Function jsonRpcErrorBody

packages/hosts/mcp/src/envelope.ts:130–157

(
  status: number,
  code: number,
  message: string,
  opts?: {
    readonly cors?: boolean;
    readonly challenge?: string;
    readonly retryAfterSeconds?: number;
  },
)

 * local — the four hand-rolled copies are deleted in favor of this.
 */
export const jsonRpcErrorBody = (
  status: number,
  code: number,
  message: string,
  opts?: {
    readonly cors?: boolean;
    readonly challenge?: string;
    readonly retryAfterSeconds?: number;
  },
): Response => {
  const cors = opts?.cors ?? true;
  const challenge = opts?.challenge;
  const retryAfterSeconds = opts?.retryAfterSeconds;
  return new Response(JSON.stringify({ jsonrpc: "2.0", error: { code, message }, id: null }), {
    status,
    headers: {
      "content-type": "application/json",
      ...(cors ? { "access-control-allow-origin": "*" } : {}),
      ...(challenge
        ? {
            "www-authenticate": challenge,
            "access-control-expose-headers": "WWW-Authenticate",
          }
        : {}),
      ...(retryAfterSeconds === undefined ? {} : { "retry-after": String(retryAfterSeconds) }),
    },
  });
};

/** Graceful rollback response that lets auto-negotiating v2 clients try legacy. */
export const mcpModernDisabledResponse = (opts?: { readonly cors?: boolean }): Response =>