import type { StreamNoOutputSentinel, StreamNoOutputSentinelResultLike } from "../types/index.js";
export declare function buildNoOutputSentinel(error: unknown, result?: StreamNoOutputSentinelResultLike, 
/**
 * Reviewer follow-up: AI SDK v6 wraps the AI SDK's
 * `NoOutputGeneratedError` without preserving the underlying provider
 * error in `error.cause`, and rejects `result.finishReason` /
 * `result.totalUsage` with the wrapped error too. To differentiate
 * content-filter / stop-sequence / provider-crash, providers can
 * capture the upstream error (e.g. via streamText's `onError`
 * callback) and pass it here. When provided, it takes precedence
 * over the AI SDK error for `providerError` and `modelResponseRaw`.
 */
underlyingError?: unknown): Promise<StreamNoOutputSentinel>;
/**
 * Curator P3-6 (round-2): the AI SDK v6 path that sets
 * `NoOutputGeneratedError` does NOT throw it from `result.textStream`
 * iteration — it sets the error as a *promise rejection* on
 * `result.finishReason` / `result.totalUsage` / `result.steps` (see
 * `ai/src/generate-text/stream-text.ts` ~L1078). Providers that only
 * catch errors thrown from `for await (chunk of result.textStream)` will
 * miss the production trigger entirely: the stream completes silently
 * with 0 chunks and the rejection bubbles as an unhandled rejection.
 *
 * This helper surfaces the rejection by awaiting `result.finishReason`
 * after the stream completes. Providers must call this AFTER iterating
 * the textStream when 0 chunks were yielded — the returned sentinel
 * (if non-null) carries the enriched metadata Curator's report needed.
 */
export declare function detectPostStreamNoOutput(result: StreamNoOutputSentinelResultLike, 
/**
 * Optional provider-captured underlying error (e.g. from streamText's
 * `onError` callback). When provided, the resulting sentinel will carry
 * the real provider error in `providerError` / `modelResponseRaw`
 * instead of the AI SDK's generic "No output generated" message.
 */
underlyingError?: unknown): Promise<{
    sentinel: StreamNoOutputSentinel;
    error: Error;
} | null>;
/**
 * Marks the active span as a no-output stream so Langfuse shows a WARNING
 * observation with the enriched status message. Safe to call when tracing
 * isn't initialized — silently no-ops.
 */
export declare function stampNoOutputSpan(sentinel: StreamNoOutputSentinel): void;
/**
 * Build the OTel `langfuse.observation.status_message` summary string for a no-output
 * stream. Used by `StreamHandler.createTextStream` and any future provider
 * that wants to stamp the active span with the same enriched message.
 *
 * Reviewer follow-up: AI SDK v4 used `promptTokens` / `completionTokens`,
 * v6 uses `inputTokens` / `outputTokens`. Read both shapes so the message
 * is correct whichever version surfaced partial usage data.
 */
export declare function buildNoOutputStatusMessage(finishReason: unknown, usage: unknown): string;