/**
 * Conservative stripping for a message-opening `<think>…</think>` block.
 *
 * Only translated OpenAI text is routed through this module. Native Anthropic thinking blocks
 * and byte-exact OpenAI Chat passthrough never reach it. The filter strips at most one complete,
 * unnested block; every uncertain shape is released byte-for-byte as ordinary text.
 */
export declare const MAX_THINK_LEAD_BYTES = 512;
export declare const MAX_THINK_HELD_BYTES: number;
/**
 * Four-state text filter shared by buffered and streaming translation.
 *
 * `inside-think` retains the candidate block until its close is proven. That bounded rollback
 * buffer is what makes an unclosed or nested block lossless instead of silently deleting text.
 */
export declare class ThinkTagStripFilter {
    private state;
    private held;
    private bodyStart;
    private scanFrom;
    push(text: string): string;
    /**
     * Release every undecided byte when the message/text block ends.
     *
     * A table, not an `if`/`else`: this filter's whole purpose is losslessness, so a future state
     * that HOLDS bytes must be a compile error here rather than falling into the empty return and
     * silently deleting them. `done` and `pass-through` return empty because both have already
     * released and cleared their held text.
     */
    flush(): string;
    private decideLead;
    private inspectThink;
    private releaseLosslessly;
}
/** Strip one complete opening block, or return the original text on any doubt. */
export declare function stripOpeningThinkTag(text: string): string;
/**
 * Rewrite translated Anthropic SSE text deltas through the strip filter. All non-text frames pass
 * through; held doubtful text is emitted before its content block closes, preserving SSE order.
 */
export declare function stripThinkTagsInStream(upstream: ReadableStream<Uint8Array>): ReadableStream<Uint8Array>;