import { type Cache1hMode, type ClaudeCodeIdentity } from '@cortexkit/anthropic-auth-core';
export type FetchInput = string | URL | Request;
/**
 * Merge headers from a Request object and/or a RequestInit headers value
 * into a single Headers instance.
 */
export declare function mergeHeaders(input: FetchInput, init?: RequestInit): Headers;
/**
 * Merge incoming beta headers with the required OAuth betas, deduplicating.
 */
export declare function mergeBetaHeaders(headers: Headers): string;
export declare function addFastModeBetaHeader(headers: Headers): Headers;
/**
 * Set OAuth-required headers on the request: authorization, beta, user-agent.
 * Removes x-api-key since we're using OAuth.
 */
export declare function setOAuthHeaders(headers: Headers, accessToken: string, options?: {
    body?: Record<string, unknown> | null;
    identity?: ClaudeCodeIdentity;
}): Headers;
/**
 * Add TOOL_PREFIX to tool names in the request body.
 * Prefixes both tool definitions and tool_use blocks in messages.
 */
export declare function prefixToolNames(parsed: Record<string, unknown>): string;
/**
 * Strip TOOL_PREFIX from tool names in streaming response text.
 */
export declare function stripToolPrefix(text: string): string;
/**
 * Check if TLS verification should be skipped for custom API endpoints.
 * Only effective when ANTHROPIC_BASE_URL is also set.
 */
export declare function isInsecure(): boolean;
/**
 * Rewrite the request URL to add ?beta=true for /v1/messages requests.
 * When ANTHROPIC_BASE_URL is set, overrides the origin (protocol + host)
 * for all API requests flowing through the fetch wrapper.
 * Returns the modified input and URL (if applicable).
 */
export declare function rewriteUrl(input: FetchInput, options?: {
    baseURL?: string;
}): {
    input: FetchInput;
    url: URL | null;
};
/**
 * Sanitize a system-prompt block. Memoised: the prompt is stable within a
 * session, so the paragraph-filter + regex pass is skipped on cache hits.
 */
export declare function sanitizeSystemText(text: string): string;
export declare function getSanitizeMemoStats(): import("./sanitize-memo").SanitizeMemoStats;
type SystemBlock = {
    type: string;
    text: string;
    [k: string]: unknown;
};
/**
 * Sanitize system prompt and prepend Claude Code identity.
 * Handles all Anthropic API system formats: undefined, string, or array of text blocks.
 */
export declare function prependClaudeCodeIdentity(system: unknown): SystemBlock[];
export type HybridMessageCacheAnchor = {
    fingerprint: string;
    messageIndex: number;
    messageCount: number;
};
export declare function extractLatestHybridMessageCacheAnchor(bodyText: string): HybridMessageCacheAnchor | undefined;
export declare function prepareFableCacheWarmSource(bodyText: string, fableModel?: string): {
    ok: true;
    bodyText: string;
} | {
    ok: false;
    reason: string;
};
/**
 * Rewrite the full request body: sanitize system prompt and prefix tool names.
 */
type RewritePerfCallback = (stage: string, data?: Record<string, unknown>) => void;
export declare function rewriteRequestBody(body: string, options?: {
    cache1hEnabled?: boolean;
    cache1hMode?: Cache1hMode;
    fastModeEnabled?: boolean;
    identity?: ClaudeCodeIdentity;
    perf?: RewritePerfCallback;
    hybridStandbyAnchor?: HybridMessageCacheAnchor;
}): Promise<string>;
/**
 * Create a streaming response that strips the tool prefix from tool names.
 */
export declare function createStrippedStream(response: Response, options?: {
    perf?: RewritePerfCallback;
    onContentFilter?: () => boolean | undefined;
    onComplete?: (finishReason: string) => void;
    contentFilterModel?: unknown;
}): Response;
export {};