API & MCP
Everything a person can do on Skyfold Planet Conjunctions and Best Evenings, a program or AI agent can do with the same inputs and get the identical result.
HTTP API
POST https://skyfoldconjunctions.usefulweb.site/api/v1/calculate– run Skyfold Planet Conjunctions and Best EveningsGET https://skyfoldconjunctions.usefulweb.site/api/v1/tool– inputs, output schema, examples- OpenAPI 3.1: /openapi.json · /openapi.yaml
- Errors:
application/problem+json;422includes per-fielderrors.
Skyfold Planet Conjunctions and Best Evenings
Finds every close approach of the Moon, Mercury, Venus, Mars, Jupiter and Saturn, the oppositions of Mars to Neptune and the greatest elongations of Mercury and Venus, checks whether you can see them in the evening or morning twilight at your place and exports them as an .ics calendar.
| Field | Type | Default | Description |
|---|---|---|---|
location | text | "52.0907, 5.1214" | Location (latitude, longitude). Decimal degrees such as 52.09, 5.12 (north and east positive), or DMS, UTM, MGRS, Maidenhead or a plus code. |
elevation | number | 0 | Elevation above sea level |
timeZone | text | "Europe/Amsterdam" | Time zone. IANA name such as Europe/Berlin or America/New_York, or a fixed offset such as UTC+2. |
startDate | date | "2027-01-01" | From |
months | integer | 12 | Months |
planetLimit | number | 3 | Closest planet pairs within |
moonLimit | number | 3 | Moon and planet within |
includeMoon | boolean | true | Include the Moon |
visibleOnly | boolean | true | Only events visible from this place |
Example request
Utrecht, 2026
curl -X POST https://skyfoldconjunctions.usefulweb.site/api/v1/calculate -H 'content-type: application/json' -d '{"location":"52.0907, 5.1214","timeZone":"Europe/Amsterdam","startDate":"2026-01-01","months":12,"planetLimit":3,"moonLimit":3,"includeMoon":true,"visibleOnly":true}'Every result contains
inputs (normalised, defaults applied), summary, result (validated against the published schema), units, assumptions, sources, warnings, computedAt and links.
MCP (Model Context Protocol)
- Streamable HTTP endpoint:
https://skyfoldconjunctions.usefulweb.site/mcp– protocol revisions 2026-07-28 (stateless) and 2025-11-25 / 2025-06-18 / 2025-03-26 (initialize handshake). - Tools:
skyfold_conjunctions - Local stdio connector:
node src/mcp-stdio.ts --tool=skyfold-conjunctions
{
"mcpServers": {
"skyfold-conjunctions": { "type": "http", "url": "https://skyfoldconjunctions.usefulweb.site/mcp" }
}
}