# 20-Min Call with Mario Garza

> Twenty minutes. We'll look at what's costing you jobs right now, and what it takes to fix it. No pitch, no jargon. If we're not a fit, we'll tell you that too.

- Host: Mario Garza
- Duration: 20 min
- Location: Attendee phone number
- Host time zone: America/Los_Angeles
- Confirmation: Bookings are confirmed instantly.
- Booking page: https://cal.com/catalystdigitalsolutions/20min
- Event type id: 6359100

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=6359100&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": 6359100,
  "start": "<UTC ISO 8601 start from the slots response>",
  "attendee": {
    "name": "…",
    "email": "…",
    "timeZone": "<IANA time zone>"
  },
  "location": {
    "type": "attendeePhone",
    "phone": "…"
  },
  "guests": [
    "guest@example.com"
  ],
  "bookingFieldsResponses": {
    "notes": "…",
    "What-s-your-biggest-bottleneck-right-now": "…",
    "Company-Name": "…"
  }
}
```

- Required fields: `name` (Your name), `email` (Email address)
- Optional fields: `notes` (Additional notes), `guests` (Add guests), `What-s-your-biggest-bottleneck-right-now` (What's your biggest bottleneck right now?), `Company-Name` (Company Name?)
- `name` and `email` go in `attendee` and `guests` is a list of emails; every other field goes in `bookingFieldsResponses` under its name.
- `location` is required: `location.phone` is the attendee’s own.