/**
 * anthropicCacheWire — the cache↔wire translation both Anthropic adapters share.
 *
 * Pattern: extracted helper (was module-private inside BrowserAnthropicProvider).
 * Role:    Outer ring. Two jobs, one file:
 *   1. `applyCacheMarkers` — stamp `cache_control` onto an Anthropic request
 *      body where the framework's `CacheMarker`s point.
 *   2. `readCacheUsage` — lift Anthropic's cache token counts off a response
 *      usage payload into the port's `cacheRead` / `cacheWrite` fields.
 *
 * Why it exists: the server adapter (`AnthropicProvider`) used to drop
 * `LLMRequest.cacheMarkers` on the floor and report no cache tokens, so on
 * the server path a byte-identical prompt prefix could neither be cached nor
 * even OBSERVED as uncached — `AnthropicCacheStrategy` registers for both
 * `'anthropic'` and `'browser-anthropic'`, and only the browser half kept its
 * side of the contract. One module serving both adapters removes the gap and
 * prevents byte-twin drift between them.
 *
 * @example
 *   const indexMap: number[] = [];
 *   const body = { model, max_tokens, messages: toAnthropicMessages(req.messages, indexMap) };
 *   if (req.cacheMarkers?.length) applyCacheMarkers(body, req.cacheMarkers, indexMap);
 *   // ...and on the way back:
 *   return { usage: { input, output, ...readCacheUsage(message.usage) } };
 */
/**
 * Where each request message ended up in the provider body — `-1` for one
 * that did not survive the transform.
 *
 * This exists because the two arrays are NOT the same length or the same
 * order: a `role: 'system'` message is dropped (system is a separate
 * top-level field) and consecutive `role: 'tool'` messages are coalesced
 * into ONE user turn. A `CacheMarker{field:'messages'}` names a position in
 * `LLMRequest.messages`, so without this map it would be applied by ordinal
 * into a differently-indexed array and land on the wrong turn — silently,
 * and further off the more tool round-trips the conversation has had.
 */
export type MessageIndexMap = readonly number[];
/**
 * The slice of an Anthropic request body that markers touch. Structural on
 * purpose: each adapter keeps its own full body interface, and this module
 * must not become a third place that re-declares the whole wire.
 */
interface MarkableBody {
    system?: unknown;
    tools?: unknown[];
    messages: Array<{
        role: string;
        content: unknown;
    }>;
}
/**
 * Apply `CacheMarker[]` to an Anthropic request body in-place.
 *
 * Per-field positional rules (Anthropic API):
 *   - `system`: convert from `string` → array of text blocks; mark the block
 *     with `cache_control`. The body carries the whole system prompt in ONE
 *     block today, so any system marker caches the whole prompt.
 *   - `tools`: mark the tool at `boundaryIndex` (clamped to last tool).
 *   - `messages`: mark the LAST content block of the LAST message in the
 *     cacheable prefix. Anthropic only honors `cache_control` there.
 *
 * `messageIndexMap` translates the marker's index — a position in
 * `LLMRequest.messages` — into a position in `body.messages`. A message that
 * did not survive the transform (`-1`, a system message) cannot be marked at
 * all; silently marking its neighbour would claim a boundary nobody asked for.
 *
 * Markers arrive already clamped to Anthropic's 4-marker limit by
 * `AnthropicCacheStrategy`, so no enforcement here.
 */
export declare function applyCacheMarkers(body: MarkableBody, markers: readonly {
    field: string;
    boundaryIndex: number;
    ttl: 'short' | 'long';
}[], messageIndexMap?: MessageIndexMap): void;
/**
 * Anthropic reports cache traffic on the response usage object:
 * `cache_read_input_tokens` (prefix served from cache) and
 * `cache_creation_input_tokens` (prefix written to cache this call).
 * Both are ABSENT when the request carried no cache_control.
 */
export interface AnthropicUsageWire {
    readonly cache_read_input_tokens?: number;
    readonly cache_creation_input_tokens?: number;
}
/**
 * Lift Anthropic's cache counts into the port's optional `cacheRead` /
 * `cacheWrite` fields. Absent stays absent — an adapter must never invent a
 * zero for a number the provider did not report (that is the difference
 * between "no cache traffic" and "nobody measured").
 */
export declare function readCacheUsage(usage: AnthropicUsageWire | undefined): {
    cacheRead?: number;
    cacheWrite?: number;
};
export {};
//# sourceMappingURL=anthropicCacheWire.d.ts.map