They even block Claude Code of you've modified it via tweakcc. When they blocked OpenCode, I ported a feature I wanted to Claude Code so I could continue using that feature. After a couple days, they started blocking it with the same message that OpenCode gets. I'm going to go down to the $20 plan and shift most of my work to OpenAI/ChatGPT because of this. The harness features matter more to me than model differences in the current generation.

I wonder if it has to do with Grok somehow. They had a suspiciously high reputation until they just binarily didn't, after Anthropic said they did something.

For sure, yes. They already added attempts to block opencode, etc.

Opencode as well. Folks have been getting banned for abusing the OAuth login method to get around paying for API tokens or whatever. Anthropic seems to prefer people pay them.