🗝️ feat: User Provided Credentials for MCP Servers (#7980)

* 🗝️ feat: Per-User Credentials for MCP Servers

chore: add aider to gitignore

feat: fill custom variables to MCP server

feat: replace placeholders with custom user MCP variables

feat: handle MCP install/uninstall (uses pluginauths)

feat: add MCP custom variables dialog to MCPSelect

feat: add MCP custom variables dialog to the side panel

feat: do not require to fill MCP credentials for in tools dialog

feat: add translations keys (en+cs) for custom MCP variables

fix: handle LIBRECHAT_USER_ID correctly during MCP var replacement

style: remove unused MCP translation keys

style: fix eslint for MCP custom vars

chore: move aider gitignore to AI section

* feat: Add Plugin Authentication Methods to data-schemas

* refactor: Replace PluginAuth model methods with new utility functions for improved code organization and maintainability

* refactor: Move IPluginAuth interface to types directory for better organization and update pluginAuth schema to use the new import

* refactor: Remove unused getUsersPluginsAuthValuesMap function and streamline PluginService.js; add new getPluginAuthMap function for improved plugin authentication handling

* chore: fix typing for optional tools property with GenericTool[] type

* chore: update librechat-data-provider version to 0.7.88

* refactor: optimize getUserMCPAuthMap function by reducing variable usage and improving server key collection logic

* refactor: streamline MCP tool creation by removing customUserVars parameter and enhancing user-specific authentication handling to avoid closure encapsulation

* refactor: extract processSingleValue function to streamline MCP environment variable processing and enhance readability

* refactor: enhance MCP tool processing logic by simplifying conditions and improving authentication handling for custom user variables

* ci: fix action tests

* chore: fix imports, remove comments

* chore: remove non-english translations

* fix: remove newline at end of translation.json file

---------

Co-authored-by: Aleš Kůtek <kutekales@gmail.com>

packages/api/src/mcp/manager.ts

@@ -14,10 +14,6 @@ import { MCPTokenStorage } from './oauth/tokens';
 import { formatToolContent } from './parsers';
 import { MCPConnection } from './connection';
 
-export interface CallToolOptions extends RequestOptions {
-  user?: TUser;
-}
-
 export class MCPManager {
   private static instance: MCPManager | null = null;
   /** App-level connections initialized at startup */
@@ -28,7 +24,11 @@ export class MCPManager {
   private userLastActivity: Map<string, number> = new Map();
   private readonly USER_CONNECTION_IDLE_TIMEOUT = 15 * 60 * 1000; // 15 minutes (TODO: make configurable)
   private mcpConfigs: t.MCPServers = {};
-  private processMCPEnv?: (obj: MCPOptions, user?: TUser) => MCPOptions; // Store the processing function
+  private processMCPEnv?: (
+    obj: MCPOptions,
+    user?: TUser,
+    customUserVars?: Record<string, string>,
+  ) => MCPOptions; // Store the processing function
   /** Store MCP server instructions */
   private serverInstructions: Map<string, string> = new Map();
 
@@ -63,7 +63,6 @@ export class MCPManager {
     if (!tokenMethods) {
       logger.info('[MCP] No token methods provided, token persistence will not be available');
     }
-
     const entries = Object.entries(mcpServers);
     const initializedServers = new Set();
     const connectionResults = await Promise.allSettled(
@@ -382,6 +381,7 @@ export class MCPManager {
     user,
     serverName,
     flowManager,
+    customUserVars,
     tokenMethods,
     oauthStart,
     oauthEnd,
@@ -390,6 +390,7 @@ export class MCPManager {
     user: TUser;
     serverName: string;
     flowManager: FlowStateManager<MCPOAuthTokens | null>;
+    customUserVars?: Record<string, string>;
     tokenMethods?: TokenMethods;
     oauthStart?: (authURL: string) => Promise<void>;
     oauthEnd?: () => Promise<void>;
@@ -444,9 +445,8 @@ export class MCPManager {
     }
 
     if (this.processMCPEnv) {
-      config = { ...(this.processMCPEnv(config, user) ?? {}) };
+      config = { ...(this.processMCPEnv(config, user, customUserVars) ?? {}) };
     }
-
     /** If no in-memory tokens, tokens from persistent storage */
     let tokens: MCPOAuthTokens | null = null;
     if (tokenMethods?.findToken) {
@@ -752,7 +752,6 @@ export class MCPManager {
     getServerTools?: (serverName: string) => Promise<t.LCManifestTool[] | undefined>;
   }): Promise<t.LCToolManifest> {
     const mcpTools: t.LCManifestTool[] = [];
-
     for (const [serverName, connection] of this.connections.entries()) {
       try {
         /** Attempt to ensure connection is active, with reconnection if needed */
@@ -784,13 +783,21 @@ export class MCPManager {
         const serverTools: t.LCManifestTool[] = [];
         for (const tool of tools) {
           const pluginKey = `${tool.name}${CONSTANTS.mcp_delimiter}${serverName}`;
+
+          const config = this.mcpConfigs[serverName];
           const manifestTool: t.LCManifestTool = {
             name: tool.name,
             pluginKey,
             description: tool.description ?? '',
             icon: connection.iconPath,
+            authConfig: config?.customUserVars
+              ? Object.entries(config.customUserVars).map(([key, value]) => ({
+                  authField: key,
+                  label: value.title || key,
+                  description: value.description || '',
+                }))
+              : undefined,
           };
-          const config = this.mcpConfigs[serverName];
           if (config?.chatMenu === false) {
             manifestTool.chatMenu = false;
           }
@@ -814,6 +821,7 @@ export class MCPManager {
    * for user-specific connections upon successful call initiation.
    */
   async callTool({
+    user,
     serverName,
     toolName,
     provider,
@@ -823,20 +831,22 @@ export class MCPManager {
     flowManager,
     oauthStart,
     oauthEnd,
+    customUserVars,
   }: {
+    user?: TUser;
     serverName: string;
     toolName: string;
     provider: t.Provider;
     toolArguments?: Record<string, unknown>;
-    options?: CallToolOptions;
+    options?: RequestOptions;
     tokenMethods?: TokenMethods;
+    customUserVars?: Record<string, string>;
     flowManager: FlowStateManager<MCPOAuthTokens | null>;
     oauthStart?: (authURL: string) => Promise<void>;
     oauthEnd?: () => Promise<void>;
   }): Promise<t.FormattedToolResponse> {
     /** User-specific connection */
     let connection: MCPConnection | undefined;
-    const { user, ...callOptions } = options ?? {};
     const userId = user?.id;
     const logPrefix = userId ? `[MCP][User: ${userId}][${serverName}]` : `[MCP][${serverName}]`;
 
@@ -852,6 +862,7 @@ export class MCPManager {
           oauthStart,
           oauthEnd,
           signal: options?.signal,
+          customUserVars,
         });
       } else {
         /** App-level connection */
@@ -883,7 +894,7 @@ export class MCPManager {
         CallToolResultSchema,
         {
           timeout: connection.timeout,
-          ...callOptions,
+          ...options,
         },
       );
       if (userId) {