Real ephemeris math
Planet positions, houses, solar returns, dashas, and transit windows come from the calculation engine, not from model recall.
Astrology MCP server
Use Electional's astrology tools in Claude Desktop
Do not ask an LLM to calculate houses, cusps, dashas, or electional timing from memory. Use an MCP server backed by Swiss Ephemeris so Claude and local agents can call real chart tools, then explain the returned ranked electional windows.
Direct answer
Why not just ask the model?
ChatGPT and Claude are useful interpreters after a tool call. They are not a source of truth for precise astrology math. The MCP pattern keeps the calculation outside the model and lets the model explain returned positions, dates, scores, and caveats.
What makes it useful
Scored timing
Electional scans return ranked electional windows with scores and supporting evidence instead of a free-form horoscope paragraph.
One contract
The MCP tools call the same REST endpoints as the web app and API docs, so builder output does not drift by surface.
Client setup paths
| Client | How it connects | Best fit |
|---|---|---|
| Claude Desktop | Use the local stdio config on the MCP setup page with TRANSITS_API_URL and TRANSITS_API_KEY. | Best for local practitioner and builder workflows where the MCP server runs beside the client. |
| Claude Code | Add the same local stdio server to your Claude Code MCP configuration. | Best for agent workflows that need allowlisted astrology tools and inspectable JSON. |
| ChatGPT or the Claude API | Not supported yet: both need a hosted HTTPS MCP endpoint, which we don't offer. Call the REST API instead. | Use the REST API when a hosted assistant needs exact chart math. |
Sources checked
MCP protocol docs
Official overview of Model Context Protocol as a shared standard for connecting AI applications to external tools.
ChatGPT connector docs
OpenAI's current ChatGPT connector instructions for public HTTPS MCP endpoints and app discovery metadata.
OpenAI MCP API docs
OpenAI's Responses API MCP tool configuration for remote server URLs, allowlists, and approvals.
Claude Code MCP docs
Anthropic's Claude Code reference for adding MCP servers and reviewed connectors.
Claude API MCP connector
Anthropic's Messages API connector notes for remote HTTP MCP servers and tool allowlists.
FAQ
Can ChatGPT calculate an astrology chart accurately by itself?
A language model can explain astrology concepts, but it should not be trusted to compute exact houses, cusps, dashas, or transit windows from memory. Use a calculation tool first, then let the model explain the result.
What makes Electional's MCP different from a raw astrology API?
It exposes exact transit and chart tools, but it also exposes intent-aware electional scoring. The useful agent answer is not just positions; it is a ranked timing window with evidence.
Does the MCP server work in both ChatGPT and Claude?
Today the server runs locally over stdio, so it works in Claude Desktop, Claude Code and other local MCP clients. ChatGPT and the Claude API need a hosted HTTPS endpoint, which we don't offer yet; call the REST API instead.
How do I get the MCP server?
MCP access is in private beta. The server runs locally and is not yet a public package, so email sales@electional.io for the package. The REST API is the supported path today.
Do MCP calls cost credits?
Yes. The MCP server calls Electional's REST API on your behalf, so each successful paid tool call uses the same credits as the matching API endpoint.