/** Pure: deterministic absolute path for the keystore file. */
export declare function lighterKeystorePath(accountIndex: number, slot: number): string;
/**
 * Encrypt a 40-byte Lighter L2 private key (hex) and write it to
 * `~/.perp/lighter-agents/<accountIndex>-<slot>.json` with mode 0600.
 *
 * Returns the absolute path of the written file.
 */
export declare function saveLighterKey(accountIndex: number, slot: number, privateKeyHex: string, passphrase: string): string;
/**
 * Read + decrypt a stored Lighter L2 private key. Returns the hex string
 * without `0x` prefix.
 *
 * Throws (no fallback):
 *   - LIGHTER_KEYSTORE_NOT_FOUND if the file is missing
 *   - LIGHTER_KEYSTORE_DECRYPT_FAILED if the passphrase is wrong / file corrupt
 */
export declare function loadLighterKey(accountIndex: number, slot: number, passphrase: string): string;
/**
 * Idempotent delete. Returns true if a file was removed, false if absent.
 */
export declare function deleteLighterKey(accountIndex: number, slot: number): boolean;
/**
 * One-time bridge from legacy env-based storage to the keystore.
 *
 * Triggered on a single, narrow condition: env has `LIGHTER_API_KEY` AND the
 * target keystore file does not yet exist. After successful save, clears the
 * three legacy env entries from `~/.perp/.env` so they cannot be re-read.
 *
 * NOT a fallback (SSOT Rule #2): runs at most once per install (post-clear, the
 * trigger condition is permanently false). Single-direction (env → keystore);
 * never reads from keystore back to env.
 */
export declare function migrateFromEnvIfPresent(): void;