/**
 * MCP call records at rest (DES-MCP-TOOLS-001 §5, D-3): `<state home>/mcp/calls.ndjson`, one OTel
 * span-shaped record per brokered call. Arguments and results are never captured.
 *
 * The broker writes a record for every call it judged, whatever the outcome, and a call whose
 * record cannot be written is refused (`guard_error`): its result is withheld. Appends are
 * serialized on one promise chain so two concurrent calls never interleave a line.
 *
 * The usage slice (S7) reads the records back on the same chain. A read first folds every record
 * that started more than {@link MCP_CALLS_RAW_DAYS} days ago into `calls-daily.ndjson` (one row per
 * UTC day × subject × seat × decision: calls, errors, total ms) and rewrites `calls.ndjson` without
 * them (write a temp file, then rename). The fold runs on demand, never on a timer.
 */
import type { McpCallDecision, McpCallRecord } from '../core/types.js';
export declare const MCP_CALLS_FILENAME = "calls.ndjson";
export declare const MCP_CALLS_DAILY_FILENAME = "calls-daily.ndjson";
/** Records stay raw this long; older ones are folded into the daily file. */
export declare const MCP_CALLS_RAW_DAYS = 30;
export interface McpCallRecordSink {
    append(record: McpCallRecord): Promise<void>;
}
/** One row of `calls-daily.ndjson`. */
export interface McpCallDailyRow {
    day: string;
    subject: string;
    seat: string | null;
    decision: McpCallDecision;
    calls: number;
    errors: number;
    msTotal: number;
}
export interface McpCallRecordsRead {
    records: McpCallRecord[];
    /** Lines that did not parse as a call record (kept in the file, left out of every fold). */
    skipped: number;
    /** Records this read folded into the daily file. */
    folded: number;
}
/** The records the usage fold reads. */
export interface McpCallRecordSource {
    read(now: number): Promise<McpCallRecordsRead>;
}
/** A parsed line when it has the fields the usage fold reads; otherwise `null`. */
export declare function parseCallRecord(line: string): McpCallRecord | null;
/** Fold records into daily rows, sorted by day, subject, seat, decision. */
export declare function foldDaily(records: readonly McpCallRecord[]): McpCallDailyRow[];
export declare class McpCallRecordFile implements McpCallRecordSink, McpCallRecordSource {
    private readonly dir;
    private tail;
    constructor(dir?: string);
    get path(): string;
    get dailyPath(): string;
    append(record: McpCallRecord): Promise<void>;
    /**
     * Every record of the last {@link MCP_CALLS_RAW_DAYS} days, after folding older ones into the
     * daily file. Serialized with the appends, so no call's line is lost to the rewrite.
     */
    read(now: number): Promise<McpCallRecordsRead>;
    private serialize;
}
//# sourceMappingURL=call-records.d.ts.map