mcp/streamable: reuse transport if sessionID is given in stateless mode

ln-12 · ln-12 · commit 431e1810d7c9 · 2025-09-01T12:58:46.000+02:00
This change fixes logging not working in stateless mode as the transport (and therefore the configured log level) is not used across requests. Fixes #387
diff --git a/mcp/streamable.go b/mcp/streamable.go
@@ -308,7 +308,7 @@ func (h *StreamableHTTPHandler) ServeHTTP(w http.ResponseWriter, req *http.Reque
 			http.Error(w, "failed connection", http.StatusInternalServerError)
 			return
 		}
-		if h.opts.Stateless {
+		if sessionID == "" && h.opts.Stateless {
 			// Stateless mode: close the session when the request exits.
 			defer ss.Close() // close the fake session after handling the request
 		} else {

Original file line number	Diff line number	Diff line change
`@@ -308,7 +308,7 @@ func (h StreamableHTTPHandler) ServeHTTP(w http.ResponseWriter, req http.Reque`
`308`	`308`	`http.Error(w, "failed connection", http.StatusInternalServerError)`
`309`	`309`	`return`
`310`	`310`	`}`
`311`		`- if h.opts.Stateless {`
	`311`	`+ if sessionID == "" && h.opts.Stateless {`
`312`	`312`	`// Stateless mode: close the session when the request exits.`
`313`	`313`	`defer ss.Close() // close the fake session after handling the request`
`314`	`314`	`} else {`