https://github.com/mitre/ig-summary/blob/main/README.md?plain=1#L11 suggests that a tgz file can be used as the input to ig-summary create, but it appears to require expanding the tgz into a package folder first. It would be more convenient to use the path to the package.tgz file without first expanding it. Also, using a URL to a package.tgz as the input parameter would also be nice; e.g.,
ig-summary create --input https://hl7.org/fhir/us/davinci-deqm/2024Sep/package.tgz ...