import { type CoreMessage } from "acp-kernel";
export declare function estimateTextTokens(text: string): number;
/** Union of message ids covered by ACTIVE compression blocks. Messages in
 *  this set are already pruned from the sent view — token estimates for the
 *  sent view skip them (their summary mass is counted by the kernel
 *  breakdown as `summaries`). */
export declare function collectCoveredMessageIds(state: {
    blocks: {
        active: boolean;
        effectiveMessageIds: string[];
    }[];
}): Set<string>;
/** Estimate the SENT-VIEW token mass (chars/4, CJK-aware) of a core-message
 *  projection: skips compress tool-calls and messages already covered by
 *  active blocks. This is the same estimation scale as the kernel's
 *  contextBreakdown, so its output can feed nudge decisions and panel lines
 *  without scale mixing. The host footer's session-tree accounting
 *  (provider-anchored, includes compressed originals, never shrinks) is a
 *  DIFFERENT scale and must never drive emergency arbitration for the sent
 *  view — a 180K-context model with a 366K tree reads as "204%" here while
 *  the real sent view is ~5%. */
export declare function estimateTokens(messages: CoreMessage[], coveredIds?: Set<string>): number;
export declare function lastUserMessageId(entries: {
    id: string;
    message?: {
        role?: string;
    };
}[]): string | undefined;
export declare function formatTokens(n: number): string;