When a link needs to arrive pre-filled — a campaign source, a customer ID, a referring user's email — you shouldn't have to build a custom field just to catch it. URL Parameters let a form capture values straight from the link that opened it.
In Form Settings, open the URL Parameters panel and add a parameter:
utm_source, customer_id).user_email to the logged-in user's email, so the form still personalizes itself even without a query string.The moment the form loads, MergePoint reads the declared parameters straight from the URL's query string and stores them in session context for the rest of the form session — no field, no respondent input required.
Insert a recall token anywhere in field text — a label, instructions, or a message — using:
{{param:utm_source|Friend}}
The text after the | is the fallback shown if that parameter wasn't present in the URL.
Captured parameters are automatically carried forward if the form is shared onward (for example, a link generated mid-flow), so attribution and context aren't lost as a respondent moves between steps or forms.