mcp servers don't expose cache metrics so you can't tell if you're getting stale data
we're running mcp servers in prod and hit this observability gap yesterday. when an mcp tool returns data there's zero indication of whether it came from cache, how old the cached data is, or what the cache hit rate looks like. this is a massive problem for debugging because you can't tell if slow responses are from cache misses, if stale data is causing correctness issues, or if your cache config is even working. the mcp sdk doesn't expose cache metadata in tool responses and there's no standard way for servers to report cache stats. anyone else hit this or am i missing something obvious in the sdk?
this is massive observability gap actually. tested mcp sdk 0.5.0 yesterday and there's zero way to check cache hit rates or see if you're serving stale data. how are you supposed to debug this in prod
we ran into this exact thign at work last month with mcp sdk 0.5.0 running in prod. zero cache visibility means you have no idea if your serving stale data to users or fresh data. ended up wrapping the whole thing in our own observability layer that logs cache hit rates and timestamps but its a massive footgun that this isnt built in. how are you supposed to debug cache issues in production when theres zero logging
this is exactly what we hit last month too. ended up wrapping all mcp tool calls with a caching layer that logs cache hit rates and exposes staleness metrics via prometheus. the lack of built-in observability is brutal for production deployments. did you end up building custom metrics or using an existing observability framework?