fix: update SSEActor error logging (#2052)

Co-authored-by: Jo Kelly-Fenton <jkellyfenton@spotify.com>

crates/mcp-client/src/transport/mod.rs

@@ -118,6 +118,14 @@ impl PendingRequests {
     pub async fn clear(&self) {
         self.requests.write().await.clear();
     }
+
+    pub async fn len(&self) -> usize {
+        self.requests.read().await.len()
+    }
+
+    pub async fn is_empty(&self) -> bool {
+        self.len().await == 0
+    }
 }
 
 pub mod stdio;

crates/mcp-client/src/transport/sse.rs

@@ -210,8 +210,13 @@ impl SseActor {
         }
 
         // mpsc channel closed => no more outgoing messages
-        tracing::error!("SseActor: outgoing message loop ended. Clearing pending requests.");
+        let pending = pending_requests.len().await;
-        pending_requests.clear().await;
+        if pending > 0 {
+            tracing::error!("SSE stream ended or encountered an error with {pending} unfulfilled pending requests.");
+            pending_requests.clear().await;
+        } else {
+            tracing::info!("SseActor shutdown cleanly. No pending requests.");
+        }
     }
 }