/**
 * Language-model response cache, as a Vercel AI SDK middleware.
 *
 * Changelog generation is highly repetitive across runs: previewing with
 * `--dry-run` and then generating for real, re-running after a failed provider
 * call, or regenerating the same release, all re-send byte-identical prompts for
 * commits whose diffs have not changed. Caching on the model boundary removes
 * that repeat cost without any call site having to know about it.
 *
 * Key: SHA-256 over the model identity plus the RESPONSE-AFFECTING call
 * parameters only (see `responseAffectingParams`). Transport/runtime fields
 * (`abortSignal`, `headers`) are deliberately excluded — they vary per call and
 * would defeat the cache entirely without changing what the model returns.
 *
 * Storage is a small in-memory LRU in front of a JSON-file cache under the
 * user's cache directory, so hits survive across CLI invocations (the case that
 * actually matters here — a single run rarely repeats a prompt).
 *
 * Every failure path falls OPEN: a cache problem returns the freshly generated
 * result rather than turning a working generation into an error. Streaming
 * (`wrapStream`) is intentionally not cached — this package never streams model
 * output into a changelog.
 */
import type { LanguageModelMiddleware } from 'ai';
export declare function defaultCacheDirectory(): string;
/**
 * Opt-out via AI_CACHE_ENABLED=false. Caching is on by default because a stale
 * entry can only occur for a byte-identical prompt to the same model, which by
 * construction would have produced an equivalent answer.
 */
export declare function isModelCacheEnabled(): boolean;
/**
 * Deterministic serialization: plain JSON.stringify is key-order dependent, so
 * two structurally identical parameter objects could hash differently and miss.
 */
export declare function stableStringify(value: unknown): string;
/**
 * The subset of call parameters that can change what the model returns.
 * Anything omitted here is transport or bookkeeping.
 */
export declare function responseAffectingParams(params: Record<string, any>): {
    prompt: any;
    maxOutputTokens: any;
    temperature: any;
    stopSequences: any;
    topP: any;
    topK: any;
    presencePenalty: any;
    frequencyPenalty: any;
    responseFormat: any;
    seed: any;
    tools: any;
    toolChoice: any;
    providerOptions: any;
};
export declare function fingerprint(model: Record<string, any>, params: Record<string, any>): string;
export interface ModelCacheOptions {
    ttlSeconds?: number;
    cacheDir?: string;
    /** Reported on a hit so callers can surface cache usage. */
    onHit?: (key: string) => void;
    onMiss?: (key: string) => void;
}
export declare function createModelCacheMiddleware(options?: ModelCacheOptions): LanguageModelMiddleware;
/** Exposed for tests: drops the in-process layer without touching disk. */
export declare function clearModelCacheMemory(): void;