🔄 refactor: Optimize MCP Tool Initialization

🔄 refactor: Optimize MCP Tool Initialization

fix: update tool caching to use separated mcp logic

refactor: Replace `req.user` with `userId` in MCP handling functions

refactor: Replace `req` parameter with `userId` in file search tool functions

fix: Update user connection parameter to use object format in reinitMCPServer

refactor: Simplify MCP tool creation logic and improve handling of tool configurations to avoid capturing too much in closures

refactor: ensure MCP available tools are fetched from cache only when needed

api/app/clients/tools/util/fileSearch.js

@@ -68,19 +68,19 @@ const primeFiles = async (options) => {
 /**
  *
  * @param {Object} options
- * @param {ServerRequest} options.req
+ * @param {string} options.userId
  * @param {Array<{ file_id: string; filename: string }>} options.files
  * @param {string} [options.entity_id]
  * @param {boolean} [options.fileCitations=false] - Whether to include citation instructions
  * @returns
  */
-const createFileSearchTool = async ({ req, files, entity_id, fileCitations = false }) => {
+const createFileSearchTool = async ({ userId, files, entity_id, fileCitations = false }) => {
   return tool(
     async ({ query }) => {
       if (files.length === 0) {
         return 'No files to search. Instruct the user to add files for the search.';
       }
-      const jwtToken = generateShortLivedToken(req.user.id);
+      const jwtToken = generateShortLivedToken(userId);
       if (!jwtToken) {
         return 'There was an error authenticating the file search request.';
       }

api/app/clients/tools/util/handleTools.js

@@ -33,7 +33,7 @@ const { createFileSearchTool, primeFiles: primeSearchFiles } = require('./fileSe
 const { getUserPluginAuthValue } = require('~/server/services/PluginService');
 const { createMCPTool, createMCPTools } = require('~/server/services/MCP');
 const { loadAuthValues } = require('~/server/services/Tools/credentials');
-const { getCachedTools } = require('~/server/services/Config');
+const { getMCPServerTools } = require('~/server/services/Config');
 const { getRoleByName } = require('~/models/Role');
 
 /**
@@ -250,7 +250,6 @@ const loadTools = async ({
 
   /** @type {Record<string, string>} */
   const toolContextMap = {};
-  const cachedTools = (await getCachedTools({ userId: user, includeGlobal: true })) ?? {};
   const requestedMCPTools = {};
 
   for (const tool of tools) {
@@ -307,7 +306,7 @@ const loadTools = async ({
         }
 
         return createFileSearchTool({
-          req: options.req,
+          userId: user,
           files,
           entity_id: agent?.id,
           fileCitations,
@@ -340,7 +339,7 @@ Current Date & Time: ${replaceSpecialVars({ text: '{{iso_datetime}}' })}
         });
       };
       continue;
-    } else if (tool && cachedTools && mcpToolPattern.test(tool)) {
+    } else if (tool && mcpToolPattern.test(tool)) {
       const [toolName, serverName] = tool.split(Constants.mcp_delimiter);
       if (toolName === Constants.mcp_server) {
         /** Placeholder used for UI purposes */
@@ -353,33 +352,21 @@ Current Date & Time: ${replaceSpecialVars({ text: '{{iso_datetime}}' })}
         continue;
       }
       if (toolName === Constants.mcp_all) {
-        const currentMCPGenerator = async (index) =>
+        requestedMCPTools[serverName] = [
-          createMCPTools({
+          {
-            req: options.req,
+            type: 'all',
-            res: options.res,
-            index,
             serverName,
-            userMCPAuthMap,
+          },
-            model: agent?.model ?? model,
+        ];
-            provider: agent?.provider ?? endpoint,
-            signal,
-          });
-        requestedMCPTools[serverName] = [currentMCPGenerator];
         continue;
       }
-      const currentMCPGenerator = async (index) =>
+
-        createMCPTool({
-          index,
-          req: options.req,
-          res: options.res,
-          toolKey: tool,
-          userMCPAuthMap,
-          model: agent?.model ?? model,
-          provider: agent?.provider ?? endpoint,
-          signal,
-        });
       requestedMCPTools[serverName] = requestedMCPTools[serverName] || [];
-      requestedMCPTools[serverName].push(currentMCPGenerator);
+      requestedMCPTools[serverName].push({
+        type: 'single',
+        toolKey: tool,
+        serverName,
+      });
       continue;
     }
 
