I'm building a custom function for zoho writer and am a bit stumped with the initial variable. Once I have my crm record id I'm good, but how do I define a variable for that id that triggers the custom function?

Whenever I leave the id variable in my function it says it's not defined which makes sense, but how do I go about it?

Currently flexible with how it's invoked. Ideally through a zoho form or form through zoho flow, but could go through a CRM workflow too. Whatever would be easiest.