# Yuko with Ramesh - Building Yuko & Retainful

> 15 minutes on what's bringing your customers back — and what's quietly losing them. See how brands use Yuko to drive more sales.

- Host: Ramesh - Building Yuko & Retainful
- Duration: 15 min
- Location: Google Meet
- Host time zone: Asia/Kolkata
- Confirmation: Bookings are confirmed instantly.
- Booking page: https://cal.com/rameshelamathi/yuko-demo
- Event type id: 2467414

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=2467414&start=YYYY-MM-DD&end=YYYY-MM-DD&timeZone=<IANA time zone>
cal-api-version: 2024-09-04
```

The response is `{"data":{"YYYY-MM-DD":[{"start":"<ISO 8601 with offset>"}]}}`; no API key is needed.

## Book

```http
POST https://api.cal.com/v2/bookings
cal-api-version: 2026-02-25
Content-Type: application/json

{
  "eventTypeId": 2467414,
  "start": "<UTC ISO 8601 start from the slots response>",
  "attendee": {
    "name": "…",
    "email": "…",
    "timeZone": "<IANA time zone>"
  },
  "guests": [
    "guest@example.com"
  ],
  "bookingFieldsResponses": {
    "attendeePhoneNumber": "…",
    "notes": "…",
    "currentapps": "…"
  }
}
```

- Required fields: `name` (Your name), `email` (Email address), `attendeePhoneNumber` (Phone Number)
- Optional fields: `notes` (Additional notes), `guests` (Add guests), `currentapps` (Which Reviews / Loyalty / Referral apps you're currently using?)
- `name` and `email` go in `attendee` and `guests` is a list of emails; every other field goes in `bookingFieldsResponses` under its name.