@@ -422,20 +409,51 @@ Current Date & Time: ${replaceSpecialVars({ text: '{{iso_datetime}}' })}
   const mcpToolPromises = [];
   /** MCP server tools are initialized sequentially by server */
   let index = -1;
-  for (const [serverName, generators] of Object.entries(requestedMCPTools)) {
+  for (const [serverName, toolConfigs] of Object.entries(requestedMCPTools)) {
     index++;
-    for (const generator of generators) {
+    /** @type {LCAvailableTools} */
+    let availableTools;
+    for (const config of toolConfigs) {
       try {
-        if (generator && generators.length === 1) {
+        const mcpParams = {
+          res: options.res,
+          userId: user,
+          index,
+          serverName: config.serverName,
+          userMCPAuthMap,
+          model: agent?.model ?? model,
+          provider: agent?.provider ?? endpoint,
+          signal,
+        };
+
+        if (config.type === 'all' && toolConfigs.length === 1) {
+          /** Handle async loading for single 'all' tool config */
           mcpToolPromises.push(
-            generator(index).catch((error) => {
+            createMCPTools(mcpParams).catch((error) => {
               logger.error(`Error loading ${serverName} tools:`, error);
               return null;
             }),
           );
           continue;
         }
-        const mcpTool = await generator(index);
+        if (!availableTools) {
+          try {
+            availableTools = await getMCPServerTools(serverName);
+          } catch (error) {
+            logger.error(`Error fetching available tools for MCP server ${serverName}:`, error);
+          }
+        }
+
+        /** Handle synchronous loading */
+        const mcpTool =
+          config.type === 'all'
+            ? await createMCPTools(mcpParams)
+            : await createMCPTool({
+                ...mcpParams,
+                availableTools,
+                toolKey: config.toolKey,
+              });
+
         if (Array.isArray(mcpTool)) {
           loadedTools.push(...mcpTool);
         } else if (mcpTool) {

api/models/Agent.js

@@ -11,7 +11,7 @@ const {
   getProjectByName,
 } = require('./Project');
 const { removeAllPermissions } = require('~/server/services/PermissionService');
-const { getCachedTools } = require('~/server/services/Config');
+const { getMCPServerTools } = require('~/server/services/Config');
 const { getActions } = require('./Action');
 const { Agent } = require('~/db/models');
 
@@ -69,8 +69,6 @@ const getAgents = async (searchParameter) => await Agent.find(searchParameter).l
  */
 const loadEphemeralAgent = async ({ req, agent_id, endpoint, model_parameters: _m }) => {
   const { model, ...model_parameters } = _m;
-  /** @type {Record<string, FunctionTool>} */
-  const availableTools = await getCachedTools({ userId: req.user.id, includeGlobal: true });
   /** @type {TEphemeralAgent | null} */
   const ephemeralAgent = req.body.ephemeralAgent;
   const mcpServers = new Set(ephemeralAgent?.mcp);
@@ -88,22 +86,18 @@ const loadEphemeralAgent = async ({ req, agent_id, endpoint, model_parameters: _
 
   const addedServers = new Set();
   if (mcpServers.size > 0) {
-    for (const toolName of Object.keys(availableTools)) {
-      if (!toolName.includes(mcp_delimiter)) {
-        continue;
-      }
-      const mcpServer = toolName.split(mcp_delimiter)?.[1];
-      if (mcpServer && mcpServers.has(mcpServer)) {
-        addedServers.add(mcpServer);
-        tools.push(toolName);
-      }
-    }
-
     for (const mcpServer of mcpServers) {
       if (addedServers.has(mcpServer)) {
         continue;
       }
-      tools.push(`${mcp_all}${mcp_delimiter}${mcpServer}`);
+      const serverTools = await getMCPServerTools(mcpServer);
+      if (!serverTools) {
+        tools.push(`${mcp_all}${mcp_delimiter}${mcpServer}`);
+        addedServers.add(mcpServer);
+        continue;
+      }
+      tools.push(...Object.keys(serverTools));
+      addedServers.add(mcpServer);
     }
   }
 

