Set up agentic workflows to keep documentation healthy

[weikanglim]

Summary

As we improve the repository documentation structure, we should also establish agentic workflows that help keep docs healthy over time.

Focus

• Use coding agents to help identify stale documentation paths, missing cross-links, and areas that lack clear ownership
• Establish lightweight maintenance routines for documentation health
• Make it easier to catch drift between the codebase and the docs surface
• Support a more regular cadence of documentation cleanup and improvement

Outcomes

• Documentation stays easier to navigate over time
• Common documentation issues are identified earlier
• Contributors have clearer signals when docs need attention
• The long-term docs architecture remains healthier as the repo evolves

Parent issue: #7164