### Answer To connect Retell AI to GoHighLevel's calendar for booking appointments, you can use N8N as an integration platform [(1) ]() . The integration allows your AI phone agent to check calendar availability and book appointments directly into GoHighLevel . The process involves: 1. Setting up Retell AI to handle inbound calls 24/7 2. Qualifying leads through natural conversation 3. Booking appointments directly into your GHL calendar 4. Connecting everything through N8N and GHL's private integrations For checking calendar availability, you'll use GoHighLevel's "get free slots" API endpoint, which requires the calendar ID and authorization token . The endpoint needs start and end date times in Unix format . To format dates for GHL, you'll need to convert the date and time to Unix format (milliseconds) . You can add days to check availability across a date range . Retell AI has launched a GHL marketplace app that can book appointments in your GHL calendar [(2) ]() . There's also a detailed workshop replay available at [retellai.com/events]() with an agent template . For custom implementations, you can create a custom function in Retell and use Make.com to get calendar availability [(3) ]() .

​ To learn more, see the sources I considered: [[1] Live Workshop: Retell x GoHighLevel Integration]() [[2] Getting a 400 error from the GoHighLevel Marketplace](https://discord.com/channels/1186424376300679209/1336434583922540605) [[3] Help need for Integration with Gohighlevel and Outbound Call initiate.](https://discord.com/channels/1186424376300679209/1321436387655815221) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.