Under the hoodTier: how much it should matter to you
2Useful: my rating, 1 to 5
0Signal: worth watching, 1 to 5
MCPArea: what it touches
In DevelopmentKind: in v2.1.221,
In DevelopmentSection of the release
What
Tool discovery has a second code path for servers that negotiated the modern protocol era.
Details
When the connected client reports getProtocolEra?.() === "modern", discovery calls listTools with cacheMode: "refresh" and retries retryable failures with a 250/500/1000ms backoff, logging each retry.
Pagination overruns on that path are recorded as capped.
Legacy servers keep the previous paginated tools/list walk, which is what everyone gets by default.
The large tool-conversion body was factored out of the cached discovery function into a shared helper that both live and cached results go through.
Evidence
tools/list failed (${de(n)}); retrying in ${o}ms
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