api/server/controllers/UserController.js

@@ -22,11 +22,11 @@ const {
 const { updateUserPluginAuth, deleteUserPluginAuth } = require('~/server/services/PluginService');
 const { updateUserPluginsService, deleteUserKey } = require('~/server/services/UserService');
 const { verifyEmail, resendVerificationEmail } = require('~/server/services/AuthService');
-const { getAppConfig, clearMCPServerTools } = require('~/server/services/Config');
 const { needsRefresh, getNewS3URL } = require('~/server/services/Files/S3/crud');
 const { processDeleteRequest } = require('~/server/services/Files/process');
 const { Transaction, Balance, User, Token } = require('~/db/models');
 const { getMCPManager, getFlowStateManager } = require('~/config');
+const { getAppConfig } = require('~/server/services/Config');
 const { deleteToolCalls } = require('~/models/ToolCall');
 const { getLogStores } = require('~/cache');
 
@@ -372,9 +372,6 @@ const maybeUninstallOAuthMCP = async (userId, pluginKey, appConfig) => {
   const flowId = MCPOAuthHandler.generateFlowId(userId, serverName);
   await flowManager.deleteFlow(flowId, 'mcp_get_tokens');
   await flowManager.deleteFlow(flowId, 'mcp_oauth');
-
-  // 6. clear the tools cache for the server
-  await clearMCPServerTools({ userId, serverName });
 };
 
 module.exports = {

api/server/controllers/agents/v1.js

@@ -71,7 +71,7 @@ const createAgentHandler = async (req, res) => {
     agentData.author = userId;
     agentData.tools = [];
 
-    const availableTools = await getCachedTools({ includeGlobal: true });
+    const availableTools = await getCachedTools();
     for (const tool of tools) {
       if (availableTools[tool]) {
         agentData.tools.push(tool);

api/server/controllers/assistants/v1.js

@@ -31,7 +31,7 @@ const createAssistant = async (req, res) => {
     delete assistantData.conversation_starters;
     delete assistantData.append_current_datetime;
 
-    const toolDefinitions = await getCachedTools({ includeGlobal: true });
+    const toolDefinitions = await getCachedTools();
 
     assistantData.tools = tools
       .map((tool) => {
@@ -136,7 +136,7 @@ const patchAssistant = async (req, res) => {
       ...updateData
     } = req.body;
 
-    const toolDefinitions = await getCachedTools({ includeGlobal: true });
+    const toolDefinitions = await getCachedTools();
 
     updateData.tools = (updateData.tools ?? [])
       .map((tool) => {

api/server/controllers/assistants/v2.js

@@ -28,7 +28,7 @@ const createAssistant = async (req, res) => {
     delete assistantData.conversation_starters;
     delete assistantData.append_current_datetime;
 
-    const toolDefinitions = await getCachedTools({ includeGlobal: true });
+    const toolDefinitions = await getCachedTools();
 
     assistantData.tools = tools
       .map((tool) => {
@@ -125,7 +125,7 @@ const updateAssistant = async ({ req, openai, assistant_id, updateData }) => {
 
   let hasFileSearch = false;
   for (const tool of updateData.tools ?? []) {
-    const toolDefinitions = await getCachedTools({ includeGlobal: true });
+    const toolDefinitions = await getCachedTools();
     let actualTool = typeof tool === 'string' ? toolDefinitions[tool] : tool;
 
     if (!actualTool && manifestToolMap[tool] && manifestToolMap[tool].toolkit === true) {

api/server/controllers/mcp.js

@@ -5,7 +5,11 @@
 const { logger } = require('@librechat/data-schemas');
 const { Constants } = require('librechat-data-provider');
 const { convertMCPToolToPlugin } = require('@librechat/api');
-const { getAppConfig, getMCPServerTools } = require('~/server/services/Config');
+const {
+  cacheMCPServerTools,
+  getMCPServerTools,
+  getAppConfig,
+} = require('~/server/services/Config');
 const { getMCPManager } = require('~/config');
 
