/**
 * Redact sensitive substrings from tool responses before they leave the
 * MCP boundary.
 *
 * Tool outputs frequently include filesystem paths (with the user's home
 * directory in them), token-shaped strings, hostnames, IP addresses, and
 * bundle identifiers. None of those are useful to an AI agent reasoning
 * about an iOS leak, and all of them are footguns when the output ends
 * up in a Slack message, a PR comment, or a screenshot. This module
 * scrubs them at the formatter boundary so by-default outputs are safe
 * to share without manual sweeping.
 *
 * Three modes are selected via the `MEMORYDETECTIVE_REDACTION` env var:
 *
 * - `balanced` (default): home-directory absolute paths become `~/...`,
 *   common secret-shaped tokens (AWS keys, GitHub PATs, Stripe secrets,
 *   Slack tokens, Bearer auth) are masked. Hostnames, IPs, bundle IDs,
 *   process names, and class names are preserved (they are usually
 *   useful for debugging).
 *
 * - `strict`: everything in `balanced`, plus hostnames, IPv4 addresses,
 *   and bundle identifiers. Use when the output is going to be pasted
 *   into a public artifact (issue tracker, blog post, social) and you
 *   want a wide safety margin.
 *
 * - `off`: no redaction. Default behavior is preserved for legacy
 *   workflows and for local-only debugging where the noise is genuinely
 *   helpful. The startup banner logs the active mode so an operator
 *   running `off` knows the responses are unfiltered.
 *
 * Redaction is structural: the value passed in keeps its shape (same
 * object keys, same array lengths, same scalar types), only string
 * leaves are rewritten. Numbers, booleans, null/undefined, and dates
 * pass through unchanged.
 */
export type RedactionMode = "balanced" | "strict" | "off";
/**
 * Pure: read the active redaction mode from an env-like object.
 * Defaults to `balanced` when unset or set to an unrecognized value.
 *
 * Threaded as a parameter for testability; production callers omit it
 * and get `process.env`.
 */
export declare function getRedactionMode(env?: Readonly<Record<string, string | undefined>>): RedactionMode;
/**
 * Pure: scrub a single string per the active mode. `off` returns the
 * input unchanged; the other modes apply the rules described in the
 * module doc.
 *
 * Threaded `homeDir` for testability so unit tests can pass a fake
 * `/Users/test/` without depending on the real home directory.
 */
export declare function redactString(input: string, mode: RedactionMode, homeDir?: string): string;
/**
 * Pure: recursively redact strings inside an arbitrary JSON-shaped
 * value. Object key names are preserved unchanged (they are part of
 * the schema, not data); only string VALUES and string ARRAY items
 * are scrubbed.
 *
 * Non-string scalars (number, boolean, null) pass through. Functions,
 * symbols, and other non-JSON values are returned as-is.
 */
export declare function redact(value: unknown, mode: RedactionMode, homeDir?: string): unknown;
export declare function maybeLogRedactionModeOnce(mode: RedactionMode, writer?: (line: string) => void): void;
/** Test-only: reset the once-per-instance log flag. */
export declare function resetRedactionAdvisoryFlagForTests(): void;