# Free GTM check-up with Stefan Battistetti

> A free 45-minute GTM check-up. We map how you win customers today and find where sales leak. Afterwards you get a one-page summary with the 3 fixes I'd make first, whether or not we work together. If you haven't yet, take the 5-minute test before we talk, so we spend the call on fixes, not questions: https://battistetti.com/test/ English or German.

- Host: Stefan Battistetti
- Duration: 45 min
- Location: Google Meet
- Host time zone: Europe/Berlin
- Confirmation: Bookings are confirmed instantly.
- Booking page: https://cal.com/stefan-battistetti/gtm-check-up
- Event type id: 7850737

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=7850737&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": 7850737,
  "start": "<UTC ISO 8601 start from the slots response>",
  "attendee": {
    "name": "…",
    "email": "…",
    "timeZone": "<IANA time zone>"
  },
  "guests": [
    "guest@example.com"
  ],
  "bookingFieldsResponses": {
    "notes": "…"
  }
}
```

- Required fields: `name` (Your name), `email` (Email address)
- Optional fields: `notes` (Additional notes), `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.