Get Mappings (Ventrata → Viator, when you open the connection in the Dashboard) – Ventrata automatically accesses your Viator account and retrieves the list of all products and options in the account, including their status and connectivity settings. Ventrata can do this because you invited it as your reservation system in Step 1.

Update Mappings (Ventrata → Viator, when you press Update Connection Mapping) – Ventrata accesses the corresponding product in your Viator account, verifies basic configurations like ticket categories, removes any previously configured availability, pricing and promotions (special offers/deals), and updates the mapping in the connectivity settings as you selected. It connects the chosen Viator option to your Ventrata option and applies the product's pricing sync setting.

Mapping catalog (POST /v2/mappings/catalog) and Mapping connect (POST /v2/mappings/connect) (Ventrata → Viator, about every hour) – Ventrata reads your Viator products and options with their mapping state (Mapped, Unmapped or Paused), and sends your mappings to Viator. These are Viator's product mapping APIs.

Tour List (POST /tourlist) (Viator → Ventrata) – Viator pulls the list of products and options available on the connection, with their Ventrata identifiers. Viator shows them on the Product Connection tab in Viator Management Center, which is the list you pick from when you map in Viator (Method 2). Ventrata answers with OCTO Get Products (GET /products).

Pricing Categories (via Calendar, Viator → Ventrata) – additionally, Viator pulls details about your product's units (ticket types) and their prices, and updates them accordingly.

Viator re-reads your product list with Tour List a few times a day per connection.

Ventrata's mapping check runs about every hour. It reads Viator's mapping catalog about every 30 minutes.

Ventrata reads and writes your Viator products from the Dashboard only when you open or update the connection.

Calendar (POST /v2/availability/calendar) (Viator → Ventrata) – Viator asks for one or more product options over a date range. Ventrata answers with each bookable date or start time, its status, the remaining capacity per ticket type, the booking cutoff and the prices. Viator uses this to fill the calendar on your product page. Ventrata answers with OCTO Availability Check (POST /availability).

Availability Check (POST /v2/availability/check) (Viator → Ventrata) – when a customer picks a product, a date and a traveler mix, Viator checks live capacity and price for that exact choice, and again as the customer moves through checkout. Ventrata answers with OCTO Availability Check.

Event Notification (POST https://api.viator.com/v2/notification/events) (Ventrata → Viator, whenever availability changes in Ventrata, for example after a booking, a cancellation, or a capacity or fare change) – Ventrata tells Viator which product options and dates changed, and how: a slot sold out or reopened (AVAILABILITY), its remaining capacity changed (CAPACITY), or its price changed (PRICING). Viator then re-reads those dates. Viator handles AVAILABILITY and PRICING updates first.

Check at booking – when a customer starts paying, Viator's Reserve call makes Ventrata check capacity again before it holds the places. So Viator can't overbook a slot that has just sold out.

Calendar: steady around the clock, which points to a scheduled background sync rather than live customer searches.

Availability Check: around the clock, busier at peak shopping hours, because it follows customers browsing.

Event Notification: Ventrata sends these around the clock, as changes happen in Ventrata.

A small number of older products still use Viator's legacy Real-time Availability call (v1.0).

We couldn't measure how far ahead Viator reads with Calendar, because the dates travel in the request body.

Calendar and Availability Check (Viator → Ventrata) – each date or start time comes back with a price per ticket type (for example Adult or Child) in your currency. Viator's API supports per-person prices, tiered per-person prices and unit prices (for example per car, boat or group).

Reseller pricing – prices come from the Viator reseller's pricing in Ventrata (retail, wholesale/commission), which the connection inherits. Viator's API can also carry a net price per ticket type. Viator uses it for operators with a net-price agreement.

Event Notification (PRICING, Ventrata → Viator) – when the retail price of a ticket type changes, including new special offers or discounts, Ventrata tells Viator, and Viator re-reads the price.

Reserve (Viator → Ventrata) – the hold keeps the price as well as the places, so the customer pays the price they were shown.

Pricing categories – Viator supports infant, child, youth, adult and senior. It uses Traveler when there's no age restriction. The categories must cover ages 0 to 99 without gaps or overlaps.

Prices come back with every Calendar and Availability Check, so Viator gets them as often as it reads availability.

Calendar and Availability Check (Viator → Ventrata) – when a promotion applies to a date, Ventrata returns the discounted retail price together with the original retail price and the special offer's ID.

Special Offers (POST /v2/product/special-offers) (Viator → Ventrata) – Viator asks for the details of those offers, such as the offer's name, type and the dates it's valid. Ventrata answers from your Ventrata promotions. Viator uses this to show a special-offer label on discounted dates. The label doesn't change the recommended retail price.

Mapping from the Dashboard – when you update a mapping, Ventrata removes special offers/deals previously set up on that Viator product, so your offers come from Ventrata.

Viator calls Special Offers around the clock, only for suppliers whose products have promotions.

Ventrata doesn't usually send Special Offers Notification calls. Viator picks up offers through Calendar and Special Offers.

Each booking starts with Reserve, then Booking. There are more holds than confirmed bookings. That's normal: holds from customers who don't finish paying simply expire.

Amendments and cancellations arrive throughout the day.

Viator emails you only when an API booking, amendment or cancellation fails (Viator's fallback). Successful API calls don't generate an email.

Redemption (POST /redemption) (Viator → Ventrata) – Viator asks for the redemption status of a confirmed booking and of each traveler on it. Ventrata finds the booking by its reference with OCTO List Bookings (GET /bookings) and answers whether the tickets were redeemed. Viator uses the answer to decide whether a cancellation or refund should be allowed.

Viator checks redemption status throughout the day, much more often than it sends cancellations.

Ventrata doesn't send redemption updates to Viator on its own.

Booking (Viator → Ventrata) – if the hotel pickup box is turned on for your Viator product, the customer picks their hotel from Viator's dropdown, and Viator sends it in the booking's pickup point field. If you collect pickup details in Viator's special requirements field instead, they arrive there.

Booking Amendment (Viator → Ventrata) – changed hotel details arrive as an amendment.

Pickup details come only with bookings and amendments. Viator's API has no call to read your Ventrata pickup points, and no separate dropoff field.

Booking (Viator → Ventrata) – information the customer enters during Viator's booking process, such as flight and cruise ship details, is sent in the question and answer fields of the booking.

Customer contact – Viator never shares the customer's real email address. It sends the phone number if the customer gives one.

Questions are set up on Viator's side. Viator's API has no call to read your Ventrata booking questions.