/**
 * Whether a rejected SDK call ran out its own per-call timeout. The timeout
 * `composeSdkAbortSignal` adds rejects with the SDK's `AbortError`, exactly
 * as the caller's cancel does, so only the caller's signal tells them apart:
 * an `AbortError` the caller did not raise is the timeout.
 *
 * That rests on a premise about the SDK, measured on main on 2026-09-29
 * against `@aws-sdk/client-cloudformation` 3.1101.0 (range `^3.1098.0`),
 * whose sends go through `@smithy/node-http-handler` 4.9.13, the versions
 * this line's lockfile holds: a send rejects with an error named
 * `AbortError` only when the signal it was sent under aborts
 * (`buildAbortError` there). `@smithy/core` raises one other `AbortError`,
 * from a waiter, which no send reaches. The caller's signal is read when the
 * rejection is classified, so a cancel that lands after the timeout reads as
 * the cancel. The verdict picks only a failure's wording and retry class,
 * and must never authorise anything.
 */
export declare function isPerCallTimeout(error: unknown, abortSignal: AbortSignal | undefined): boolean;
/**
 * A rejected SDK call's reason, for a sentence that already names the call:
 * a per-call timeout by its budget, never the SDK's `AbortError` text, which
 * reads as the operator's cancel; any other failure as the SDK words it.
 * Pre-masked at construction: the timeout names only the budget, and any
 * other reason is `maskSensitiveOutput(getErrorMessage(error))`.
 */
export declare function sdkFailureReason(error: unknown, abortSignal: AbortSignal | undefined, timeoutMs?: number): string;