MCP-Discord

/** biome-ignore-all lint/style/noNonNullAssertion: <TODO: Fix these later> */ /** biome-ignore-all lint/suspicious/noExplicitAny: <TODO: Fix these later> */ /** biome-ignore-all lint/style/noParameterProperties: <TODO: Fix these later> */ /** biome-ignore-all lint/nursery/noShadow: <TODO: Fix these later> */ /** biome-ignore-all lint/complexity/noExcessiveCognitiveComplexity: <TODO: Fix these later> */ /** biome-ignore-all lint/suspicious/noEvolvingTypes: <TODO: Fix these later> */ /** biome-ignore-all lint/suspicious/noImplicitAnyLet: <TODO: Fix these later> */ /** biome-ignore-all lint/style/useDefaultSwitchClause: <TODO: Fix these later> */ import type { Server } from '@modelcontextprotocol/sdk/server/index.js'; import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'; import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js'; import { Client, GatewayIntentBits } from 'discord.js'; import express, { type Request, type Response } from 'express'; import { error, info } from './logger.js'; import { toolList } from './tool-list.js'; import { addMultipleReactionsHandler, addReactionHandler, createCategoryHandler, createForumPostHandler, createTextChannelHandler, createToolContext, createWebhookHandler, deleteCategoryHandler, deleteChannelHandler, deleteForumPostHandler, deleteMessageHandler, deleteWebhookHandler, editCategoryHandler, editWebhookHandler, getForumChannelsHandler, getForumPostHandler, getServerInfoHandler, loginHandler, readMessagesHandler, removeReactionHandler, replyToForumHandler, sendMessageHandler, sendWebhookMessageHandler, } from './tools/tools.js'; export interface MCPTransport { start(server: Server): Promise<void>; stop(): Promise<void>; } export class StdioTransport implements MCPTransport { private transport: StdioServerTransport | null = null; async start(server: Server): Promise<void> { this.transport = new StdioServerTransport(); await server.connect(this.transport); } async stop(): Promise<void> { if (this.transport) { await this.transport.close(); this.transport = null; } } } export class StreamableHttpTransport implements MCPTransport { private app: express.Application; private server: Server | null = null; private httpServer: any = null; private transport: StreamableHTTPServerTransport | null = null; private toolContext: ReturnType<typeof createToolContext> | null = null; private sessionId = ''; constructor(private port = 8080) { this.app = express(); this.app.use(express.json()); this.setupEndpoints(); this.sessionId = `session_${Date.now()}_${Math.random().toString(36).substring(2, 10)}`; info(`Created HTTP transport with session ID: ${this.sessionId}`); } private setupEndpoints() { // Handler for POST requests this.app.post('/mcp', (req: Request, res: Response) => { info(`Received MCP request: ${JSON.stringify(req.body)}`); this.handleMcpRequest(req, res).catch((error) => { error(`Unhandled error in MCP request: ${String(error)}`); }); }); // Handler for non-POST methods this.app.all('/mcp', (req: Request, res: Response) => { if (req.method !== 'POST') { res.status(405).json({ jsonrpc: '2.0', error: { code: -32_000, message: 'Method not allowed. Use POST.', }, id: null, }); } }); } private async handleMcpRequest(req: Request, res: Response) { try { if (!this.server) { return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Server not initialized', }, id: req.body?.id || null, }); } info( `Request body (session ${this.sessionId}): ${JSON.stringify(req.body)}` ); // Handle all tool requests in a generic way if (!req.body.method) { return res.status(400).json({ jsonrpc: '2.0', error: { code: -32_600, message: 'Invalid Request: No method specified', }, id: req.body?.id || null, }); } // Handle all tools directly with proper error handling try { const method = req.body.method; const params = req.body.params || {}; // Make sure toolContext is available for tool methods if ( !this.toolContext && method !== 'list_tools' && method !== 'initialize' ) { return res.status(400).json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Tool context not initialized. Service may need to be restarted.', }, id: req.body?.id || null, }); } let result; // Handle each tool method directly switch (method) { case 'initialize': // Handle initialize method for MCP protocol compliance result = { protocolVersion: '2025-03-26', capabilities: { tools: { listChanged: false, }, logging: {}, }, serverInfo: { name: 'MCP-Discord', version: '1.2.0', }, }; break; case 'notifications/initialized': // Client indicates it's ready to begin normal operation info('Client initialized. Starting normal operations.'); // No result needed for notifications return res.json({ jsonrpc: '2.0', result: null, id: req.body.id, }); case 'tools/list': // New MCP method name format result = { tools: toolList }; break; case 'list_tools': // Legacy method name for backward compatibility result = { tools: toolList }; break; case 'discord_login': result = await loginHandler(params, this.toolContext!); // Log client state after login info( `Client state after login: ${JSON.stringify({ isReady: this.toolContext?.client.isReady(), hasToken: !!this.toolContext?.client.token, user: this.toolContext?.client.user ? { id: this.toolContext?.client.user.id, tag: this.toolContext?.client.user.tag, } : null, })}` ); break; // Make sure Discord client is logged in for other Discord API tools // but return a proper JSON-RPC error rather than throwing an exception case 'discord_send': case 'discord_get_forum_channels': case 'discord_create_forum_post': case 'discord_get_forum_post': case 'discord_reply_to_forum': case 'discord_delete_forum_post': case 'discord_create_text_channel': case 'discord_delete_channel': case 'discord_read_messages': case 'discord_get_server_info': case 'discord_add_reaction': case 'discord_add_multiple_reactions': case 'discord_remove_reaction': case 'discord_delete_message': case 'discord_create_webhook': case 'discord_send_webhook_message': case 'discord_edit_webhook': case 'discord_delete_webhook': case 'discord_create_category': case 'discord_edit_category': case 'discord_delete_category': // Check if client is logged in if (!this.toolContext?.client.isReady()) { error( `Client not ready for method ${method}, client state: ${JSON.stringify( { isReady: this.toolContext?.client.isReady(), hasToken: !!this.toolContext?.client.token, user: this.toolContext?.client.user ? { id: this.toolContext?.client.user.id, tag: this.toolContext?.client.user.tag, } : null, } )}` ); // Check if we have a token but not ready - try to force reconnect if (this.toolContext?.client.token) { info('Has token but not ready - attempting to force reconnect'); try { // Attempt to force login with existing token await this.toolContext?.client.login( this.toolContext?.client.token ); info( `Force reconnect successful: ${this.toolContext?.client.isReady()}` ); // If still not ready after reconnect, return error if (!this.toolContext?.client.isReady()) { return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Discord client reconnect failed. Please use discord_login tool first.', }, id: req.body?.id || null, }); } // Continue with original request as now logged in info( 'Reconnected successfully, continuing with original request' ); } catch (reconnectError) { error( `Reconnect failed: ${reconnectError instanceof Error ? reconnectError.message : String(reconnectError)}` ); return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Discord client reconnect failed. Please use discord_login tool first.', }, id: req.body?.id || null, }); } } else { return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Discord client not logged in. Please use discord_login tool first.', }, id: req.body?.id || null, }); } } // Call appropriate handler based on method switch (method) { case 'discord_send': result = await sendMessageHandler(params, this.toolContext!); break; case 'discord_get_forum_channels': result = await getForumChannelsHandler( params, this.toolContext! ); break; case 'discord_create_forum_post': result = await createForumPostHandler( params, this.toolContext! ); break; case 'discord_get_forum_post': result = await getForumPostHandler(params, this.toolContext!); break; case 'discord_reply_to_forum': result = await replyToForumHandler(params, this.toolContext!); break; case 'discord_delete_forum_post': result = await deleteForumPostHandler( params, this.toolContext! ); break; case 'discord_create_text_channel': result = await createTextChannelHandler( params, this.toolContext! ); break; case 'discord_delete_channel': result = await deleteChannelHandler(params, this.toolContext!); break; case 'discord_read_messages': result = await readMessagesHandler(params, this.toolContext!); break; case 'discord_get_server_info': result = await getServerInfoHandler(params, this.toolContext!); break; case 'discord_add_reaction': result = await addReactionHandler(params, this.toolContext!); break; case 'discord_add_multiple_reactions': result = await addMultipleReactionsHandler( params, this.toolContext! ); break; case 'discord_remove_reaction': result = await removeReactionHandler(params, this.toolContext!); break; case 'discord_delete_message': result = await deleteMessageHandler(params, this.toolContext!); break; case 'discord_create_webhook': result = await createWebhookHandler(params, this.toolContext!); break; case 'discord_send_webhook_message': result = await sendWebhookMessageHandler( params, this.toolContext! ); break; case 'discord_edit_webhook': result = await editWebhookHandler(params, this.toolContext!); break; case 'discord_delete_webhook': result = await deleteWebhookHandler(params, this.toolContext!); break; case 'discord_create_category': result = await createCategoryHandler(params, this.toolContext!); break; case 'discord_edit_category': result = await editCategoryHandler(params, this.toolContext!); break; case 'discord_delete_category': result = await deleteCategoryHandler(params, this.toolContext!); break; } break; case 'tools/call': { // Handle new tools/call method format const toolName = params.name; const toolArgs = params.arguments || {}; // Check if Discord client is logged in for Discord API tools if ( toolName !