GrowingAlgo WhatsApp click-to-chat links and Cloud API templates
A click-to-chat link is https://wa.me/COUNTRYCODEPHONE?text=MESSAGE. You do not need the Cloud API for a button on a page. You do need the API for approved templates you send at scale.
The phone number must include the country code with no plus and no spaces. The prefilled message should name the offer in the first two lines. “Hi” is not a campaign.
Cloud API template names are lowercase with underscores. The body is 1,024 characters. Buttons are 25. Count those boxes before Meta rejects the submit.
GA4 will not invent a source from a wa.me tap. If they must hit a landing page, put a UTM URL in the message: utm_source=whatsapp, the same utm_campaign as the ads.