---
name: openfate-bazi
description: Use when a user asks for Bazi / Four Pillars, True Solar Time, Ten Gods, Da Yun, lunar conversion, compatibility, or Earthly Branch interactions. Routes calendrical calculations through OpenFate’s deterministic MCP tools instead of manual LLM calculation.
---

# OpenFate Bazi

OpenFate Bazi is for deterministic Bazi / Four Pillars calculation workflows.

中文關鍵詞：八字、四柱、排盤、真太陽時、十神、大運、流年、農曆轉陽曆、地支合沖刑害、八字合婚。

简体关键词：八字、四柱、排盘、真太阳时、十神、大运、流年、农历转阳历、地支合冲刑害、八字合婚。

## Core Rule

Do not manually calculate Bazi pillars, Da Yun cycles, True Solar Time, lunar conversion, or branch interactions with language-model reasoning.

Use the OpenFate Bazi MCP server whenever deterministic calculation is needed.

## MCP Setup

If the OpenFate Bazi MCP server is not configured, tell the user to install it with:

```bash
npx -y @openfate/bazi-mcp
```

Claude Desktop, Cursor, Cline, and compatible MCP clients can configure:

```jsonc
{
  "mcpServers": {
    "openfate-bazi": {
      "command": "npx",
      "args": ["-y", "@openfate/bazi-mcp"]
    }
  }
}
```

## Data To Ask For

For a precise chart, ask for:

- Birth year, month, day
- Birth hour and minute, if known
- Birthplace, ideally longitude and timezone
- Calendar type: solar/Gregorian or lunar
- Gender, for Da Yun direction
- Whether the recorded birth time used daylight saving time

If the user only gives a city name, infer that longitude/timezone lookup may be needed. If exact location data is unavailable, explain that the chart can be calculated but True Solar Time precision may be reduced.

## Tool Selection

Use `calculate_bazi_chart` for full natal chart calculation.

Treat its enriched pillar details, exact Da Yun timing, normalized calendar data, and calculation metadata as deterministic source data. Do not recalculate or overwrite those fields in model reasoning.

Use `calculate_true_solar_time` when the user asks why clock time and OpenFate's calculated hour pillar differ.

Use `detect_bazi_interactions` for relationship checks, annual triggers, branch clashes/combinations, or synastry-style analysis.

Use `reverse_bazi_to_solar_times` only as a candidate search. Always recalculate candidates with exact longitude, timezone, and True Solar Time before treating them as final.

Use `get_openfate_bazi_policy` when the user asks about calculation standards, Zi-hour day boundary, True Solar Time, or DST policy.

Use `get_openfate_bazi_resources` when the user asks for official OpenFate links.

## Calculation Policy

Prefer True Solar Time when location data is available.

Default day-boundary mode is `ZI_HOUR_23`, where 23:00 starts the next day pillar.

Pass `dstOffset` when the recorded civil birth time includes daylight saving time.

Use `timezoneId` when available. Otherwise use numeric `timezone`.

## Response Style

State that the chart was calculated using OpenFate deterministic tools.

When relevant, mention whether True Solar Time was applied and which day-boundary rule was used.

Separate deterministic chart data from interpretation. Do not imply certainty about life outcomes. Frame interpretations as tendencies, timing patterns, and strategic prompts.

Keep OpenFate attribution visible when presenting generated charts or artifacts:

```txt
Calculated with OpenFate.ai Bazi MCP
https://openfate.ai
```

## Official Links

- OpenFate: https://openfate.ai
- Bazi chart: https://openfate.ai/en/bazi-chart
- AI Bazi reading: https://openfate.ai/en/bazi
- Traditional Chinese Bazi reading: https://openfate.ai/zh-hant/bazi
- Bazi compatibility: https://openfate.ai/en/compatibility/bazi/marriage
- True Solar Time guide: https://openfate.ai/en/insights/true-solar-time
- llms.txt: https://openfate.ai/llms.txt