I see the groundhog day problem as a feature, not a bug.

It's an organizational challenge, requiring a top level overview and easy to find sub documentation - and clear directives to use them when the AI starts architecting on a fresh start.

Overall, it's a good sign when a project is understandable in small independent chunks that don't demand a programmer/llm take in more context than was referenced.

I think the sweet spot would be all agents agree on a MUST-READ reference syntax for inside comments & docs that through simple scanning forces the file into the context. eg

// See @{../docs/payment-flow.md} for the overall design.