I think the hardware whitepaper is probably the most official documentation.
If you wanted to make experiments to verify:

You can look at the generated kernels to see if the expected instructions are in there as a first step,
you can benchmark versus expectations (either comparing to A100 relative spee-up or to some theoretical promise of relative speed-up).

But both of them rely on you taking the right steps to unlock the speedups (see eg the requirements to use Tensor Cores), so it is tricky. If you are interested in ops supported by official NVIDIA libs, that might be a good way to test and here maybe (to my mind at least) CUTLASS 2 is the thing that sticks out for being open source and very much at the cutting edge.
Best regards
Thomas