I'm glad you've had a good experience with godoc. My experience with other syntax scanners in other languages is that they always get things wrong. By the time you've added tags to correct the mistakes, you've done more work than doczar would've required you to do.
"Comments are most often read in the code in plaintext" which inspired me to make a new syntax that's more human legible in the source. If you only need to document an argument as being a Stream, it's as simple and clear as `@argument/Stream reader`, no useless sentence of text necessary. edit - or `@argument/Stream* reader` or `@argument/Stream[] readers`.