/**
 * Byte and encoding helpers built exclusively on web-standard APIs.
 *
 * The SDK has to import and run unchanged on Node, in browsers, and in Edge
 * runtimes (Vercel Edge, Cloudflare Workers). Edge runtimes provide no Node
 * builtins and no `Buffer`, so nothing in the SDK's module graph may reach for
 * either — see the `check:edge` script, which fails the build if one creeps
 * back in.
 *
 * Everything here is available on Node >= 18 (the SDK's engine floor), in
 * every modern browser, and on both Edge runtimes: `globalThis.crypto`,
 * `btoa`/`atob`, and `TextEncoder`/`TextDecoder`.
 */
/**
 * Fill `length` bytes with cryptographically secure randomness.
 *
 * @throws If the host exposes no Web Crypto implementation.
 */
export declare function randomBytes(length: number): Uint8Array;
/** Hex-encode bytes. Replaces `Buffer.from(bytes).toString("hex")`. */
export declare function toHex(bytes: Uint8Array): string;
/** Base64-encode bytes. Replaces `Buffer.from(bytes).toString("base64")`. */
export declare function toBase64(bytes: Uint8Array): string;
/** Decode a base64 string to bytes. Replaces `Buffer.from(b64, "base64")`. */
export declare function fromBase64(base64: string): Uint8Array;
/**
 * Coerce the binary shapes callers pass as `contents` into a `Uint8Array`,
 * matching what `Buffer.from(value)` used to accept (minus the string
 * overload, which callers handle separately because it is not binary).
 *
 * @throws If `value` is not a recognized binary shape.
 */
export declare function toBytes(value: unknown): Uint8Array;
/**
 * View a typed array's bytes without copying, honoring its offset and length
 * (`.buffer` alone can be larger than the view).
 */
export declare function viewBytes(view: ArrayBufferView): Uint8Array;
/** UTF-8 decode bytes. Replaces `buffer.toString("utf8")`. */
export declare function decodeUtf8(bytes: Uint8Array): string;
/**
 * Hex-encoded SHA-256 of `data`, via Web Crypto.
 *
 * Async because `crypto.subtle.digest` is; Node's synchronous `createHash`
 * has no Edge equivalent.
 *
 * @throws If the host exposes no Web Crypto `subtle` implementation.
 */
export declare function sha256Hex(data: Uint8Array): Promise<string>;