# Saju Pillars

> A Korean saju (사주팔자, "four pillars of destiny") chart maker and reader. From a Gregorian or Korean lunar (음력) birth
> date, time and place, the browser computes the year, month, day and hour pillars - the year turning at the Start of Spring and the
> month at each solar term, both found from the Sun's apparent longitude; the day and hour on local mean solar time
> (4 minutes per degree of longitude from the time-zone meridian, minus summer time; the day turns at 23:00). It shows
> the ten gods of every stem and branch, the five-element count on a wheel with the generating and controlling cycles,
> a simplified day-master strength lean, clashes, six-harmony, three-harmony and stem combinations inside the chart,
> and how this year's pillar meets the chart - free, before sign-in. Two metered tasks read the chart: READING (one
> chart, one theme: overall, love, money, work, health or the year ahead; outlook bright / mixed / careful) and MATCH
> (two charts; rapport natural / workable / stretch). Every line of a reply cites chart parts by id and the page
> checks each id, the day master, the dominant element and whether clashes were mentioned.

Saju is a cultural tradition for reflection and conversation, not a prediction, and not medical, financial, legal or
relationship advice. The model receives only the computed characters - never a birth date, time or place. Births near
a solar term, in the Rat hour (23:00-01:00) or near an hour boundary are flagged, because almanacs and schools differ
there. Solar-term instants are estimates to within minutes. The three built-in examples are made-up people.

Derived from the SkillSafe agent skill @nomadamas/saju-fortune (interview-first saju readings of love, money, work,
health, the year ahead and compatibility).

## Pages

- [App](https://saju-pillars.skillsafe.ai/): enter birth details, read the chart, the wheel and this year's pillar,
  run a reading or a compatibility read.
- [API](https://saju-pillars.skillsafe.ai/api.html): the reading and match tasks over HTTP - input fields, reply
  contracts, worked examples, eight languages.
- [sajukit.js](https://saju-pillars.skillsafe.ai/sajukit.js): the free lane (pillars, ten gods, elements,
  interactions, annual pillar, cross-chart facts, reply checks); runs in node too.

## Contract in brief

- Input: `task` (reading | match), `chart` (JSON-encoded compact chart with ids Y1/Y2, M1/M2, D1/D2, H1/H2, DM, ST,
  E-<element>, X1...), for reading `focus` and `annual` (this year's pillar, ids A1/A2/AX1...), for match `partner`
  and `cross` (ids C1...), optional `question` and, for match, `reading` (an earlier reading to stay consistent with).
- Output: one JSON object per task. Lines are `{text, cite[]}`; in a match, person ids are prefixed `A:` / `B:`.