0n3
MCP servers · Calendly · connector · GPT action

Connect ChatGPT to Calendly

One line gives ChatGPT your Calendly account as tools: 3 endpoints, events, event types, more, called with your own connection. No key in the prompt, a receipt for every call, revoke ChatGPT's access alone any time.

Get the line for ChatGPTConnect Calendly first

Three steps

  1. Create a free 0n3 account and connect Calendly. Paste a key or sign in; it lands in your vault, encrypted.
  2. Install 0n3 into ChatGPT. A custom connector in Developer mode, or an Action on a custom GPT from the OpenAPI spec.
  3. Ask ChatGPT: whoami. Then: "List events in Calendly".
Custom connector (needs Developer mode)
  1. Settings → Connectors (or Apps) → Advanced → Developer mode on
  2. Create → name 0n3 · MCP server URL https://0n3.app/mcp · Authentication: OAuth
  3. Finish the sign-in with your 0n account
  4. Enable the connector in a chat and ask: "whoami"

ChatGPT connectors cannot send a static header, so 0n3 signs you in through its OAuth door (dynamic client registration is on).

The line above carries a placeholder; 0n3.app/install mints a real key named for ChatGPT and fills it in.

What ChatGPT can then do in Calendly

Events · List scheduled events1
List eventsGET /scheduled_events
Event types · List event types1
List event typesGET /event_types
More · Everything else this app exposes.1
Get an userGET /users/me

Calendly in other AI clients

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ChatGPT with other apps

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