A server stamps CacheableResult hints (ttl_ms, cache_scope) onto list and
read responses; a client honours them to skip redundant round-trips. The story
will show per-result overrides on @mcp.resource() / @mcp.tool() and the
client-side cache hit/miss path.
Status: not yet implemented. Server-side stamping landed (defaults
ttl_ms=0, cache_scope="private"), but the per-result override hook and the
client honouring path are not implemented yet. An example today could only show
the defaults being emitted, not acted on.
The TypeScript SDK ships a runnable caching story:
typescript-sdk/examples/caching.