== 'discord_login' && toolName.startsWith('discord_') && !this.toolContext?.client.isReady() ) { error( `Client not ready for tool ${toolName}, client state: ${JSON.stringify( { isReady: this.toolContext?.client.isReady(), hasToken: !!this.toolContext?.client.token, user: this.toolContext?.client.user ? { id: this.toolContext?.client.user.id, tag: this.toolContext?.client.user.tag, } : null, } )}` ); // Check if we have a token but not ready - try to force reconnect if (this.toolContext?.client.token) { info('Has token but not ready - attempting to force reconnect'); try { // Attempt to force login with existing token await this.toolContext?.client.login( this.toolContext?.client.token ); info( `Force reconnect successful: ${this.toolContext?.client.isReady()}` ); // If still not ready after reconnect, return error if (!this.toolContext?.client.isReady()) { return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Discord client reconnect failed. Please use discord_login tool first.', }, id: req.body?.id || null, }); } // Continue with original request as now logged in info( 'Reconnected successfully, continuing with original request' ); } catch (reconnectError) { error( `Reconnect failed: ${reconnectError instanceof Error ? reconnectError.message : String(reconnectError)}` ); return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Discord client reconnect failed. Please use discord_login tool first.', }, id: req.body?.id || null, }); } } else { return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: 'Discord client not logged in. Please use discord_login tool first.', }, id: req.body?.id || null, }); } } // Call the appropriate handler based on tool name switch (toolName) { case 'discord_login': result = await loginHandler(toolArgs, this.toolContext!); // Log client state after login info( `Client state after login: ${JSON.stringify({ isReady: this.toolContext?.client.isReady(), hasToken: !!this.toolContext?.client.token, user: this.toolContext?.client.user ? { id: this.toolContext?.client.user.id, tag: this.toolContext?.client.user.tag, } : null, })}` ); break; case 'discord_send': result = await sendMessageHandler(toolArgs, this.toolContext!); break; case 'discord_get_forum_channels': result = await getForumChannelsHandler( toolArgs, this.toolContext! ); break; case 'discord_create_forum_post': result = await createForumPostHandler( toolArgs, this.toolContext! ); break; case 'discord_get_forum_post': result = await getForumPostHandler(toolArgs, this.toolContext!); break; case 'discord_reply_to_forum': result = await replyToForumHandler(toolArgs, this.toolContext!); break; case 'discord_delete_forum_post': result = await deleteForumPostHandler( toolArgs, this.toolContext! ); break; case 'discord_create_text_channel': result = await createTextChannelHandler( toolArgs, this.toolContext! ); break; case 'discord_delete_channel': result = await deleteChannelHandler( toolArgs, this.toolContext! ); break; case 'discord_read_messages': result = await readMessagesHandler(toolArgs, this.toolContext!); break; case 'discord_get_server_info': result = await getServerInfoHandler( toolArgs, this.toolContext! ); break; case 'discord_add_reaction': result = await addReactionHandler(toolArgs, this.toolContext!); break; case 'discord_add_multiple_reactions': result = await addMultipleReactionsHandler( toolArgs, this.toolContext! ); break; case 'discord_remove_reaction': result = await removeReactionHandler( toolArgs, this.toolContext! ); break; case 'discord_delete_message': result = await deleteMessageHandler( toolArgs, this.toolContext! ); break; case 'discord_create_webhook': result = await createWebhookHandler( toolArgs, this.toolContext! ); break; case 'discord_send_webhook_message': result = await sendWebhookMessageHandler( toolArgs, this.toolContext! ); break; case 'discord_edit_webhook': result = await editWebhookHandler(toolArgs, this.toolContext!); break; case 'discord_delete_webhook': result = await deleteWebhookHandler( toolArgs, this.toolContext! ); break; case 'discord_create_category': result = await createCategoryHandler( toolArgs, this.toolContext! ); break; case 'discord_edit_category': result = await