next-chat/app/mcp/types.ts

// ref: https://spec.modelcontextprotocol.io/specification/basic/messages/

import { z } from "zod";

export interface McpRequestMessage {
  jsonrpc?: "2.0";
  id?: string | number;
  method: "tools/call" | string;
  params?: {
    [key: string]: unknown;
  };
}

export const McpRequestMessageSchema: z.ZodType<McpRequestMessage> = z.object({
  jsonrpc: z.literal("2.0").optional(),
  id: z.union([z.string(), z.number()]).optional(),
  method: z.string(),
  params: z.record(z.unknown()).optional(),
});

export interface McpResponseMessage {
  jsonrpc?: "2.0";
  id?: string | number;
  result?: {
    [key: string]: unknown;
  };
  error?: {
    code: number;
    message: string;
    data?: unknown;
  };
}

export const McpResponseMessageSchema: z.ZodType<McpResponseMessage> = z.object(
  {
    jsonrpc: z.literal("2.0").optional(),
    id: z.union([z.string(), z.number()]).optional(),
    result: z.record(z.unknown()).optional(),
    error: z
      .object({
        code: z.number(),
        message: z.string(),
        data: z.unknown().optional(),
      })
      .optional(),
  },
);

export interface McpNotifications {
  jsonrpc?: "2.0";
  method: string;
  params?: {
    [key: string]: unknown;
  };
}

export const McpNotificationsSchema: z.ZodType<McpNotifications> = z.object({
  jsonrpc: z.literal("2.0").optional(),
  method: z.string(),
  params: z.record(z.unknown()).optional(),
});