astral-mcp — precision-audited astrology for AI agents

Local-first MCP server that computes natal charts, transits, synastry and moon
phases from birth data. Stateless: no API key, no OAuth, no account. Every natal
chart is independently re-derived by a second ephemeris and shipped with a
precision audit (per-planet delta + verified/review status).

Package: astral-mcp (npm)
Install: npx -y astral-mcp
Binary: astral-mcp-server
Repository: https://github.com/davidmosiah/astral-mcp
MCP name: io.github.davidmosiah/astral-mcp
Author: David Mosiah — https://github.com/davidmosiah
License: MIT

Engines: circular-natal-horoscope-js (primary) cross-checked by astronomy-engine (verifier).

Recommended agent flow:
1. astral_capabilities — what this server can compute
2. astral_search_birthplace — turn a city into latitude/longitude/timezone
3. astral_compute_natal_chart — the core reading (precision-verified by default)
4. astral_current_transits / astral_synastry / astral_moon_phase — go deeper

Tools:
- astral_compute_natal_chart — planets, houses, aspects, signature, precision audit
- astral_current_transits — current + upcoming transits to a natal chart, moon phase
- astral_synastry — two-chart comparison with scored harmony/chemistry/communication/growth
- astral_moon_phase — moon phase, sign, illumination for any date (no birth data)
- astral_search_birthplace — geocode a place to lat/lon/timezone (OpenStreetMap)
- astral_demo — fully-worked example chart, no input needed
- astral_capabilities — supported house systems, zodiacs, bodies, aspects, limits
- astral_data_inventory — data domains and recommended first calls
- astral_agent_manifest — install + usage rules for agents
- astral_connection_status — health check via a sample chart + dual-engine audit

Notes:
- Pass the BIRTHPLACE timezone, not the caller's timezone.
- birth_time is optional; without it noon is assumed and the Ascendant/houses are unreliable (planet signs stay accurate).
- House systems: placidus, koch, campanus, regiomontanus, topocentric, equal-house, whole-sign. Zodiacs: tropical, sidereal.
- Returns structured astrology data only — the calling model writes any interpretation.
- Not included yet: lunar nodes, Chiron, asteroids, fixed stars, minor aspects.
