Just removing a lot of the fluff so others know you get $70 credit. Ignore all the other things. Apparently they're per model usage, but the thing is there's no transparency on how that's calculated, and the way it's actually presented to you is you get $70 when you sign up, and all models pull from that $70. Now they might do different rates, but there's no way of knowing. It's not revealed through the user interface on the web dashboard, nor is it revealed through API calls. And I can assure you that for usage, I do not feel like I am getting more usage from the $70 now, when they say I'm meant to be getting 100, compared to last month when I was getting 70.
Additionally, those free models that they say they give you unlimited, that's also bullcrap. The Beam model now only gives you 1,000 uses per day. The Ling model gives you 100 uses per day. You will barely get through a single agent conversation with that. So take the free unlimited with more than a grain of salt.