 /**
@@ -49,7 +53,6 @@ const getMCPTools = async (req, res) => {
 
           // Cache server tools if found
           if (Object.keys(serverTools).length > 0) {
-            const { cacheMCPServerTools } = require('~/server/services/Config');
             await cacheMCPServerTools({ serverName, serverTools });
           }
         }

api/server/routes/mcp.js

@@ -300,9 +300,9 @@ router.post('/oauth/cancel/:serverName', requireJwtAuth, async (req, res) => {
 router.post('/:serverName/reinitialize', requireJwtAuth, async (req, res) => {
   try {
     const { serverName } = req.params;
-    const user = req.user;
+    const userId = req.user?.id;
 
-    if (!user?.id) {
+    if (!userId) {
       return res.status(401).json({ error: 'User not authenticated' });
     }
 
@@ -316,7 +316,7 @@ router.post('/:serverName/reinitialize', requireJwtAuth, async (req, res) => {
       });
     }
 
-    await mcpManager.disconnectUserConnection(user.id, serverName);
+    await mcpManager.disconnectUserConnection(userId, serverName);
     logger.info(
       `[MCP Reinitialize] Disconnected existing user connection for server: ${serverName}`,
     );
@@ -325,14 +325,14 @@ router.post('/:serverName/reinitialize', requireJwtAuth, async (req, res) => {
     let userMCPAuthMap;
     if (serverConfig.customUserVars && typeof serverConfig.customUserVars === 'object') {
       userMCPAuthMap = await getUserMCPAuthMap({
-        userId: user.id,
+        userId,
         servers: [serverName],
         findPluginAuthsByKeys,
       });
     }
 
     const result = await reinitMCPServer({
-      req,
+      userId,
       serverName,
       userMCPAuthMap,
     });

api/server/services/Config/getCachedTools.js

@@ -95,21 +95,10 @@ async function getMCPServerTools(serverName) {
   return null;
 }
 
-/**
- * Middleware-friendly function to get tools for a request
- * @function getToolsForRequest
- * @param {Object} [req] - Express request object
- * @returns {Promise<Object|null>} Available tools for the request
- */
-async function getToolsForRequest(_req) {
-  return getCachedTools();
-}
-
 module.exports = {
   ToolCacheKeys,
   getCachedTools,
   setCachedTools,
   getMCPServerTools,
-  getToolsForRequest,
   invalidateCachedTools,
 };

api/server/services/Config/mcp.js

@@ -84,45 +84,8 @@ async function cacheMCPServerTools({ serverName, serverTools }) {
   }
 }
 
-/**
- * Clears all MCP tools for a specific server
- * @param {Object} params - Parameters for clearing MCP tools
- * @param {string} params.serverName - MCP server name
- * @returns {Promise<void>}
- */
-async function clearMCPServerTools({ serverName }) {
-  try {
-    const tools = await getCachedTools();
-
-    // Remove all tools for this server
-    const mcpDelimiter = Constants.mcp_delimiter;
-    let removedCount = 0;
-    for (const key of Object.keys(tools)) {
-      if (key.endsWith(`${mcpDelimiter}${serverName}`)) {
-        delete tools[key];
-        removedCount++;
-      }
-    }
-
-    if (removedCount > 0) {
-      await setCachedTools(tools);
-
-      const cache = getLogStores(CacheKeys.CONFIG_STORE);
-      await cache.delete(CacheKeys.TOOLS);
-      // Also clear the server-specific cache
-      await cache.delete(`tools:mcp:${serverName}`);
-
-      logger.debug(`[MCP Cache] Removed ${removedCount} tools for ${serverName} (global)`);
-    }
-  } catch (error) {
-    logger.error(`[MCP Cache] Failed to clear tools for ${serverName}:`, error);
-    throw error;
-  }
-}
-
 module.exports = {
   mergeAppTools,
   cacheMCPServerTools,
-  clearMCPServerTools,
   updateMCPServerTools,
 };

