Quickstart

Copy the connector URL, paste it into your MCP client, then ask a date question.

Same date, same JSON, every time — looked up, not computed live. No account needed to try the free URL below; limits and plans live on pricing.

Prefer Claude (Claude Code or Claude Desktop) for natural-language date questions. After you enable the Geometry connector once, Claude usually picks the right tool mid-thread without @ syntax. ChatGPT works on the same MCP URL but needs more explicit prompting to pick the right tool — see ChatGPT quirks below.

With or without a key

	URL
No key — try it now	`https://mcp.geometry.app/mcp`
With your key	`https://mcp.geometry.app/mcp?key=YOUR_KEY`

The keyless URL needs no account. A key comes from any Developer Portal subscription (metered Free or paid), so a key is not the same as “paid”; append it as ?key= — same shape for every client below. Details: Where your key goes.

Subscribe / Upgrade leaves geometry.app: the Developer Portal is Zuplo (keys and quotas); card checkout and invoices are Stripe. That is expected. Billing.

Pick your client

Client	Install	Notes
Claude Code	CLI `claude mcp add`	Recommended for NL + MCP
Claude Desktop	Connectors → custom URL	Recommended — stay in one thread
ChatGPT	Plugins → Server URL	Works; see quirks
Codex	`codex mcp add` / `config.toml`
Cursor	Tools & MCP → `mcp.json`
VS Code	Command Palette → `.vscode/mcp.json`

Prefer a visual? Install walkthroughs on geometry.app — animated steps for every client above.

Claude Code / CLI

claude mcp add \
  --scope user \
  --transport http \
  geometry https://mcp.geometry.app/mcp

Works immediately on the free trial URL — no signup. --scope user writes to ~/.claude.json (all projects). Confirm with /mcp inside Claude Code. Visual: tutorial · Claude Code.

Claude Desktop

Open Connectors from the compose + menu (or Settings → Connectors)
+ Add connector → Add custom connector
Name: geometry · URL: https://mcp.geometry.app/mcp
Leave Advanced settings empty (no OAuth for the free URL)
Add — then toggle geometry ON (easy to miss)
Ask a date question in a conversation

Visual: tutorial · Claude Desktop.

ChatGPT (Plugins)

Same remote MCP URL — ChatGPT calls these Plugins (Claude calls them Connectors). Free URL: Authentication = No Auth.

Install once

Settings → Security and login → Developer mode on (plan / workspace dependent)
Open chatgpt.com/plugins → + → New Plugin
Name geometry, paste https://mcp.geometry.app/mcp, set No Auth, accept the risk checkbox → Create
Connect on the consent screen — then geometry shows under Installed

Use it in a chat (more explicit syntax than Claude)

Required pattern: type @geometry, then name the tool and args. Do not rely on bare natural language or the Plugins + chip alone.

@geometry Call get_date for 1990-06-15. Confirm tool_version and temporal_context.

@geometry Call get_compatibility for 1990-06-15 and 1985-11-02. Confirm tool_version and overall score.

@geometry Call get_date for 2026-07-28. Confirm day_ruler and calendar_meta.

@geometry Call get_name for KEEL. Confirm tool and tool_version.

ChatGPT known quirks

Quirk	What you’ll see	What to do
Must `@geometry` + tool name	Without it, ChatGPT may web-search instead of calling the tool (e.g. wrong Destiny Card)	Always `@geometry Call get_…`
Tool drops mid-thread	After a success, the next ask may work in-thread, or say “tool isn’t available”	Try once with `@geometry`; if it drops → new chat
Wrong tool	Calls the wrong tool for moon / Rx / leap year / day ruler	Name `get_date` for any single-date fact (incl. `day_ruler`)
Web search mix-in	Cites mooninfo.org while claiming Geometry	“Answer ONLY from the tool JSON. Do not use web search.”
+ chip vanishes	Composer Plugins chip disappears mid-thread	Ignore the chip; use `@geometry`

Optional icon: PNG ≤10 KB from the tutorial. The free URL needs no separate GEOMETRY account. See also: OpenAI — Connect and test your plugin. Visual: tutorial · ChatGPT.

Codex

Run:

codex mcp add geometry --url https://mcp.geometry.app/mcp

Or add to ~/.codex/config.toml (project: .codex/config.toml):

[mcp_servers.geometry]
url = "https://mcp.geometry.app/mcp"

Ask a date question in Codex

Visual: tutorial · Codex.

Cursor

Cursor Settings → Tools & MCP → New MCP Server (opens mcp.json)
Add the remote server:

{
  "mcpServers": {
    "geometry": {
      "url": "https://mcp.geometry.app/mcp"
    }
  }
}

Toggle geometry ON in Tools & MCP (easy to miss)
Ask a date question in Agent

Project file: .cursor/mcp.json · global: ~/.cursor/mcp.json. Visual: tutorial · Cursor.

VS Code

Command Palette → MCP: Add Server (or MCP: Open Workspace Folder MCP Configuration)
Add to .vscode/mcp.json:

{
  "servers": {
    "geometry": {
      "type": "http",
      "url": "https://mcp.geometry.app/mcp"
    }
  }
}

MCP: List Servers — confirm geometry is Running
Ask a date question in Copilot Chat Agent mode

User profile: MCP: Open User Configuration. Key is servers (not Cursor’s mcpServers); HTTP needs "type": "http". Visual: tutorial · VS Code.

Then ask your AI

Question type	Tool	Example
Moon / season / Rx / calendars / Cosmic card / weekday / leap year / day ruler	`get_date`	”What day of the week was 2000-02-29, and was that a Gregorian leap year?”
Date identity	`get_date`	”What’s the Cosmic card for March 15, 1985?”
Weekday planetary ruler	`get_date`	”What’s the planetary day ruler for 2026-07-28?”
Two people	`get_compatibility`	”How compatible are 1985-03-15 and 1990-11-08?”
Name → cards	`get_name`	”Decode the name KEEL”

Moon phase, season, retrogrades, and day_ruler ship inside get_date. ChatGPT one-liners (copy-paste):

@geometry Call get_date for 1986-01-05.

@geometry Call get_date for 2026-07-28. Confirm day_ruler.

Full JSON in chat (same as “raw JSON”):

give raw json for date 1985-03-15 card

That tells the agent to paste the complete tool result. The tool has no verbosity flag — only date. If you read the MCP or HTTP response in code, you already get the full object every call. No account to try. Fixed lookups — same date, same answer.

Get started

Tools

Resources

Reference

With or without a key

Pick your client

Claude Code / CLI

Claude Desktop

ChatGPT (Plugins)

Install once

Use it in a chat (more explicit syntax than Claude)

ChatGPT known quirks

Codex

Cursor

VS Code

Then ask your AI

​With or without a key

​Pick your client

​Claude Code / CLI

​Claude Desktop

​ChatGPT (Plugins)

​Install once

​Use it in a chat (more explicit syntax than Claude)

​ChatGPT known quirks

​Codex

​Cursor

​VS Code

​Then ask your AI

With or without a key

Pick your client

Claude Code / CLI

Claude Desktop

ChatGPT (Plugins)

Install once

Use it in a chat (more explicit syntax than Claude)

ChatGPT known quirks

Codex

Cursor

VS Code

Then ask your AI