export interface OAuthListener {
    port: number;
    /** Resolves with the OAuth callback params when /callback is hit. */
    await: Promise<{
        code: string;
        state: string;
    }>;
    close: () => void;
}
/**
 * Start a localhost HTTP server on an ephemeral port that resolves a Promise
 * when the OAuth callback hits `/callback?code=...&state=...`. Responds to the
 * browser with a "You can close this tab" HTML page.
 */
export declare function startOAuthListener(): Promise<OAuthListener>;