UTM builder
Motif reads utm_source and utm_medium on the first pageview before it looks at ad-click ids or referrers. Source and medium are lowercased. Tags after # never arrive. This builder lowercases for you.
What Motif stores
utm_source, utm_medium, utm_campaign, utm_term, and utm_content from the landing href. First non-empty source/medium pair wins. Later visits do not overwrite first touch.
Assistant presets
If you are tagging a link you control (a newsletter that mentions an assistant, or a landing you paste into a custom GPT), use source chatgpt, claude, perplexity, gemini, or copilot with medium ai_assistant so the UTM matches Motif's classified names. A natural click from chatgpt.com already sets that source from the referrer; do not double-tag in a way that disagrees.
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