There are several parameters that can be used to track a conversion using our REST API. Among these is the visitor id. Using the visitor id has an important caveat that you will need to consider before deciding which approach you will take for tracking conversions.
As explained in the API docs, you can read the tap.vid property on our Javascript API in order to track a conversion. This property contains an anonymous visitor id that we use to store important information on our end. This information includes which affiliate brought this specific visitor to your website. As we operate based on the industry standard paradigm of “last cookie counts”, we award the commission to the last affiliate that sent this visitor to your website.
Now, if you are planning on storing the content of tap.vid, to use for a conversion on a later date, for example, because you have a long sales funnel or want to award recurring commission, the last affiliate which is tied to the visitor id might have changed. This means that the commission will get awarded to the wrong affiliate. In other words: only use the tap.vid property in conjunction with the REST conversion API if you will track the conversion at the actual moment that it happens.
We have other means of dealing with long sales funnels (namely a commission approval API) and recurring/lifetime commissions.
The simple workflow for recurring/lifetime commissions is described in this article.