keepalive calls session.Close for all errors including 404

[BadBastion]

go-sdk/mcp/shared.go

Line 610 in 4c00594

logger.Error("keepalive ping failed; closing session", "error", err)

This includes method-not-found 404s. This means a server that's perfectly healthy but doesn't implement ping gets its session killed. Since ping is optional some servers don't implement it and make keepalives hard/unsafe to enable globally.

[BadBastion]

In its current form, the only safe way to do this is to send a ping before initialize (without a Session-id to disrupt) to establish if keepalive is supported. This strikes me as ambiguity with the MCP spec itself that results in implicit problems downstream.