🔧 fix: Fix rampant pings and rate limiting

- Skips idle connection checks in `getMCPManager` to avoid unnecessary pings.
- Introduces a skipOAuthTimeout flag during initial connection to prevent timeouts during server discovery.
- Uses a lightweight connection state check instead of ping to avoid rate limits.
- Prevents refetch spam and rate limit errors when checking connection status.
- Fixes an issue where the server connection was not being disconnected.

api/config/index.js

@@ -11,12 +11,13 @@ let flowManager = null;
 
 /**
  * @param {string} [userId] - Optional user ID, to avoid disconnecting the current user.
+ * @param {boolean} [skipIdleCheck] - Skip idle connection checking to avoid unnecessary pings.
  * @returns {MCPManager}
  */
-function getMCPManager(userId) {
+function getMCPManager(userId, skipIdleCheck = false) {
   if (!mcpManager) {
     mcpManager = MCPManager.getInstance();
-  } else {
+  } else if (!skipIdleCheck) {
     mcpManager.checkIdleConnections(userId);
   }
   return mcpManager;

api/server/controllers/PluginController.js

@@ -97,7 +97,6 @@ function createServerToolsCallback() {
         return;
       }
       await mcpToolsCache.set(serverName, serverTools);
-      logger.warn(`MCP tools for ${serverName} added to cache.`);
     } catch (error) {
       logger.error('Error retrieving MCP tools from cache:', error);
     }
@@ -240,7 +239,6 @@ const getAvailableTools = async (req, res) => {
         // Check if the app-level connection is active
         try {
           const mcpManager = getMCPManager();
-          const allConnections = mcpManager.getAllConnections();
 
           const appConnection = mcpManager.getConnection(serverName);
 

api/server/controllers/UserController.js

@@ -182,7 +182,7 @@ const updateUserPluginsController = async (req, res) => {
               `[updateUserPluginsController] Disconnecting MCP connection for user ${user.id} and server ${serverName} after plugin auth update for ${pluginKey}.`,
             );
             // Don't kill the server connection on revoke anymore, user can just reinitialize the server if thats what they want
-            // await mcpManager.disconnectUserConnection(user.id, serverName);
+            await mcpManager.disconnectUserConnection(user.id, serverName);
           }
         } catch (disconnectError) {
           logger.error(

api/server/routes/mcp.js

@@ -219,7 +219,7 @@ router.get('/connection/status', requireJwtAuth, async (req, res) => {
       return res.status(401).json({ error: 'User not authenticated' });
     }
 
-    const mcpManager = getMCPManager();
+    const mcpManager = getMCPManager(null, true); // Skip idle checks to avoid ping spam
     const connectionStatus = {};
 
     // Get all MCP server names from custom config
@@ -237,12 +237,14 @@ router.get('/connection/status', requireJwtAuth, async (req, res) => {
           const userConnection = mcpManager.getUserConnectionIfExists(user.id, serverName);
           const hasUserConnection = !!userConnection;
 
-          // Determine if connected based on actual connection state
+          // Use lightweight connection state check instead of ping-based isConnected()
           let connected = false;
           if (hasAppConnection) {
-            connected = await appConnection.isConnected();
+            // Check connection state without ping to avoid rate limits
+            connected = appConnection.connectionState === 'connected';
           } else if (hasUserConnection) {
-            connected = await userConnection.isConnected();
+            // Check connection state without ping to avoid rate limits
+            connected = userConnection.connectionState === 'connected';
           }
 
           // Determine if this server requires user authentication

client/src/components/SidePanel/MCP/MCPPanel.tsx

@@ -59,6 +59,8 @@ export default function MCPPanel() {
       await Promise.all([
         queryClient.invalidateQueries([QueryKeys.tools]),
         queryClient.refetchQueries([QueryKeys.tools]),
+        queryClient.invalidateQueries([QueryKeys.mcpAuthValues]),
+        queryClient.refetchQueries([QueryKeys.mcpAuthValues]),
         queryClient.invalidateQueries([QueryKeys.mcpConnectionStatus]),
         queryClient.refetchQueries([QueryKeys.mcpConnectionStatus]),
       ]);

client/src/components/ui/MCP/MCPConfigDialog.tsx

@@ -45,13 +45,8 @@ export default function MCPConfigDialog({
 }: MCPConfigDialogProps) {
   const localize = useLocalize();
 
-  // Get connection status to determine OAuth requirements with aggressive refresh
+  // Get connection status to determine OAuth requirements
-  const { data: statusQuery } = useMCPConnectionStatusQuery({
+  const { data: statusQuery } = useMCPConnectionStatusQuery();
-    refetchOnMount: true,
-    refetchOnWindowFocus: true,
-    staleTime: 0,
-    cacheTime: 0,
-  });
   const mcpServerStatuses = statusQuery?.connectionStatus || {};
 
