🔧 feat: Initial MCP Support (Tools) (#5015)

* 📝 chore: Add comment to clarify purpose of check_updates.sh script

* feat: mcp package

* feat: add librechat-mcp package and update dependencies

* feat: refactor MCPConnectionSingleton to handle transport initialization and connection management

* feat: change private methods to public in MCPConnectionSingleton for improved accessibility

* feat: filesystem demo

* chore: everything demo and move everything under mcp workspace

* chore: move ts-node to mcp workspace

* feat: mcp examples

* feat: working sse MCP example

* refactor: rename MCPConnectionSingleton to MCPConnection for clarity

* refactor: replace MCPConnectionSingleton with MCPConnection for consistency

* refactor: manager/connections

* refactor: update MCPConnection to use type definitions from mcp types

* refactor: update MCPManager to use winston logger and enhance server initialization

* refactor: share logger between connections and manager

* refactor: add schema definitions and update MCPManager to accept logger parameter

* feat: map available MCP tools

* feat: load manifest tools

* feat: add MCP tools delimiter constant and update plugin key generation

* feat: call MCP tools

* feat: update librechat-data-provider version to 0.7.63 and enhance StdioOptionsSchema with additional properties

* refactor: simplify typing

* chore: update types/packages

* feat: MCP Tool Content parsing

* chore: update dependencies and improve package configurations

* feat: add 'mcp' directory to package and update configurations

* refactor: return CONTENT_AND_ARTIFACT format for MCP callTool

* chore: bump @librechat/agents

* WIP: MCP artifacts

* chore: bump @librechat/agents to v1.8.7

* fix: ensure filename has extension when saving base64 image

* fix: move base64 buffer conversion before filename extension check

* chore: update backend review workflow to install MCP package

* fix: use correct `mime` method

* fix: enhance file metadata with message and tool call IDs in image saving process

* fix: refactor ToolCall component to handle MCP tool calls and improve domain extraction

* fix: update ToolItem component for default isInstalled value and improve localization in ToolSelectDialog

* fix: update ToolItem component to use consistent text color for tool description

* style: add theming to ToolSelectDialog

* fix: improve domain extraction logic in ToolCall component

* refactor: conversation item theming, fix rename UI bug, optimize props, add missing types

* feat: enhance MCP options schema with base options (iconPath to start) and make transport type optional, infer based on other option fields

* fix: improve reconnection logic with parallel init and exponential backoff and enhance transport debug logging

* refactor: improve logging format

* refactor: improve logging of available tools by displaying tool names

* refactor: improve reconnection/connection logic

* feat: add MCP package build process to Dockerfile

* feat: add fallback icon for tools without an image in ToolItem component

* feat: Assistants Support for MCP Tools

* fix(build): configure rollup to use output.dir for dynamic imports

* chore: update @librechat/agents to version 1.8.8 and add @langchain/anthropic dependency

* fix: update CONFIG_VERSION to 1.2.0

api/server/services/MCP.js

@@ -0,0 +1,57 @@
+const { tool } = require('@langchain/core/tools');
+const { Constants: AgentConstants } = require('@librechat/agents');
+const {
+  Constants,
+  convertJsonSchemaToZod,
+  isAssistantsEndpoint,
+} = require('librechat-data-provider');
+const { logger, getMCPManager } = require('~/config');
+
+/**
+ * Creates a general tool for an entire action set.
+ *
+ * @param {Object} params - The parameters for loading action sets.
+ * @param {ServerRequest} params.req - The name of the tool.
+ * @param {string} params.toolKey - The toolKey for the tool.
+ * @param {import('@librechat/agents').Providers | EModelEndpoint} params.provider - The provider for the tool.
+ * @param {string} params.model - The model for the tool.
+ * @returns { Promise<typeof tool | { _call: (toolInput: Object | string) => unknown}> } An object with `_call` method to execute the tool input.
+ */
+async function createMCPTool({ req, toolKey, provider }) {
+  const toolDefinition = req.app.locals.availableTools[toolKey]?.function;
+  if (!toolDefinition) {
+    logger.error(`Tool ${toolKey} not found in available tools`);
+    return null;
+  }
+  /** @type {LCTool} */
+  const { description, parameters } = toolDefinition;
+  const schema = convertJsonSchemaToZod(parameters);
+  const [toolName, serverName] = toolKey.split(Constants.mcp_delimiter);
+  /** @type {(toolInput: Object | string) => Promise<unknown>} */
+  const _call = async (toolInput) => {
+    try {
+      const mcpManager = await getMCPManager();
+      const result = await mcpManager.callTool(serverName, toolName, provider, toolInput);
+      if (isAssistantsEndpoint(provider) && Array.isArray(result)) {
+        return result[0];
+      }
+      return result;
+    } catch (error) {
+      logger.error(`${toolName} MCP server tool call failed`, error);
+      return `${toolName} MCP server tool call failed.`;
+    }
+  };
+
+  const toolInstance = tool(_call, {
+    schema,
+    name: toolKey,
+    description: description || '',
+    responseFormat: AgentConstants.CONTENT_AND_ARTIFACT,
+  });
+  toolInstance.mcp = true;
+  return toolInstance;
+}
+
+module.exports = {
+  createMCPTool,
+};