@Mohamed Yahya For cal.com, the credential ID and external ID aren’t visible in the dashboard by default like in Calendly — they’re usually generated when you create an API key or connect an integration. Here’s what you can do: 1. Go to Settings → API Keys in your cal.com account. Create a new API key if you don’t already have one. 2. The credential ID is the unique identifier tied to that API key (shown in your keys list). 3. The external ID usually comes from the integration side (in this case Make.com). When you connect cal.com via HTTP or OAuth2, Make will assign an external ID to map the connection. 4. If you’re using the busy hours booking API, check the cal.com developer docs → “Authentication” section. It shows where both IDs appear in the JSON response. So: generate API key in cal.com → copy the ID → paste it into Make → Make assigns the external ID.