import type { Api, Model } from '@earendil-works/pi-ai';
export type PromptCacheChangeReason = 'model_changed' | 'reasoning_changed' | 'system_changed' | 'dynamic_context_changed' | 'tools_changed';
export interface PromptCacheSnapshot {
    modelRef: string;
    api: string;
    reasoning?: string;
    stableSystemDigest: string;
    dynamicSystemDigest: string;
    toolDigest: string;
    toolCount: number;
}
export declare function buildPromptCacheSnapshot(params: {
    model: Model<Api>;
    systemPrompt?: string;
    tools?: unknown[];
    reasoning?: string;
}): PromptCacheSnapshot;
export declare function diffPromptCacheSnapshots(previous: PromptCacheSnapshot | undefined, next: PromptCacheSnapshot): PromptCacheChangeReason[];
export declare function observePromptCacheSnapshot(scope: string, snapshot: PromptCacheSnapshot): PromptCacheChangeReason[];
export declare function clearPromptCacheObservations(): void;