import { type Span } from '@opentelemetry/api';
/**
 * A function with the same shape as `fetch`.
 *
 * Kept local instead of importing from `@cleverbrush/client` so this
 * entrypoint remains structurally compatible without a runtime dependency.
 */
export type FetchLike = (url: string, init: RequestInit) => Promise<Response>;
/**
 * Middleware shape accepted by `@cleverbrush/client`.
 */
export type ClientMiddleware = (next: FetchLike) => FetchLike;
/**
 * Endpoint metadata attached to `RequestInit` by `@cleverbrush/client`.
 *
 * This is intentionally structural and partial so the OTel package can read
 * metadata when present without coupling to client internals at runtime.
 */
export interface ClientTracingEndpointMeta {
    group?: string;
    endpoint?: string;
    method?: string;
    path?: string;
    collectionPath?: string;
    operationId?: string | null;
    tags?: readonly string[];
}
/**
 * Information passed to the `enrichSpan` hook.
 */
export interface ClientTracingInfo {
    url: string;
    method: string;
    headers: Record<string, string>;
    endpoint?: ClientTracingEndpointMeta;
}
/**
 * Configuration for {@link clientTracingMiddleware}.
 */
export interface ClientTracingMiddlewareOptions {
    /**
     * Tracer name used when resolving the OTel tracer.
     *
     * @default '@cleverbrush/otel'
     */
    tracerName?: string;
    /** Tracer version. */
    tracerVersion?: string;
    /**
     * Predicate for skipping tracing on selected outbound requests.
     */
    skip?: (url: string, init: RequestInit) => boolean;
    /**
     * Hook for adding custom attributes/events before the request is sent.
     * Errors thrown here are swallowed.
     */
    enrichSpan?: (span: Span, info: ClientTracingInfo) => void;
    /**
     * Whether to record `url.full`.
     *
     * Disabled by default because full URLs can include query strings with
     * sensitive values.
     *
     * @default false
     */
    recordUrlFull?: boolean;
}
/**
 * Creates a `@cleverbrush/client` middleware that traces outbound HTTP calls
 * and injects W3C Trace Context headers.
 *
 * Register this as the first client middleware so it wraps retries, timeouts,
 * and batching. The server-side `tracingMiddleware` already extracts these
 * headers, so downstream services join the same distributed trace.
 *
 * @example
 * ```ts
 * import { createClient } from '@cleverbrush/client';
 * import { clientTracingMiddleware } from '@cleverbrush/otel/client';
 *
 * const client = createClient(api, {
 *     baseUrl: 'http://service-b:3000',
 *     middlewares: [clientTracingMiddleware()]
 * });
 * ```
 */
export declare function clientTracingMiddleware(options?: ClientTracingMiddlewareOptions): ClientMiddleware;