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All Verticals · Voice Workflow

Appointment Booking + Confirmation SMS

When book_appointment fires, the workflow offers live Cal.com availability, re-verifies the slot before booking it atomically, and texts a confirmation — with a graceful fallback if the slot was taken.

trigger retell_tool_callmode Real-timenodes 13connectors 3

Workflow

TriggerMemoryIntegrationBranchVoiceEnd
noyesconfirmedtakenTRIGGER01Tool call:book_appointmentMEMORY02Read callerINTEGRATION03Get availabilityVOICE04Offer timesBRANCH05Slot chosen?VOICE06Offer callbackEND08End (no booking)INTEGRATION07Verify + bookBRANCH09Booked?VOICE11Apologize + take callbackINTEGRATION10Send confirmationMEMORY12Save to ZepEND13Return tool result

How it runs, step by step

  1. 01
    TRIGGER

    Tool call: book_appointment

    The agent calls book_appointment when the caller wants to schedule.

  2. 02
    MEMORY

    Read caller

    Load the caller's context from Zep.

  3. 03
    INTEGRATION

    Get availability

    Fetch open slots from Cal.com for the requested service.

  4. 04
    VOICE

    Offer times

    Read the next available times back to the caller.

  5. 05
    BRANCH

    Slot chosen?

    Branch on whether the caller picked a time.

    • if no → Offer callback
    • if yes → Verify + book
  6. 06
    VOICE

    Offer callback

    Offer a callback or an alternate day when nothing fits.

  7. 07
    INTEGRATION

    Verify + book

    Re-verify the slot is still open, then book it atomically to prevent double-booking.

  8. 08
    END

    End (no booking)

    End without a booking; a follow-up is queued.

  9. 09
    BRANCH

    Booked?

    Branch on the booking result.

    • if confirmed → Send confirmation
    • if taken → Apologize + take callback
  10. 10
    INTEGRATION

    Send confirmation

    Text the caller the confirmed time and a calendar link via Twilio.

  11. 11
    VOICE

    Apologize + take callback

    If the slot was just taken, apologize and capture a callback.

  12. 12
    MEMORY

    Save to Zep

    Persist the booking and context to memory.

  13. 13
    END

    Return tool result

    Return the booking result to the agent.