At least there couldl be one-liner page saying where is the official complete documentation. Reproducible: Always Steps to Reproduce: 1. 2. 3.
Unless you are able to point to an *existing* man page in the tarball(s) or other package(s) distributed by upstream and it's an actual ebuild omission to install them, please refrain from filing such bugs. It's not a job for Gentoo developers to produce documentation for packages which they have not written themselves nor they have time to do so. Thanks for understanding.