   // Derive real-time connection status and OAuth requirements

client/src/data-provider/Tools/queries.ts

@@ -51,9 +51,10 @@ export const useMCPConnectionStatusQuery = <TData = t.TMCPConnectionStatusRespon
     [QueryKeys.mcpConnectionStatus],
     () => dataService.getMCPConnectionStatus(),
     {
-      // refetchOnWindowFocus: false,
+      refetchOnWindowFocus: false, // Stop window focus spam
-      // refetchOnReconnect: false,
+      refetchOnReconnect: false, // Stop reconnect spam
-      // refetchOnMount: true,
+      refetchOnMount: false, // Only fetch when explicitly needed
+      staleTime: 2000, // 2 second cache to prevent excessive calls
       ...config,
     },
   );

packages/api/src/mcp/connection.ts

@@ -57,7 +57,7 @@ export class MCPConnection extends EventEmitter {
   private static instance: MCPConnection | null = null;
   public client: Client;
   private transport: Transport | null = null; // Make this nullable
-  private connectionState: t.ConnectionState = 'disconnected';
+  public connectionState: t.ConnectionState = 'disconnected';
   private connectPromise: Promise<void> | null = null;
   private readonly MAX_RECONNECT_ATTEMPTS = 3;
   public readonly serverName: string;
@@ -70,6 +70,7 @@ export class MCPConnection extends EventEmitter {
   private oauthTokens?: MCPOAuthTokens | null;
   private oauthRequired = false;
   private oauthTimeoutId: NodeJS.Timeout | null = null;
+  private skipOAuthTimeout = false; // Skip OAuth timeouts during discovery
   iconPath?: string;
   timeout?: number;
   url?: string;
@@ -79,6 +80,7 @@ export class MCPConnection extends EventEmitter {
     private readonly options: t.MCPOptions,
     userId?: string,
     oauthTokens?: MCPOAuthTokens | null,
+    skipOAuthTimeout = false, // Skip OAuth timeouts during discovery
   ) {
     super();
     this.serverName = serverName;
@@ -86,6 +88,7 @@ export class MCPConnection extends EventEmitter {
     this.iconPath = options.iconPath;
     this.timeout = options.timeout;
     this.lastPingTime = Date.now();
+    this.skipOAuthTimeout = skipOAuthTimeout;
     if (oauthTokens) {
       this.oauthTokens = oauthTokens;
     }
@@ -208,10 +211,7 @@ export class MCPConnection extends EventEmitter {
             this.emit('connectionChange', 'disconnected');
           };
 
-          transport.onerror = (error) => {
+          // Error handling is done by setupTransportErrorHandlers
-            logger.error(`${this.getLogPrefix()} SSE transport error:`, error);
-            this.emitError(error, 'SSE transport error:');
-          };
 
           transport.onmessage = (message) => {
             logger.info(`${this.getLogPrefix()} Message received: ${JSON.stringify(message)}`);
@@ -250,10 +250,7 @@ export class MCPConnection extends EventEmitter {
             this.emit('connectionChange', 'disconnected');
           };
 
-          transport.onerror = (error: Error | unknown) => {
+          // Error handling is done by setupTransportErrorHandlers
-            logger.error(`${this.getLogPrefix()} Streamable-http transport error:`, error);
-            this.emitError(error, 'Streamable-http transport error:');
-          };
 
           transport.onmessage = (message: JSONRPCMessage) => {
             logger.info(`${this.getLogPrefix()} Message received: ${JSON.stringify(message)}`);
@@ -411,6 +408,24 @@ export class MCPConnection extends EventEmitter {
           const serverUrl = this.url;
           logger.debug(`${this.getLogPrefix()} Server URL for OAuth: ${serverUrl}`);
 
+          // In startup mode, immediately emit oauthRequired and fail without timeout
+          if (this.skipOAuthTimeout) {
+            logger.info(
+              `${this.getLogPrefix()} Skip OAuth timeout: OAuth required, failing immediately without timeout`,
+            );
+
+            // Emit the event for discovery purposes
+            this.emit('oauthRequired', {
+              serverName: this.serverName,
+              error,
+              serverUrl,
+              userId: this.userId,
+            });
+
+            // Immediately throw to avoid timeout
+            throw error;
+          }
+
           const oauthTimeout = this.options.initTimeout ?? 60000;
           /** Promise that will resolve when OAuth is handled */
           const oauthHandledPromise = new Promise<void>((resolve, reject) => {
@@ -545,6 +560,12 @@ export class MCPConnection extends EventEmitter {
 
   private setupTransportErrorHandlers(transport: Transport): void {
     transport.onerror = (error) => {
+      // Suppress error logging if we're already disconnected or disconnecting
+      if (this.connectionState === 'disconnected' || this.shouldStopReconnecting) {
+        logger.debug(`${this.getLogPrefix()} Transport error during disconnect (expected):`, error);
+        return;
+      }
+
       logger.error(`${this.getLogPrefix()} Transport error:`, error);
 
       // Check if it's an OAuth authentication error
@@ -556,6 +577,15 @@ export class MCPConnection extends EventEmitter {
         }
       }
 
