import type { AgentMiddleware } from '../create-agent.js';
/** The personal data and secrets `piiMiddleware()` finds on its own. */
export type PiiKind = 'email' | 'credit-card' | 'ssn' | 'phone' | 'iban' | 'ip-address' | 'secret';
/**
 * What happens to a match: `redact` replaces it with its kind, `mask` keeps its last four
 * characters, `hash` replaces it with a stable token so two values stay distinguishable, and `block`
 * refuses the whole message.
 */
export type PiiStrategy = 'redact' | 'mask' | 'hash' | 'block';
/** Where a match was found. */
export type PiiWhere = 'input' | 'output' | 'tool';
/** One match, as `onDetect` sees it: never the value itself. */
export interface PiiFinding {
    /** Its kind: a built-in kind or a name from `patterns`. */
    kind: string;
    /** Where it was found. */
    where: PiiWhere;
    /** What was done with it. */
    strategy: PiiStrategy;
}
/** Options for `piiMiddleware()`. */
export interface PiiMiddlewareOptions {
    /** The built-in kinds to find. Defaults to all of them. */
    kinds?: readonly PiiKind[];
    /** Kinds of your own, by name: `{ 'employee-id': /\bEMP-\d{6}\b/ }`. */
    patterns?: Readonly<Record<string, RegExp>>;
    /**
     * What happens to a match, for every kind or per kind: `'mask'`, or
     * `{ email: 'hash', 'credit-card': 'block' }`. Kinds not named are redacted.
     */
    strategy?: PiiStrategy | Readonly<Record<string, PiiStrategy>>;
    /**
     * Where to look. `input` is every message sent to the model but the system prompt; `output` is
     * the model's answer; `toolResults` cleans a result before it enters the transcript, so it is never
     * checkpointed either. Defaults to input and tool results.
     */
    apply?: {
        input?: boolean;
        output?: boolean;
        toolResults?: boolean;
    };
    /** Called for each match, for an audit trail. */
    onDetect?: (finding: PiiFinding) => void;
}
/** Thrown when a match under the `block` strategy is found in the model's input or output. */
export declare class PiiBlockedError extends Error {
    /** The kind that was found. */
    readonly kind: string;
    /** Where it was found. */
    readonly where: PiiWhere;
    /** Always `PII_BLOCKED`. */
    readonly code = "PII_BLOCKED";
    constructor(
    /** The kind that was found. */
    kind: string, 
    /** Where it was found. */
    where: PiiWhere);
}
/**
 * Keeps personal data and secrets away from the model, the transcript, or both.
 *
 * Finds emails, card numbers (checked with Luhn), US social security numbers, phone numbers, IBANs
 * (checked with their checksum), IP addresses, and common API keys and private keys, plus any kinds
 * of your own; and redacts, masks, hashes, or blocks each. The validated kinds keep false positives
 * low: an order number is not a card number unless its checksum says so.
 */
export declare function piiMiddleware(options?: PiiMiddlewareOptions): AgentMiddleware;