import { type GthTerminationReason } from '#src/core/terminationReason.js';
/** The middleware's name, which `createAgent` also gives to the error it wraps a throw in. */
export declare const CUT_STREAM_RETRY_MIDDLEWARE_NAME = "GthCutStreamRetry";
/** The debug-log line written when a cut reply is retried. Stable, so a log can be counted. */
export declare const CUT_STREAM_RETRY_LOG = "EXT-204 cut stream: retrying the model call once";
/** The debug-log line written when the retried reply was cut as well. */
export declare const CUT_STREAM_EXHAUSTED_LOG = "EXT-204 cut stream: the retry was cut too, ending the turn";
/** The debug-log line written when the retry came back whole. */
export declare const CUT_STREAM_RECOVERED_LOG = "EXT-204 cut stream: recovered on the retry";
/**
 * Was this model reply cut off before it finished? True only for an `AIMessage` with no answer text,
 * no tool call (valid or invalid) and no stop/finish reason under any key the EXT-159 reader knows.
 *
 * Thought parts do not count as answer text ({@link answerTextOf} excludes them), which is exactly the
 * measured shape. Anything that is not an `AIMessage` — a `Command` from a structured-output retry —
 * is not a reply this module has an opinion about.
 */
export declare function isCutModelReply(message: unknown): boolean;
/**
 * The model's reply was cut off twice in a row: the turn ends here with the `stream_cut` reason
 * attached, rather than as an empty answer.
 */
export declare class ModelStreamCutError extends Error {
    readonly reason: GthTerminationReason;
    constructor(reason: GthTerminationReason);
}
/**
 * Build the retry middleware. See the module comment for the argument.
 *
 * @param onCut Records the `stream_cut` reason on the agent when the retry is cut as well. Called
 *   before the throw, so the agent's first-write-wins record holds it whatever a later site notes.
 */
export declare function createCutStreamRetryMiddleware(onCut?: (reason: GthTerminationReason) => void): import("langchain").AgentMiddleware<undefined, undefined, unknown, readonly (import("@langchain/core/tools").ServerTool | import("@langchain/core/tools").ClientTool)[], readonly []>;