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 Astrology in ChatGPT and Claude
Do not ask an LLM to calculate houses, cusps, dashas, or electional timing from memory. Use an MCP server backed by Swiss Ephemeris so ChatGPT, Claude, and 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.
ChatGPT and Claude setup paths
| Client | How it connects | Best fit |
|---|---|---|
| ChatGPT | Use a public HTTPS MCP endpoint through ChatGPT Apps or connectors, or call the REST API directly while a hosted connector is being prepared. | Best when the user wants an assistant to fetch exact chart math before explaining it. |
| 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 or Claude API | Use Claude Code MCP configuration or Anthropic's remote MCP connector when you have a public HTTP server. | Best for agent workflows that need allowlisted astrology tools and inspectable JSON. |
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.
Directory-ready profile
Electional MCP
Swiss Ephemeris astrology MCP server for ChatGPT, Claude, and agents, with exact transits, solar returns, Vedic Chart, Month Ahead, and ranked electional timing.
Electional MCP gives AI assistants real astrology calculation tools instead of asking the model to guess chart math. It exposes REST-backed Swiss Ephemeris tools for transit windows, electional scoring, solar returns, Timeline, Month Ahead, and Vedic Chart reports.
Keywords: astrology, mcp, swiss ephemeris, electional astrology, chatgpt, claude, vedic chart, transits
Live directory submission still requires directory account access after deploy; this page is the public submission target.
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?
Yes, with the right host setup. ChatGPT Apps/connectors expect a public HTTPS MCP endpoint. Claude Desktop can use local stdio config, while Claude Code and the Claude API can use MCP server configuration or remote connectors.
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.