Got any good pointers to documentation for making the transition? I'd like to pull the trigger for OpenCode and OpenRouter as well.

I just installed it and continued about my business. I don't have a carefully tuned claude code setup. It has some skills, some CLAUDE.md files, and not much else.

I did also migrate an app from Claude SDK to Pydantic AI to get off claude API pricing. https://pydantic.dev/docs/ai/overview/