Why would you burn a small forest to do that? If you don't want to pay a service and know how it has to be done (you would have to develop your agent), do it by hand
In addition to my answer to your original request, I can inform about stuff related to WhatsApp.
You can use WhatsApp on a Matrix server with a bridge. You can either selfhost or find a server which has the WhatsApp bridge.
There is also Beeper - now acquired by Automattic (WordPress, ...) - which is a company matrix server with many bridges (they employed the person developing most of them). You can use a FOSS matrix client like Element X or their own client which is not FOSS but requires far fewer permissions than the WhatsApp app
I fell for it, but haven't actually used it yet. I'll stick to Deepseek, at least I know where they stand + they are not the ones that can use my data against me and probably won't hand them over to western governments (mine)
It's even worse today than last year I guess, because of the US tariffs
Edit: my bad, the article is from June 2025, the included podcast is older but they are not the same I guess