api/server/services/MCP.js

@@ -22,8 +22,8 @@ const {
 } = require('librechat-data-provider');
 const { getMCPManager, getFlowStateManager, getOAuthReconnectionManager } = require('~/config');
 const { findToken, createToken, updateToken } = require('~/models');
-const { getCachedTools, getAppConfig } = require('./Config');
 const { reinitMCPServer } = require('./Tools/mcp');
+const { getAppConfig } = require('./Config');
 const { getLogStores } = require('~/cache');
 
 /**
@@ -152,8 +152,8 @@ function createOAuthCallback({ runStepEmitter, runStepDeltaEmitter }) {
 
 /**
  * @param {Object} params
- * @param {ServerRequest} params.req - The Express request object, containing user/request info.
  * @param {ServerResponse} params.res - The Express response object for sending events.
+ * @param {string} params.userId - The user ID from the request object.
  * @param {string} params.serverName
  * @param {AbortSignal} params.signal
  * @param {string} params.model
@@ -161,9 +161,9 @@ function createOAuthCallback({ runStepEmitter, runStepDeltaEmitter }) {
  * @param {Record<string, Record<string, string>>} [params.userMCPAuthMap]
  * @returns { Promise<Array<typeof tool | { _call: (toolInput: Object | string) => unknown}>> } An object with `_call` method to execute the tool input.
  */
-async function reconnectServer({ req, res, index, signal, serverName, userMCPAuthMap }) {
+async function reconnectServer({ res, userId, index, signal, serverName, userMCPAuthMap }) {
   const runId = Constants.USE_PRELIM_RESPONSE_MESSAGE_ID;
-  const flowId = `${req.user?.id}:${serverName}:${Date.now()}`;
+  const flowId = `${userId}:${serverName}:${Date.now()}`;
   const flowManager = getFlowStateManager(getLogStores(CacheKeys.FLOWS));
   const stepId = 'step_oauth_login_' + serverName;
   const toolCall = {
@@ -192,7 +192,7 @@ async function reconnectServer({ req, res, index, signal, serverName, userMCPAut
     flowManager,
   });
   return await reinitMCPServer({
-    req,
+    userId,
     signal,
     serverName,
     oauthStart,
@@ -211,8 +211,8 @@ async function reconnectServer({ req, res, index, signal, serverName, userMCPAut
  * i.e. `availableTools`, and will reinitialize the MCP server to ensure all tools are generated.
  *
  * @param {Object} params
- * @param {ServerRequest} params.req - The Express request object, containing user/request info.
  * @param {ServerResponse} params.res - The Express response object for sending events.
+ * @param {string} params.userId - The user ID from the request object.
  * @param {string} params.serverName
  * @param {string} params.model
  * @param {Providers | EModelEndpoint} params.provider - The provider for the tool.
@@ -221,8 +221,16 @@ async function reconnectServer({ req, res, index, signal, serverName, userMCPAut
  * @param {Record<string, Record<string, string>>} [params.userMCPAuthMap]
  * @returns { Promise<Array<typeof tool | { _call: (toolInput: Object | string) => unknown}>> } An object with `_call` method to execute the tool input.
  */
-async function createMCPTools({ req, res, index, signal, serverName, provider, userMCPAuthMap }) {
+async function createMCPTools({
-  const result = await reconnectServer({ req, res, index, signal, serverName, userMCPAuthMap });
+  res,
+  userId,
+  index,
+  signal,
+  serverName,
+  provider,
+  userMCPAuthMap,
+}) {
+  const result = await reconnectServer({ res, userId, index, signal, serverName, userMCPAuthMap });
   if (!result || !result.tools) {
     logger.warn(`[MCP][${serverName}] Failed to reinitialize MCP server.`);
     return;
@@ -231,8 +239,8 @@ async function createMCPTools({ req, res, index, signal, serverName, provider, u
   const serverTools = [];
   for (const tool of result.tools) {
     const toolInstance = await createMCPTool({
-      req,
       res,
+      userId,
       provider,
       userMCPAuthMap,
       availableTools: result.availableTools,
@@ -249,8 +257,8 @@ async function createMCPTools({ req, res, index, signal, serverName, provider, u
 /**
  * Creates a single tool from the specified MCP Server via `toolKey`.
  * @param {Object} params
- * @param {ServerRequest} params.req - The Express request object, containing user/request info.
  * @param {ServerResponse} params.res - The Express response object for sending events.
+ * @param {string} params.userId - The user ID from the request object.
  * @param {string} params.toolKey - The toolKey for the tool.
  * @param {string} params.model - The model for the tool.
  * @param {number} [params.index]
@@ -261,26 +269,31 @@ async function createMCPTools({ req, res, index, signal, serverName, provider, u
  * @returns { Promise<typeof tool | { _call: (toolInput: Object | string) => unknown}> } An object with `_call` method to execute the tool input.
  */
 async function createMCPTool({
-  req,
   res,
+  userId,
   index,
   signal,
   toolKey,
   provider,
   userMCPAuthMap,
-  availableTools: tools,
+  availableTools,
 }) {
   const [toolName, serverName] = toolKey.split(Constants.mcp_delimiter);
 
