npm-check-updates/build/src/types/VersionResult.d.ts

Find newer versions of dependencies than what your package.json allows

import { Version } from './Version';
/** The result of fetching a version from the package manager, which may include an error. Used to pass errors back up the call chain for better reporting. */
export interface VersionResult {
    version?: Version | null;
    error?: string;
    time?: string;
}