Debugging
2 articles
AI
◆Prompt Caching, End to End · Part 3
Prompt Caching (Part 3): It Is On and Not Hitting — Now What
Cache invalidation almost never errors: inference succeeds, the logs are clean, only the bill grows. Four culprits by frequency, plus a cross-vendor hit-rate self-check you can run today.
DEEP
The Mysterious 400 in Claude Multi-Turn Chats: Debugging a Thinking Signature Corruption
A customer's Claude extended-thinking conversations kept failing with 400 Invalid signature — but only on some gateway channels. A full postmortem: what the signature mechanism is, how a proxy's JSON re-serialization silently corrupts base64, five controlled experiments that pinned it down, and a fix checklist for every LLM gateway developer.