-  const availableTools =
-    tools ?? (await getCachedTools({ userId: req.user?.id, includeGlobal: true }));
   /** @type {LCTool | undefined} */
   let toolDefinition = availableTools?.[toolKey]?.function;
   if (!toolDefinition) {
     logger.warn(
       `[MCP][${serverName}][${toolName}] Requested tool not found in available tools, re-initializing MCP server.`,
     );
-    const result = await reconnectServer({ req, res, index, signal, serverName, userMCPAuthMap });
+    const result = await reconnectServer({
+      res,
+      userId,
+      index,
+      signal,
+      serverName,
+      userMCPAuthMap,
+    });
     toolDefinition = result?.availableTools?.[toolKey]?.function;
   }
 

api/server/services/ToolService.js

@@ -74,7 +74,7 @@ async function processRequiredActions(client, requiredActions) {
     requiredActions,
   );
   const appConfig = client.req.config;
-  const toolDefinitions = await getCachedTools({ userId: client.req.user.id, includeGlobal: true });
+  const toolDefinitions = await getCachedTools();
   const seenToolkits = new Set();
   const tools = requiredActions
     .map((action) => {

api/server/services/Tools/mcp.js

@@ -7,7 +7,7 @@ const { getLogStores } = require('~/cache');
 
 /**
  * @param {Object} params
- * @param {ServerRequest} params.req
+ * @param {string} params.userId
  * @param {string} params.serverName - The name of the MCP server
  * @param {boolean} params.returnOnOAuth - Whether to initiate OAuth and return, or wait for OAuth flow to finish
  * @param {AbortSignal} [params.signal] - The abort signal to handle cancellation.
@@ -18,7 +18,7 @@ const { getLogStores } = require('~/cache');
  * @param {Record<string, Record<string, string>>} [params.userMCPAuthMap]
  */
 async function reinitMCPServer({
-  req,
+  userId,
   signal,
   forceNew,
   serverName,
@@ -51,7 +51,7 @@ async function reinitMCPServer({
 
     try {
       userConnection = await mcpManager.getUserConnection({
-        user: req.user,
+        user: { id: userId },
         signal,
         forceNew,
         oauthStart,

api/test/app/clients/tools/util/fileSearch.test.js

@@ -46,7 +46,7 @@ describe('fileSearch.js - test only new file_id and page additions', () => {
     queryVectors.mockResolvedValue(mockResults);
 
     const fileSearchTool = await createFileSearchTool({
-      req: { user: { id: 'user1' } },
+      userId: 'user1',
       files: mockFiles,
       entity_id: 'agent-123',
     });