editCategoryHandler(toolArgs, this.toolContext!); break; case 'discord_delete_category': result = await deleteCategoryHandler( toolArgs, this.toolContext! ); break; default: return res.status(400).json({ jsonrpc: '2.0', error: { code: -32_601, message: `Unknown tool: ${toolName}`, }, id: req.body?.id || null, }); } break; } default: // For method 'ping' and other non-critical methods, just return an empty result // This ensures MCP compatibility for health checks and probes if (method === 'ping') { info('Returning empty response for ping request'); result = {}; } else { // For other unknown methods, return method not found error return res.status(400).json({ jsonrpc: '2.0', error: { code: -32_601, message: `Method not found: ${method}`, }, id: req.body?.id || null, }); } } info(`Request for ${method} handled successfully`); // Handle the case where tool handlers return { content, isError } if (result && typeof result === 'object' && 'content' in result) { // If it's an error from the tool handler if ('isError' in result && result.isError) { error(`Tool error response: ${JSON.stringify(result)}`); return res.json({ jsonrpc: '2.0', id: req.body.id, error: { code: -32_603, message: Array.isArray(result.content) ? result.content.map((item: any) => item.text).join(' ') : 'Tool execution error', }, }); } // Return success result but maintain same format as other RPC methods const finalResponse = { jsonrpc: '2.0', id: req.body.id, result, }; info( `Sending response (session ${this.sessionId}): ${JSON.stringify(finalResponse)}` ); return res.json(finalResponse); } // Standard result format const finalResponse = { jsonrpc: '2.0', id: req.body.id, result, }; info( `Sending response (session ${this.sessionId}): ${JSON.stringify(finalResponse)}` ); return res.json(finalResponse); } catch (err) { error(`Error processing tool request: ${String(err)}`); // Handle validation errors if ( err && typeof err === 'object' && 'name' in err && err.name === 'ZodError' ) { return res.json({ jsonrpc: '2.0', error: { code: -32_602, message: `Invalid parameters: ${err && typeof err === 'object' && 'message' in err ? String((err as any).message) : 'Unknown validation error'}`, }, id: req.body?.id || null, }); } // Handle all other errors return res.json({ jsonrpc: '2.0', error: { code: -32_603, message: err instanceof Error ? err.message : 'Unknown error', }, id: req.body?.id || null, }); } } catch (err) { error(`Error handling MCP request: ${String(err)}`); if (!res.headersSent) { res.json({ jsonrpc: '2.0', error: { code: -32_603, message: err instanceof Error ? err.message : 'Internal server error', }, id: req.body?.id || null, }); } } } async start(server: Server): Promise<void> { this.server = server; info(`Starting HTTP transport with server: ${String(!!this.server)}`); // Try to get client from the DiscordMCPServer instance // First, check if the server is passed from DiscordMCPServer if (server) { // Try to access client directly from server._context const anyServer = server as any; let client: Client | undefined; if (anyServer._context?.client) { client = anyServer._context.client; info('Found client in server._context'); } // Also check if the server object has client directly else if (anyServer.client instanceof Client) { client = anyServer.client; info('Found client directly on server object'); } // Look in parent object if available else if (anyServer._parent?.client instanceof Client) { client = anyServer._parent.client; info('Found client in server._parent'); } if (client) { this.toolContext = createToolContext(client); info('Tool context initialized with Discord client'); } else { // Create a real Discord client instead of a dummy info('Creating new Discord client for transport'); const newClient = new Client({ intents: [ GatewayIntentBits.Guilds, GatewayIntentBits.GuildMessages, GatewayIntentBits.MessageContent, GatewayIntentBits.GuildMessageReactions, ], }); this.toolContext = createToolContext(newClient); info('Tool context initialized with new Discord client'); } } // Create a stateless transport this.transport = new StreamableHTTPServerTransport({ sessionIdGenerator: undefined, // set to undefined for stateless servers }); // Connect the transport await this.server.connect(this.transport); info('Transport connected'); return new Promise((resolve) => { this.httpServer = this.app.listen(this.port, '0.0.0.0', () => { info(`MCP Server listening on 0.0.0.0:${this.port}`); resolve(); }); }); } async stop(): Promise<void> { if (this.transport) { await this.transport.close(); this.transport = null; } if (this.server) { await this.server.close(); this.server = null; } if (this.httpServer) { return new Promise((resolve) => { this.httpServer.close(() => { info('HTTP server closed'); this.httpServer = null; resolve(); }); }); } } }