VAST Tag Guide

856 views 21/02/2019 Roni Bar 0


The VAST tag integration is a campaign recommendation API used to access YouAppi’s video demand portfolio in real time. Publishers using this API are able to display video ads that are the most suitable for their users. YouAppi’s video real-time API is compatible with both client-to-server & server-to-server integrations.

API Request

Request Format

  • Request endpoint:
  • Request method: GET

Request Parameters

The table below includes all of the fields that are available on the request.

Parameter Description Mandatory Data Type Possible Values
access_token The partner’s key used to access the API; provided by YouAppi Yes String
request_origin The origin of the request: client or server. Yes String



app_id The publisher’s package name/bundle ID/native ID. Yes String 284809790
publisher_token A custom ID of the sub-publisher in the publisher’s system Yes String 4568
publisher_name The name of the sub-publisher No String Awesome Game
ad_unit_id ID or description of the ad unit or placement Yes String
user_id_type The device’s advertising ID type – GAID (Google Advertising ID) when the OS is Android or IDFA (ID for Advertisers) when the OS is iOS. Yes String



user_id The device’s advertising ID Yes String
ip The client’s IP address Only when request_origin = server String
ua The client’s user agent string; must be URL-encoded! Only when request_origin = server String
preferred_orientation Preferred orientation of the video No String



companion_img_sizes Additional companion banners of the same app, added to the video ad using the following format: widthxheight, separated by comma. Cannot be used with html_comp_support parameter at the same time. No String 320×480
html_comp_support Additional HTML companion ad of the same app, added to the video ad. Cannot be used with companion_img_sizes parameter at the same time. No String

1 for yes

0 for no

consent GDPR user’s consent signals the permission to process and store user’s personal information Yes (only for European users) String

1 or true

0 or false

API Response

Response Format

The response of the API is in XML format using VAST 2.0.

No Ads

If there are no ads available, the VAST tag will be empty.

Error Messages

The following is a list of potential errors you may encounter in the response.

500: Internal Server Error

This error may indicate a number of unexpected server errors, and can usually be resolved by re-submitting the request.

4xx: Client Error; may include the following:

  • Invalid access token
  • User ID is missing from request
  • Invalid user ID type
  • Invalid request origin
  • Unsupported device OS/model

The cause for these errors must be corrected before resubmitting the request.

Best Practices

  • Please note that our recommendation engine is set to work under the assumption that calls are made in real-time or close to real-time. Caching – if performed – should be short-term for the duration of one active session per user.
  • Calls can originate from either the server or the client. If the request is sent from a server, the request_origin field must say “server” and the ip and user_agent fields must be populated with the details of the client.
  • To get the best results, please allow 30,000-60,000 impressions for YouAppi’s algorithm to learn your inventory’s DNA.


Request URL Generator

access_token :

request_origin :

app_id :

publisher_token :

ad_unit_id :

user_id_type :

user_id :

Generated Request URL:


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