export type TraceCoverageGapKind = "missing_trace" | "empty_changes" | "missing_verification" | "binding_mismatch" | "digest_stale" | "missing_run" | "run_not_passed";
export interface TraceCoverageGap {
    requirement_id: string;
    /** missing_trace 时为 null */
    trace_id: string | null;
    kind: TraceCoverageGapKind;
    detail: string;
}
export interface TraceCoverageReport {
    task_id: string;
    requirement_count: number;
    gaps: TraceCoverageGap[];
    /** 覆盖完整:gaps 为空(所有 requirement 有 trace + trace 完整 + run binding/digest 一致)。deliver 据此阻断(后续阶段)。 */
    covered: boolean;
}
export declare class TraceCoverageChecker {
    private readonly requirements;
    private readonly traces;
    private readonly runs;
    constructor(projectRoot: string);
    /** 检查 task 的实现追踪覆盖。无 requirement 的 task 返 requirement_count=0 + covered=true(不强制 requirement,与 RequirementCoverageChecker 同设计)。 */
    check(taskId: string): Promise<TraceCoverageReport>;
}