The license demands that

[...] both that copyright notice and this permission notice appear in supporting documentation [...]

which pkg.go.dev clearly does not do. So the choice of not displaying the documentation is justified.

Edit: And your title is incorrect as you can clearly see from the screenshot that an MIT license variant was detected.

I see. Thanks for the clarification!

After moving the license for wayinfo.h from the LICENSE file into the source file at include/wayinfo.h, thus having just one license in the LICENSE file, the documentation for the package is generated and displayed correctly at pkg.go.dev.

I also changed the license from MIT to BSD-3 for the files that are not in include/wayinfo.h.

Moving license text around in the project made pkg.go.dev generate the API documentation. Is this is expected behavior, or an issue with the documentation generator?

Currently go.dev uses github.com/google/licensecheck to detect a projects license which just has a list of files it goes over. It is a simple tool that does not traverse all files and neither does it look for source code comments that may be a license texts.

Here is the current official policy of go.dev along with a list of all the files that are consulted: https://pkg.go.dev/license-policy

Using a simple license checker tool instead of a more advanced one is a bug in the pkg.go.dev website, then.

Here is the wallutils commit that was the latest commit on main when this issue was first created: be7e0a39ddba14d7f04f2bf2ef22e739a41f54ab

the license checker correctly identified it as both HPND-sell-variant and MIT
the issue should be that HPND-sell-variant hasn't been approved

Also, the HPND-sell-variant license only applies to the C header file wayinfo.h, that is not used when generating the documentation.

Looks like it is working now? If you put HPND-sell-variant in your LICENSE file, then pkgsite (and some people) will assume it applies to the whole repo. But it looks like you've taken it out, which will make sense to both pkgsite and people. So I believe this can be closed.

Yes. Thanks for looking into this! I appreciate the automatic generation of documentation at pkg.go.dev.