#!/usr/bin/env node
import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import { VapiClient } from '@vapi-ai/server-sdk';
import { hasValidToken, getToken, startAuthFlow, isAuthInProgress, getAuthUrl, clearConfig } from './auth.js';
import { registerAllTools } from './tools/index.js';
import dotenv from 'dotenv';
dotenv.config();
// Lazy-initialized Vapi client
let vapiClient: VapiClient | null = null;
function getVapiClient(): VapiClient {
const token = getToken();
if (!token) {
throw new Error('Not authenticated');
}
// Reset client if token changed
if (!vapiClient) {
vapiClient = new VapiClient({ token });
}
return vapiClient;
}
function createMcpServer() {
const mcpServer = new McpServer({
name: 'Vapi MCP',
version: '0.1.0',
capabilities: [],
});
// Register the login tool - always available
mcpServer.tool(
'vapi_login',
'Authenticate with Vapi. Call this first if other tools return authentication errors.',
{},
async () => {
// Check if we have a token and validate it
if (hasValidToken()) {
try {
const client = getVapiClient();
await client.assistants.list({ limit: 1 });
return {
content: [
{
type: 'text' as const,
text: 'Already authenticated with Vapi! You can now use other Vapi tools.',
},
],
};
} catch {
// Token is stale — clear it and restart auth
clearConfig();
vapiClient = null;
}
}
// Check if auth is already in progress
if (isAuthInProgress()) {
const url = getAuthUrl();
return {
content: [
{
type: 'text' as const,
text: `Authentication in progress. Please complete sign-in:\n\n${url}\n\nAfter signing in, try your request again.`,
},
],
};
}
// Start auth flow
try {
const authUrl = await startAuthFlow();
return {
content: [
{
type: 'text' as const,
text: `Please sign in to Vapi:\n\n${authUrl}\n\nAfter signing in, try your request again.`,
},
],
};
} catch (error: any) {
return {
content: [
{
type: 'text' as const,
text: `Failed to start authentication: ${error.message}`,
},
],
isError: true,
};
}
}
);
// Register logout tool
mcpServer.tool(
'vapi_logout',
'Log out of Vapi and clear stored credentials. Use this if your auth token is stale or you want to switch accounts.',
{},
async () => {
clearConfig();
vapiClient = null;
return {
content: [
{
type: 'text' as const,
text: 'Logged out of Vapi. Use vapi_login to sign in again.',
},
],
};
}
);
// Register all Vapi tools - they will check auth via createToolHandler
// We use a proxy that creates the client lazily
const clientProxy = new Proxy({} as VapiClient, {
get(_, prop) {
return getVapiClient()[prop as keyof VapiClient];
},
});
registerAllTools(mcpServer, clientProxy);
return mcpServer;
}
async function main() {
try {
const mcpServer = createMcpServer();
const transport = new StdioServerTransport();
await mcpServer.connect(transport);
setupShutdownHandler(mcpServer);
} catch (err) {
console.error('Failed to start MCP server:', err);
process.exit(1);
}
}
function setupShutdownHandler(mcpServer: McpServer) {
process.on('SIGINT', async () => {
try {
await mcpServer.close();
process.exit(0);
} catch (err) {
process.exit(1);
}
});
}
main().catch((err) => {
console.error('Fatal error:', err);
process.exit(1);
});
export { createMcpServer };
