That's exactly what you're supposed to do - if a tool generated the code in a commit, you should be using a commit trailer for that. Whether that's uniffi, an rpc preprocessor, dependabot or renovate, or some AI tool.
1. count for claude as co-author: 25M
2. count for speakeasy as co-author: 917
3. count for stainless as co-author: 6.2k
4. count for alembic as co-author: *Your search did not match any commits*
As the sibling notes, that would usually be marked as Generated-By or Generator or similar tags. Claude is only using "Co-Authored-By" for the same reason that Anthropic is calling claude "he", not "it": to anthropomorphize the machine in the public's perception.
this does not seem to match reality, see:
ex. search: https://github.com/search?q=%22Co-Authored-By%3A+Claude%22+%...