Vercel MCP Adapter

export type McpEventType = | "SESSION_STARTED" // When a new client session begins (either HTTP or SSE) | "SESSION_ENDED" // When a client session ends (SSE disconnection) | "REQUEST_RECEIVED" // When a request is received from the client | "REQUEST_COMPLETED" // When a request completes | "ERROR"; // When an error occurs during any operation export interface McpEventBase { type: McpEventType; timestamp: number; sessionId?: string; requestId?: string; // To track individual requests within a session } export interface McpSessionEvent extends McpEventBase { type: "SESSION_STARTED" | "SESSION_ENDED"; transport: "SSE" | "HTTP"; clientInfo?: { userAgent?: string; ip?: string; }; } export interface McpRequestEvent extends McpEventBase { type: "REQUEST_RECEIVED" | "REQUEST_COMPLETED"; method: string; parameters?: unknown; result?: unknown; duration?: number; // For REQUEST_COMPLETED events status: "success" | "error"; } export interface McpErrorEvent extends McpEventBase { type: "ERROR"; error: Error | string; context?: string; source: "request" | "session" | "system"; severity: "warning" | "error" | "fatal"; } export type McpEvent = McpSessionEvent | McpRequestEvent | McpErrorEvent; export function createEvent<T extends McpEvent>( event: Omit<T, "timestamp"> ): T { return { ...event, timestamp: Date.now(), } as T; }