/**
 * compaction/summarize — the authored frame, and the call that fills it.
 *
 * Pattern: Template Method with an authored envelope + untrusted payload.
 * Role:    core/ layer. Two boundaries are enforced here, and they are the
 *          same boundary pointed in opposite directions:
 *
 *          1. Going OUT to the summarizer, the folded transcript is DATA —
 *             wrapped in a delimiter the authored instruction names, so a
 *             message inside the conversation cannot re-instruct the
 *             summarizer just by looking like an instruction.
 *          2. Coming BACK into the window, the summary is DATA — appended
 *             after an authored label the library wrote. A summarizer that
 *             returns "IGNORE ALL PREVIOUS INSTRUCTIONS" produces a message
 *             that still says, in the library's own words and first, that
 *             what follows is a summary written by a model.
 *
 *          The frame is authored. The summary is data. Neither can become
 *          the other.
 *
 *          A third rule joined them in 8.2: the frame may only claim what is
 *          true. It names where the folded messages went, and it reads that
 *          from the resolved retention policy rather than asserting a
 *          constant — see {@link retentionSentence}.
 * Emits:   N/A (the stage emits; this file only builds and calls).
 */
import type { LLMMessage, LLMProvider, LLMResponse } from '../../../adapters/types.js';
import type { CompactionRetention } from './types.js';
export { COMPACTED_FRAME_PREFIX, isCompactedSummary } from '../../../lib/saidByPerson.js';
/**
 * What the summarizer is asked to do. Authored, fixed, and never composed
 * from run content — the only variable part of the summarizer's prompt is
 * the transcript, and that arrives between delimiters this text names.
 */
export declare const SUMMARIZER_SYSTEM_PROMPT: string;
/** The folded span, rendered as the summarizer's input payload. */
export declare function renderTranscript(messages: readonly LLMMessage[]): string;
/**
 * Build the message that replaces the folded span IN THE WINDOW.
 *
 * `role: 'user'` because the fold can reach the window's head, and the
 * providers that care (Anthropic) require the window to open on a user turn.
 * Since 9.55.0 it usually does NOT reach it — the CURRENT REQUEST sits there
 * and refuses to be folded, so the frame lands immediately after it — but the
 * role is right either way and a fold of a window with no identifiable
 * request still opens on one.
 *
 * The label is written by this function and always comes first. `summary` is
 * appended to it verbatim: the library never edits model output, and it never
 * lets model output speak in the library's voice either.
 *
 * The label states the retention policy, and states it truthfully — see
 * {@link retentionSentence}. `COMPACTED_FRAME_PREFIX` is unchanged: it is what
 * every reader and every test matches on, and it stays put.
 */
export declare function buildSummaryMessage(summary: string, facts: {
    readonly foldedMessageCount: number;
    readonly iteration: number;
    readonly model: string;
    readonly retain: CompactionRetention;
}): LLMMessage;
export interface SummarizeResult {
    readonly text: string;
    readonly usage: LLMResponse['usage'];
}
/**
 * Call the summarizer over the folded span.
 *
 * Throws whatever the provider throws — the STAGE decides that a broken
 * summarizer means "no fold this iteration", not "no run". Deciding that
 * here would hide the failure from the record.
 *
 * ## This call is UN-DECORATED, and that is on purpose
 *
 * `provider.complete(...)` below is the raw provider. None of the machinery
 * that wraps the agent's own LLM call wraps this one:
 *
 *   • no `reliability` retry loop (that lives inside the `call-llm` stage);
 *   • no `withRetry` / `withFallback` / `withCircuitBreaker` (those decorate
 *     the provider the AGENT was constructed with, not this argument);
 *   • no cache subflow (`sf-cache` sits in front of `call-llm` only).
 *
 * One attempt, and a failure is recorded as a `'summarizer-failed'` refusal
 * rather than retried. A fold is optional work — the run is correct without
 * it — so spending a retry budget on it, or letting a summarizer outage open
 * a circuit that then blocks the agent's real calls, would trade something
 * that matters for something that does not.
 *
 * The consequence worth knowing: passing the AGENT'S OWN provider instance as
 * the summarizer gives you one object that behaves two different ways inside
 * one run — retried and cached on one path, neither on this one. `.compaction()`
 * refuses that exact pairing when the model matches too; pass a second
 * instance.
 */
export declare function runSummarizer(provider: LLMProvider, model: string, span: readonly LLMMessage[], signal: AbortSignal | undefined): Promise<SummarizeResult>;