So one of my peeves with signed fetch is it requires anybody writing a new implementation to get an awful lot of code right and up and running before you're allowed to even see if any of it is right.
When I was writing honk, running curl and looking at mastodon's responses was instrumental in seeing how objects are formatted and what fields are included. But now mastodon won't even let you see an actor object until you yourself publish a fully formed correctly formatted actor object. How are you supposed to learn in such an environment?
Step 1: achieve some success. Step 2: pull up the ladder.