/**
 * Mutation keys contributed by the username plugin.
 *
 * `signIn` is kept under the shared `["auth", "signIn", ...]` namespace so
 * consumers can match the whole sign-in surface with
 * `useIsMutating({ mutationKey: ["auth", "signIn"] })`.
 */
export declare const usernameMutationKeys: {
    /** Key for `signIn.username`. */
    readonly signIn: readonly ["auth", "signIn", "username"];
    /**
     * Key for `isUsernameAvailable`. This is technically a read, but it's
     * exposed via better-auth's mutation surface and lives under the mutation
     * factories for parity with other username flows.
     */
    readonly isUsernameAvailable: readonly ["auth", "isUsernameAvailable"];
};