@ririaru/mcp-gpt5-server/mcp-gpt5-bridge.js

Enhanced MCP server for GPT-5 with advanced features

#!/usr/bin/env node

// MCP GPT-5 Bridge Server
// This server acts as a bridge between Claude Code MCP and the GPT-5 proxy on Vercel

import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import { z } from 'zod';

const API_URL = 'https://mcpgpt5.vercel.app/api/messages';

// Call GPT-5 API via your enhanced proxy
async function callGPT5(message, level = 'low', verbosity = 'concise') {
  const ctrl = new AbortController();
  const timer = setTimeout(() => ctrl.abort(), 10_000); // 10s タイムアウト

  try {
    const response = await fetch(API_URL, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json',
        'User-Agent': 'gpt5-mcp-bridge/2.1',
      },
      body: JSON.stringify({
        prompt: message,
        level: level,
        verbosity: verbosity
      }),
      signal: ctrl.signal,
    });

    const reqId = response.headers.get('x-req-id') || 'n/a';
    const text = await response.text();

    if (!response.ok) {
      // Vercel の 500 汎用文面（"A server error has occurred" 等）もここに入る
      throw new Error(`API error: ${response.status} - ${text} (x-req-id=${reqId})`);
    }

    let data;
    try { 
      data = JSON.parse(text); 
    } catch { 
      throw new Error(`Non-JSON response: ${text} (x-req-id=${reqId})`); 
    }

    console.error('[sk_gpt5] OK', { reqId, status: response.status, hasContent: !!data.content });
    return data.content?.[0]?.text || data.content || 'No response from GPT-5';
  } catch (error) {
    console.error('[sk_gpt5] ERROR', error.message);
    throw error;
  } finally {
    clearTimeout(timer);
  }
}

// Start the server
async function main() {
  const server = new McpServer({
    name: 'gpt5-proxy',
    version: '2.1.0',
    description: 'Enhanced GPT-5 MCP with reasoning levels, caching, and verbosity control',
  });

  // Register enhanced tool with level and verbosity controls
  server.registerTool(
    'sk_gpt5',
    {
      title: 'Chat with Enhanced GPT-5 via Vercel proxy',
      description: 'Calls GPT-5 through your enhanced Vercel proxy with reasoning levels and verbosity control',
      inputSchema: {
        message: z.string().describe('Message to send to GPT-5'),
        level: z.enum(['low', 'medium', 'high']).optional().describe('Reasoning effort level (default: low)'),
        verbosity: z.enum(['concise', 'normal', 'verbose']).optional().describe('Response verbosity (default: concise)')
      },
    },
    async ({ message, level, verbosity }) => {
      console.error('Calling enhanced sk_gpt5 with:', { message, level, verbosity });
      
      try {
        const responseText = await callGPT5(message, level, verbosity);
        
        return {
          content: [
            {
              type: 'text',
              text: responseText,
            },
          ],
        };
      } catch (error) {
        console.error('Error calling GPT-5:', error);
        return {
          content: [
            {
              type: 'text',
              text: `Error: ${error.message}`,
            },
          ],
        };
      }
    }
  );

  // Connect transport
  const transport = new StdioServerTransport();
  await server.connect(transport);
  
  console.error('GPT-5 MCP Bridge Server started');
}

main().catch((error) => {
  console.error('Failed to start server:', error);
  process.exit(1);
});