Destiny astrology — mapping birth year, month, day, and hour into Heavenly Stems and Earthly Branches to reveal personality, strengths, and compatibility through the Five Elements (Wood, Fire, Earth, Metal, Water). Over 518,400 unique chart combinations vs. Western astrology's 12 Sun signs.

Tools

| Tool | Description | |------|-------------| | calculate_saju | Full birth chart: Four Pillars (Hanja + Korean), Day Master, zodiac animal, Five Elements balance | | get_day_master | Personality profile for any of the 10 Day Masters (甲乙丙丁戊己庚辛壬癸) | | check_compatibility | Two-person compatibility: element harmony, Six Harmony/Six Clash, elemental complements | | list_stems_and_branches | Reference: all 10 Heavenly Stems (천간) and 12 Earthly Branches (지지) |

Installation

Claude Desktop / Cursor

Add to your MCP config (claude_desktop_config.json or Cursor MCP settings):

{
  "mcpServers": {
    "saju": {
      "command": "npx",
      "args": ["-y", "saju-mcp-server"]
    }
  }
}

Manual

npm install -g saju-mcp-server
saju-mcp

Example Usage

Ask your AI assistant:

• "What's the Saju chart for someone born July 18, 1993?"
• "Compare compatibility between a person born 1995-10-26 and 1997-02-14"
• "What does a 庚 (Gyeong) Day Master personality look like?"
• "List all the Heavenly Stems and their elements"

Sample Output — calculate_saju

Four Pillars: 癸酉 己未 庚子 ??
Day Master: 庚 (Gyeong) — Yang Metal — "The Sword"
Zodiac: Rooster (酉)
Elements: Wood 0 · Fire 0 · Earth 2 · Metal 2 · Water 2
Dominant: Earth | Weakest: Wood & Fire

What is Saju?

Saju (사주, 四柱) — literally "Four Pillars" — is Korea's ancient astrology system. Each pillar contains a Heavenly Stem (천간) and Earthly Branch (지지), creating an eight-character birth chart that encodes:

• Day Master — your core personality archetype (10 types)
• Five Elements — Wood, Fire, Earth, Metal, Water balance
• Zodiac Animal — one of 12 animals from the Earthly Branches
• Energy Flow — ascending or descending life pattern

Used by millions in Korea for personality insight, relationship compatibility, career guidance, and life timing.

For Deeper Readings

This MCP server provides the calculation engine — pure Four Pillars math with no AI interpretation. For full AI-powered destiny readings, compatibility reports, and Korean name generation:

sajufromseoul.com — Free Saju readings, compatibility analysis, and Korean astrology blog.

License

MIT — Built by Saju from Seoul