• handling resources usage also with comment in tf files, this way it's easier for user to add a estimated usage next to resource definition instead of a separate yaml file (this approach is used in tools such as tfsec https://github.com/aquasecurity/tfsec)

This is interesting. I think we could have multiple ways of specifying the usage and they all get translated into a standard format. I imagine this requires parsing the HCL code, so as long as we can match that to the resources in the plan JSON it should be good.

Yeah we can also do the same with other tools (pulumi, etc) and translate all comments into a standard format (i.e. current usage-file), which is then used to calculate pricing. Maybe we can reuse the code in tfsec project for parsing HCL code.