#!/usr/bin/env node
const MCP_GATEWAY_URL = process.env.MCP_GATEWAY_URL || 'http://127.0.0.1:4444';
const MCP_JWT_TOKEN = process.env.MCP_JWT_TOKEN;
if (!MCP_JWT_TOKEN) {
console.error('Error: MCP_JWT_TOKEN environment variable is not set.');
process.exit(1);
}
// Import fetch with timeout
let fetch;
try {
fetch = globalThis.fetch;
if (!fetch) {
const nodeFetch = require('node-fetch');
fetch = nodeFetch;
}
} catch (error) {
console.error('Error: Could not load fetch. Please install node-fetch: npm install node-fetch@2');
process.exit(1);
}
// Fetch with timeout
async function fetchWithTimeout(url, options = {}, timeout = 5000) {
const controller = new AbortController();
const timeoutId = setTimeout(() => controller.abort(), timeout);
try {
const response = await fetch(url, {
...options,
signal: controller.signal
});
clearTimeout(timeoutId);
return response;
} catch (error) {
clearTimeout(timeoutId);
throw error;
}
}
// Handle stdin with proper buffering
let messageBuffer = '';
process.stdin.on('data', async (data) => {
messageBuffer += data.toString();
// Split on newlines to handle multiple JSON messages
const lines = messageBuffer.split('\n');
// Keep the last incomplete line in the buffer
messageBuffer = lines.pop() || '';
// Process each complete line
for (const line of lines) {
const input = line.trim();
if (!input) continue;
await processMessage(input);
}
});
async function processMessage(input) {
try {
const message = JSON.parse(input);
if (message.method === 'initialize') {
const response = {
jsonrpc: '2.0',
id: message.id,
result: {
protocolVersion: '2025-06-18',
capabilities: {
tools: { listChanged: true },
resources: { subscribe: true, listChanged: true },
prompts: { listChanged: true }
},
serverInfo: {
name: 'MCP Fast Bridge',
version: '1.0.0'
}
}
};
console.log(JSON.stringify(response));
} else if (message.method === 'notifications/initialized') {
// No response needed for notifications
return;
} else if (message.method === 'prompts/list') {
const response = {
jsonrpc: '2.0',
id: message.id,
result: {
prompts: []
}
};
console.log(JSON.stringify(response));
} else if (message.method === 'resources/list') {
const response = {
jsonrpc: '2.0',
id: message.id,
result: {
resources: []
}
};
console.log(JSON.stringify(response));
} else if (message.method === 'tools/list') {
// Handle tools list with timeout - use general endpoint to get all 7 tools
try {
const response = await fetchWithTimeout(`${MCP_GATEWAY_URL}/tools`, {
method: 'GET',
headers: {
'Authorization': `Bearer ${MCP_JWT_TOKEN}`
}
}, 3000); // 3 second timeout
if (!response.ok) {
throw new Error(`Gateway responded with ${response.status}`);
}
const tools = await response.json();
const mcpTools = tools.map(tool => ({
name: tool.name,
description: tool.description || '',
inputSchema: {
type: 'object',
properties: {},
required: []
}
}));
const result = {
jsonrpc: '2.0',
id: message.id,
result: {
tools: mcpTools
}
};
console.log(JSON.stringify(result));
} catch (error) {
// Return empty tools list on error to avoid blocking
const result = {
jsonrpc: '2.0',
id: message.id,
result: {
tools: []
}
};
console.log(JSON.stringify(result));
}
} else if (message.method === 'tools/call') {
// Handle tool execution with timeout
try {
const toolName = message.params.name;
const toolArgs = message.params.arguments || {};
const response = await fetchWithTimeout(`${MCP_GATEWAY_URL}/tools/${encodeURIComponent(toolName)}/execute`, {
method: 'POST',
headers: {
'Authorization': `Bearer ${MCP_JWT_TOKEN}`,
'Content-Type': 'application/json'
},
body: JSON.stringify(toolArgs)
}, 10000); // 10 second timeout for tool execution
if (!response.ok) {
throw new Error(`Gateway responded with ${response.status}`);
}
const result = await response.json();
const toolResponse = {
jsonrpc: '2.0',
id: message.id,
result: {
content: [
{
type: 'text',
text: typeof result === 'string' ? result : JSON.stringify(result, null, 2)
}
]
}
};
console.log(JSON.stringify(toolResponse));
} catch (error) {
const errorResponse = {
jsonrpc: '2.0',
id: message.id,
error: {
code: -32603,
message: `Tool execution error: ${error.message}`
}
};
console.log(JSON.stringify(errorResponse));
}
} else {
// Handle other methods
const response = {
jsonrpc: '2.0',
id: message.id,
error: {
code: -32601,
message: 'Method not found'
}
};
console.log(JSON.stringify(response));
}
} catch (error) {
const errorResponse = {
jsonrpc: '2.0',
error: {
code: -32700,
message: 'Parse error'
},
id: null
};
console.log(JSON.stringify(errorResponse));
}
}
// Keep the process alive
process.stdin.setEncoding('utf8');
process.stdin.resume();
// Handle process termination
process.on('SIGINT', () => {
process.exit(0);
});
process.on('SIGTERM', () => {
process.exit(0);
});
// Add a periodic heartbeat to keep the connection alive
setInterval(() => {
// Just keep the event loop alive
}, 30000);
