/**
 * Symbol for attaching failure reason metadata to results without polluting public API.
 * Enables telemetry decorator to track failure reasons without exposing them to users.
 */
export declare const FAILURE_REASON: unique symbol;
/** Internal tracking for telemetry events (not in public result types) */
export type MutationReason = "expired" | "not-found";
/**
 * Internal state taxonomy mapping backend observations to user-facing reasons.
 * DO NOT export in public API - used only by telemetry/mapping layers.
 */
export type MutationCondition = "succeeded"
/** Expiry observed deterministically before mutation */
 | "observable-expired"
/** No record found in storage */
 | "never-existed"
/** Record exists but lockId mismatch */
 | "ownership-mismatch"
/** Auto-removed due to expiry */
 | "cleaned-up-after-expiry"
/** Clock skew, snapshot race, stale index, etc. */
 | "ambiguous-unknown";
export type MutationResult = {
    ok: true;
} | {
    ok: false;
    reason: MutationReason;
};
/**
 * Maps internal backend conditions to public API results.
 * Conservative strategy: collapses ambiguous states to "not-found" for safety.
 */
export declare function mapToMutationResult(cond: MutationCondition): MutationResult;
/**
 * Decodes Redis Lua script return codes to MutationCondition.
 * @param code - Script result: 1=success, 0=ownership mismatch, -1=not found, -2=expired
 * @see redis/scripts.ts
 */
export declare function mapRedisScriptResult(code: number): MutationCondition;
/**
 * Maps Firestore transaction/query observations to MutationCondition.
 * @param conditions - Query result analysis
 * @param conditions.documentExists - !querySnapshot.empty
 * @param conditions.ownershipValid - data?.lockId === lockId
 * @param conditions.isLive - Computed via time authority + tolerance
 * @see common/time-predicates.ts
 */
export declare function mapFirestoreConditions(conditions: {
    /** Document found in query result */
    documentExists: boolean;
    /** Stored lockId matches request */
    ownershipValid: boolean;
    /** Lock not expired per time authority */
    isLive: boolean;
}): MutationCondition;
/**
 * Unified backend observation mapper for Redis codes or Firestore conditions.
 * @param observation - Redis script code or Firestore query analysis
 * @see docs/specs/interface.md
 */
export declare function mapBackendObservation(observation: number | {
    documentExists: boolean;
    ownershipValid: boolean;
    isLive: boolean;
}): MutationCondition;