/**
 * The refusal the streaming builder raises, in a module of its own.
 *
 * It used to live in `stream-build.ts`, which is where it is thrown from — but
 * `stream-refusals.ts` throws it too, and importing it back out of the file
 * that imports the refusals would close a cycle. A two-line module breaks it,
 * and `stream-build.ts` re-exports the class so every existing importer keeps
 * working.
 */
/** A feature the streaming builder can't do lazily — Engine 3 catches this to fall back. */
export declare class StreamUnsupportedError extends Error {
    constructor(message: string);
}
/**
 * The refusal both throwers phrase the same way: what it is, and what to do.
 *
 * It lived in `stream-build.ts` beside its callers until `stream-refusals.ts`
 * needed it as well, and importing it back out of the file that imports the
 * refusals would close the very cycle this module exists to break.
 */
export declare function unsupported(feature: string, name: string): StreamUnsupportedError;
//# sourceMappingURL=stream-errors.d.ts.map