AI Receptionist

An AI receptionist answers an inbound call, understands what the caller needs and can hand structured information into an n8n workflow when an action is required.

For appointment requests, n8n checks Google Calendar for availability, creates the booking once a time is agreed, and then creates or updates the caller in HubSpot so the interaction is recorded alongside the customer.

The split is deliberate: Retell handles the conversation, while n8n coordinates the systems behind it.

Before you start

You need:

• a configured Retell AI voice agent
• an n8n instance with a public webhook endpoint
• Google Calendar credentials connected to n8n
• HubSpot credentials connected to n8n
• a clear definition of which calendar should be used for bookings
• the HubSpot fields you want to keep for the caller and interaction

Before automating the full call, test the calendar and CRM actions independently.

How to build it

1. Configure the voice agent

Create the Retell agent that answers the call and collects the information required for the workflow.

For a booking flow, that will usually include details such as the caller's name, contact information, reason for calling and preferred appointment time.

2. Connect Retell to n8n

Create a custom function in the voice flow that sends the required information to an n8n webhook.

n8n becomes the orchestration layer for actions that happen outside the conversation.

3. Check calendar availability

Use the Google Calendar integration in n8n to check whether the requested time is available.

Return the result to the calling flow so the conversation can continue if another time needs to be chosen.

4. Create the appointment

Once the caller confirms an available time, create the calendar event with the relevant caller and appointment details.

5. Update HubSpot

Search for the caller before blindly creating a new record.

Create or update the contact with the information collected during the call and record the relevant interaction details.

6. Return a clear result

Return a simple success or failure result to the voice flow.

The agent should only tell the caller that the booking succeeded after the workflow has actually completed the required action.

Things that matter

Availability before booking

Do not treat the caller's requested time as available until the calendar has actually been checked.

Duplicate records

Search before creating contacts or bookings where appropriate. Retries and repeated calls should not quietly create duplicate records.

Time zones

Keep the calendar timezone explicit. Voice conversations make phrases like "tomorrow at three" easy to misunderstand if the workflow and caller are operating in different zones.

Failure paths

Decide what happens if Calendar or HubSpot is unavailable. The voice agent needs a safe fallback instead of confidently confirming an action that failed.

Keep the voice loop fast

Only put work in the live call path that the agent needs before it can continue the conversation. Longer post-call logging or enrichment can happen after the call where appropriate.

Human handoff

Define when the receptionist should stop automating and transfer or escalate instead of trying to complete the workflow.