/**
 * Provider-level retry utility for AI SDK calls (NL11)
 *
 * The Vercel AI SDK's `generateText()` and `streamText()` have built-in retry
 * logic (`_retryWithExponentialBackoff()` with default `maxRetries: 2`) that
 * retries on HTTP 429/500/503. These retries are completely invisible to OTel
 * because they happen inside the AI SDK.
 *
 * This module provides an instrumented retry wrapper that:
 * 1. Disables the AI SDK's internal retries (via `maxRetries: 0`)
 * 2. Implements our own retry loop with full OTel span events
 * 3. Records retry attempts, delays, status codes, and total attempt count
 *
 * @module utils/providerRetry
 */
import { type Span } from "@opentelemetry/api";
/** Maximum number of retry attempts after the initial call (total = 1 + MAX_PROVIDER_RETRIES). */
export declare const MAX_PROVIDER_RETRIES = 2;
/** Base delay in ms for exponential backoff between retries. */
export declare const BASE_RETRY_DELAY_MS = 1000;
/** Minimum delay in ms when a retryable response provides no retry timing. */
export declare const NO_HINT_FLOOR_MS = 10000;
/**
 * Maximum server-requested retry delay honored by provider retries.
 *
 * A hint above this cap is not clamped-and-slept: the server declared an
 * unavailability window we are not willing to wait out, so the error is
 * surfaced immediately instead — fallback orchestration (providerFallback /
 * modelChain) can route to another provider, and callers without fallback
 * get a prompt rate-limit error rather than a silent multi-minute stall.
 */
export declare const MAX_RETRY_AFTER_MS = 60000;
/**
 * Check whether an error thrown by the AI SDK is retryable.
 *
 * Uses `APICallError.isInstance()` for proper type-safe detection (the class
 * uses a branded symbol marker, so `instanceof` doesn't work across package
 * boundaries). Falls back to duck-typing for non-APICallError cases.
 */
/**
 * Duck-typed HTTP status extraction for errors of unknown provenance.
 * NeuroLink's hand-rolled clients stamp `.statusCode`; official SDK errors
 * (e.g. @anthropic-ai/sdk APIError) expose `.status`. Shared with
 * baseProvider's handleProviderError metadata preservation.
 */
export declare function duckTypedStatusCode(error: unknown): number | undefined;
/**
 * Duck-typed Retry-After extraction for errors of unknown provenance.
 * Reads a pre-parsed `.retryAfterMs` (stamped by metadata-preserving
 * wrappers like handleProviderError), then `.headers` (Headers instance or
 * record — e.g. @anthropic-ai/sdk APIError), then `.responseHeaders` (the
 * hand-rolled OpenAI-compatible client's record). Shared with baseProvider.
 */
export declare function extractRetryAfterMsFromError(error: unknown): number | undefined;
/**
 * OpenAI's chat transport keeps the type inside the JSON response body,
 * rather than stamping it onto the raw error.
 */
export declare function readOpenAIBodyErrorType(responseBody: unknown): string | undefined;
/**
 * An OpenAI-wire `insufficient_quota` error: the account is out of credit or
 * has hit a spend cap.
 *
 * Exported and shared with the OpenAI error table so the retry predicate and
 * the message a caller sees cannot disagree about what a permanent billing
 * state looks like. The type is NOT a field on the error — OpenAI puts it
 * inside the JSON response body, which the SDK keeps as a string — so any
 * caller that needs it has to parse, and none should do so on its own.
 *
 * Deliberately keyed on the error TYPE, never on the word "quota". OpenAI and
 * xAI send 429 + `type: "insufficient_quota"` for a permanent billing state,
 * but other providers use "quota" for ordinary throttling — Google's 429 reads
 * "Quota exceeded for quota metric ...", which IS retryable and must stay that
 * way. Matching free text here would make Gemini throttling non-retryable and
 * quietly remove a layer of resilience.
 */
export declare function isOpenAIQuotaExhaustedError(error: unknown): boolean;
export declare function isRetryableProviderError(error: unknown): boolean;
/**
 * Extract the HTTP status code from an AI SDK error, if available.
 */
export declare function getErrorStatusCode(error: unknown): number | undefined;
/**
 * Execute a provider call with instrumented retry logic.
 *
 * @param operation  - The async operation to execute (should already use `maxRetries: 0`)
 * @param span       - The OTel span to annotate with retry events and attributes
 * @param label      - A human-readable label for log messages (e.g. "generateText", "streamText")
 * @returns The result of the operation
 */
export declare function withProviderRetry<T>(operation: () => Promise<T>, span: Span | undefined, label: string, sleep?: (delayMs: number) => Promise<void>): Promise<T>;