+      // Check if it's a rate limit error (429) - don't trigger reconnection
+      const errorMessage = error?.toString() || '';
+      if (errorMessage.includes('429') || errorMessage.includes('too many requests')) {
+        logger.warn(
+          `${this.getLogPrefix()} Rate limit error detected, not triggering reconnection`,
+        );
+        return; // Don't emit error state for rate limits
+      }
+
       this.emit('connectionChange', 'error');
     };
   }
@@ -593,14 +623,14 @@ export class MCPConnection extends EventEmitter {
         this.oauthTimeoutId = null;
       }
 
+      // Set disconnected state early to suppress error logging during cleanup
+      this.connectionState = 'disconnected';
+
       if (this.transport) {
         await this.client.close();
         this.transport = null;
       }
-      if (this.connectionState === 'disconnected') {
+
-        return;
-      }
-      this.connectionState = 'disconnected';
       this.emit('connectionChange', 'disconnected');
     } finally {
       this.connectPromise = null;
@@ -643,6 +673,11 @@ export class MCPConnection extends EventEmitter {
       return false;
     }
 
+    // Don't ping if we're disconnecting or should stop reconnecting
+    if (this.shouldStopReconnecting) {
+      return false;
+    }
+
     try {
       // Try ping first as it's the lightest check
       await this.client.ping();
@@ -656,6 +691,13 @@ export class MCPConnection extends EventEmitter {
           (error as Error)?.message.includes('method not found'));
 
       if (!pingUnsupported) {
+        // Check if it's a rate limit error - don't log as error
+        const errorMessage = (error as Error)?.message || '';
+        if (errorMessage.includes('429') || errorMessage.includes('too many requests')) {
+          logger.warn(`${this.getLogPrefix()} Ping rate limited, assuming connected`);
+          return true; // Assume still connected during rate limiting
+        }
+
         logger.error(`${this.getLogPrefix()} Ping failed:`, error);
         return false;
       }

packages/api/src/mcp/manager.ts

@@ -160,6 +160,7 @@ export class MCPManager extends EventEmitter {
   }): Promise<void> {
     const processedConfig = processMCPEnv(config);
     let tokens: MCPOAuthTokens | null = null;
+
     if (tokenMethods?.findToken) {
       try {
         /** Refresh function for app-level connections */
@@ -204,10 +205,13 @@ export class MCPManager extends EventEmitter {
         logger.debug(`[MCP][${serverName}] No existing tokens found`);
       }
     }
+
     if (tokens) {
       logger.info(`[MCP][${serverName}] Loaded OAuth tokens`);
     }
-    const connection = new MCPConnection(serverName, processedConfig, undefined, tokens);
+
+    // Create connection in startup mode to prevent OAuth timeouts
+    const connection = new MCPConnection(serverName, processedConfig, undefined, tokens, true);
 
     // Track OAuth skipped state explicitly
     let oauthSkipped = false;
@@ -347,7 +351,8 @@ export class MCPManager extends EventEmitter {
     while (attempts < maxAttempts) {
       try {
         await connection.connect();
-        if (await connection.isConnected()) {
+        // Use lightweight connection state check instead of ping
+        if (connection.connectionState === 'connected') {
           return;
         }
         throw new Error('Connection attempt succeeded but status is not connected');
@@ -493,7 +498,8 @@ export class MCPManager extends EventEmitter {
       }
       connection = undefined; // Force creation of a new connection
     } else if (connection) {
-      if (await connection.isConnected()) {
+      // Use lightweight connection state check instead of ping
+      if (connection.connectionState === 'connected') {
         logger.debug(`[MCP][User: ${userId}][${serverName}] Reusing active connection`);
         this.updateUserLastActivity(userId);
         return connection;
@@ -636,7 +642,8 @@ export class MCPManager extends EventEmitter {
       });
       await Promise.race([connectionAttempt, connectionTimeout]);
 
-      if (!(await connection?.isConnected())) {
+      // Use lightweight connection state check instead of ping
+      if (connection?.connectionState !== 'connected') {
         throw new Error('Failed to establish connection after initialization attempt.');
       }
 
@@ -747,7 +754,8 @@ export class MCPManager extends EventEmitter {
     flowManager: FlowStateManager<MCPOAuthTokens | null>;
     skipReconnect?: boolean;
   }): Promise<boolean> {
-    if (await connection.isConnected()) {
+    // Use lightweight connection state check instead of ping
+    if (connection.connectionState === 'connected') {
       return true;
     }
 
@@ -775,7 +783,8 @@ export class MCPManager extends EventEmitter {
         flowManager,
       });
 
-      if (await connection.isConnected()) {
+      // Use lightweight connection state check instead of ping
+      if (connection.connectionState === 'connected') {
         logger.info(`[MCP][${serverName}] App-level connection successfully reconnected`);
         return true;
       } else {
@@ -959,7 +968,8 @@ export class MCPManager extends EventEmitter {
         }
       }
 
-      if (!(await connection.isConnected())) {
+      // Use lightweight connection state check instead of ping
+      if (connection.connectionState !== 'connected') {
         /** May happen if getUserConnection failed silently or app connection dropped */
         throw new McpError(
           ErrorCode.InternalError, // Use InternalError for connection issues