Why do you think there's was an implicit agreement that documentation was only intended for humans? I've written a lot of documentation, much of it open source, and I'm generally very excited that it has proved additionally useful via LLMs. If you had asked me in 2010 whether that was something I intended in writing docs I'm pretty sure I would have said something like "that's science fiction, but sure".
You still intended it for humans. Intent is defined by what one is aiming for, and without knowledge of an alternative, that was your intent.
100% I get that you are OK with it being used by non-human ingestion. And I think many might be OK with that.
One thing, I'm not sure how helpful the documentation is. I think we're getting training out of example, not docs. This makes me think... we could test this by creating a new pseudo-language, and then provide no examples, only docs.
If the LLM can then code effectively after reading the docs, we'd have a successful test. Otherwise? It's all parroting.