1  export class EasyShellError extends Error {
  2    public readonly statusCode: number;
  3    public readonly code: string;
  4  
  5    public constructor(message: string, statusCode: number, code: string) {
  6      super(message);
  7      this.name = "EasyShellError";
  8      this.statusCode = statusCode;
  9      this.code = code;
 10    }
 11  }
 12  
 13  type HttpBody = {
 14    message?: unknown;
 15  };
 16  
 17  function getMessageFromBody(body: unknown, fallback: string): string {
 18    if (typeof body === "object" && body !== null) {
 19      const candidate = (body as HttpBody).message;
 20      if (typeof candidate === "string" && candidate.trim().length > 0) {
 21        return candidate;
 22      }
 23    }
 24  
 25    return fallback;
 26  }
 27  
 28  export function mapHttpError(status: number, body: unknown): EasyShellError {
 29    if (status === 401) {
 30      return new EasyShellError(
 31        getMessageFromBody(body, "Authentication expired. Please verify credentials and retry."),
 32        status,
 33        "AUTH_EXPIRED",
 34      );
 35    }
 36  
 37    if (status === 403) {
 38      return new EasyShellError(
 39        getMessageFromBody(body, "Forbidden. You do not have permission for this operation."),
 40        status,
 41        "FORBIDDEN",
 42      );
 43    }
 44  
 45    if (status === 404) {
 46      return new EasyShellError(
 47        getMessageFromBody(body, "Resource not found."),
 48        status,
 49        "NOT_FOUND",
 50      );
 51    }
 52  
 53    if (status === 449) {
 54      return new EasyShellError(
 55        getMessageFromBody(body, "Operation requires approval before execution."),
 56        status,
 57        "APPROVAL_REQUIRED",
 58      );
 59    }
 60  
 61    if (status >= 500) {
 62      return new EasyShellError(
 63        getMessageFromBody(body, "EasyShell server error. Please retry later."),
 64        status,
 65        "SERVER_ERROR",
 66      );
 67    }
 68  
 69    return new EasyShellError(
 70      getMessageFromBody(body, `HTTP ${status} request failed.`),
 71      status,
 72      "HTTP_ERROR",
 73    );
 74  }
 75  
 76  export function toMcpError(error: unknown): {
 77    content: Array<{ type: "text"; text: string }>;
 78    isError: true;
 79  } {
 80    if (error instanceof EasyShellError) {
 81      return {
 82        content: [
 83          {
 84            type: "text",
 85            text: `[${error.code}] ${error.message}`,
 86          },
 87        ],
 88        isError: true,
 89      };
 90    }
 91  
 92    if (error instanceof Error) {
 93      return {
 94        content: [
 95          {
 96            type: "text",
 97            text: error.message,
 98          },
 99        ],
100        isError: true,
101      };
102    }
103  
104    return {
105      content: [
106        {
107          type: "text",
108          text: "Unknown error occurred.",
109        },
110      ],
111      isError: true,
112    };
113  }