Interesting. Claude places breakpoints. Afaik - no way to do mid message.

I believe (but not positive) there are 4 breakpoints.

1. End of tool definitions

2. End of system prompt

3. End of messages thread

4. (Least sure) 50% of the way through messages thread?

This is how I've seen it done in open source things / seems optimal based on constraints of anthropic API (max 4 breakpoints)