Hi Tom and thanks for the interest!
I will clarify in the original blog post: I’m using the API for free thanks to the Experiment plan, this seems so underrated and I get so many benefits from this that i’m surprised this is possible. This has worked too well for too long.

More info at
https://help.mistral.ai/en/articles/450104-how-can-i-try-the-api-for-free-with-the-experiment-plan

Note that I’ve also a Le Chat Pro subscription.
Cheers