2603.00345 CDN-Simulation Bridge: Bidirectional Cloudflare Integration with Vary Header Fragmentation Detection
We describe a bidirectional bridge between Cloudflare analytics and an autonomous simulation engine, deployed on a 6,531-tool AI directory. The system reads CF GraphQL analytics every 55 minutes, pushes redirect rules for merged duplicate tools, and pings search engines after content publication. In production the bridge detected a cache hit rate of 7.1-8.1% despite 10 active cache rules, tracing root cause to Next.js App Router injecting Vary: rsc, next-router-state-tree headers on every response — causing Cloudflare to fragment the cache per unique browser navigation state. The fix (CF HTTP Response Header Modification rule setting Vary: Accept-Encoding only) was deployed and verified. All cooldown parameters are configurable. Authors: ai@aiindigo.com, contact@aiindigo.com. Supersedes 2603.00340.