🛠️ refactor: Consolidate MCP Tool Caching (#9172)

* 🛠️ refactor: Consolidate MCP Tool Caching

* 🐍 fix: Correctly mock and utilize updateMCPUserTools in MCP route tests

api/server/services/Config/mcpToolsCache.js

@@ -0,0 +1,142 @@
+const { logger } = require('@librechat/data-schemas');
+const { CacheKeys, Constants } = require('librechat-data-provider');
+const { getCachedTools, setCachedTools } = require('./getCachedTools');
+const { getLogStores } = require('~/cache');
+
+/**
+ * Updates MCP tools in the cache for a specific server and user
+ * @param {Object} params - Parameters for updating MCP tools
+ * @param {string} params.userId - User ID
+ * @param {string} params.serverName - MCP server name
+ * @param {Array} params.tools - Array of tool objects from MCP server
+ * @returns {Promise<void>}
+ */
+async function updateMCPUserTools({ userId, serverName, tools }) {
+  try {
+    const userTools = await getCachedTools({ userId });
+
+    const mcpDelimiter = Constants.mcp_delimiter;
+    for (const key of Object.keys(userTools)) {
+      if (key.endsWith(`${mcpDelimiter}${serverName}`)) {
+        delete userTools[key];
+      }
+    }
+
+    for (const tool of tools) {
+      const name = `${tool.name}${Constants.mcp_delimiter}${serverName}`;
+      userTools[name] = {
+        type: 'function',
+        ['function']: {
+          name,
+          description: tool.description,
+          parameters: tool.inputSchema,
+        },
+      };
+    }
+
+    await setCachedTools(userTools, { userId });
+
+    const cache = getLogStores(CacheKeys.CONFIG_STORE);
+    await cache.delete(CacheKeys.TOOLS);
+    logger.debug(`[MCP Cache] Updated ${tools.length} tools for ${serverName} user ${userId}`);
+  } catch (error) {
+    logger.error(`[MCP Cache] Failed to update tools for ${serverName}:`, error);
+    throw error;
+  }
+}
+
+/**
+ * Merges app-level tools with global tools
+ * @param {import('@librechat/api').LCAvailableTools} appTools
+ * @returns {Promise<void>}
+ */
+async function mergeAppTools(appTools) {
+  try {
+    const count = Object.keys(appTools).length;
+    if (!count) {
+      return;
+    }
+    const cachedTools = await getCachedTools({ includeGlobal: true });
+    const mergedTools = { ...cachedTools, ...appTools };
+    await setCachedTools(mergedTools, { isGlobal: true });
+    const cache = getLogStores(CacheKeys.CONFIG_STORE);
+    await cache.delete(CacheKeys.TOOLS);
+    logger.debug(`Merged ${count} app-level tools`);
+  } catch (error) {
+    logger.error('Failed to merge app-level tools:', error);
+    throw error;
+  }
+}
+
+/**
+ * Merges user-level tools with global tools
+ * @param {object} params
+ * @param {string} params.userId
+ * @param {Record<string, FunctionTool>} params.cachedUserTools
+ * @param {import('@librechat/api').LCAvailableTools} params.userTools
+ * @returns {Promise<void>}
+ */
+async function mergeUserTools({ userId, cachedUserTools, userTools }) {
+  try {
+    if (!userId) {
+      return;
+    }
+    const count = Object.keys(userTools).length;
+    if (!count) {
+      return;
+    }
+    const cachedTools = cachedUserTools ?? (await getCachedTools({ userId }));
+    const mergedTools = { ...cachedTools, ...userTools };
+    await setCachedTools(mergedTools, { userId });
+    const cache = getLogStores(CacheKeys.CONFIG_STORE);
+    await cache.delete(CacheKeys.TOOLS);
+    logger.debug(`Merged ${count} user-level tools`);
+  } catch (error) {
+    logger.error('Failed to merge user-level tools:', error);
+    throw error;
+  }
+}
+
+/**
+ * Clears all MCP tools for a specific server
+ * @param {Object} params - Parameters for clearing MCP tools
+ * @param {string} [params.userId] - User ID (if clearing user-specific tools)
+ * @param {string} params.serverName - MCP server name
+ * @returns {Promise<void>}
+ */
+async function clearMCPServerTools({ userId, serverName }) {
+  try {
+    const tools = await getCachedTools({ userId, includeGlobal: !userId });
+
+    // Remove all tools for this server
+    const mcpDelimiter = Constants.mcp_delimiter;
+    let removedCount = 0;
+    for (const key of Object.keys(tools)) {
+      if (key.endsWith(`${mcpDelimiter}${serverName}`)) {
+        delete tools[key];
+        removedCount++;
+      }
+    }
+
+    if (removedCount > 0) {
+      await setCachedTools(tools, userId ? { userId } : { isGlobal: true });
+
+      const cache = getLogStores(CacheKeys.CONFIG_STORE);
+      await cache.delete(CacheKeys.TOOLS);
+
+      logger.debug(
+        `[MCP Cache] Removed ${removedCount} tools for ${serverName}${userId ? ` user ${userId}` : ' (global)'}`,
+      );
+    }
+  } catch (error) {
+    logger.error(`[MCP Cache] Failed to clear tools for ${serverName}:`, error);
+    throw error;
+  }
+}
+
+module.exports = {
+  mergeAppTools,
+  mergeUserTools,
+  updateMCPUserTools,
+  clearMCPServerTools,
+};