# Requirements Gathering with Vartz with Treabrolabs

> This call will focus on understanding your project requirements, goals, and expectations in detail. Led by Vardhan Gupta, we’ll discuss your vision, target audience, core features, preferred technologies, and any specific challenges or constraints. The purpose of this session is to align on the project scope, clarify objectives, and gather all the essential information needed to create a precise plan and proposal for development.

- Host: Treabrolabs
- Duration: 30 min
- Location: Google Meet
- Host time zone: Asia/Kolkata
- Confirmation: Bookings are confirmed instantly.
- Booking page: https://cal.com/treabrolabs/15min
- Event type id: 2790973

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=2790973&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": 2790973,
  "start": "<UTC ISO 8601 start from the slots response>",
  "attendee": {
    "name": "…",
    "email": "…",
    "timeZone": "<IANA time zone>"
  },
  "guests": [
    "guest@example.com"
  ],
  "bookingFieldsResponses": {
    "attendeePhoneNumber": "…",
    "Agency-Business-Name": "…",
    "title": "…"
  }
}
```

- Required fields: `name` (Your name), `email` (Email address), `attendeePhoneNumber` (Phone number)
- Optional fields: `Agency-Business-Name` (Agency/Business Name), `title` (What is this meeting about?), `guests` (Add guests)
- `name` and `email` go in `attendee` and `guests` is a list of emails; every other field goes in `bookingFieldsResponses` under its name.