import { type PackedSkillBundle } from "./skill-bundle.js";
/** Environment variable holding the HMAC signing key. Never logged, never printed. */
export declare const SKILLS_SIGNING_KEY_ENV = "SKILLS_SIGNING_KEY";
/** Environment variable naming the source commit the bundle was built from. */
export declare const SKILLS_SOURCE_COMMIT_ENV = "SKILLS_SOURCE_COMMIT";
/** Prefix of the signature string. The remainder is lowercase hex. */
export declare const SIGNATURE_PREFIX = "hmac-sha256:";
export interface SkillBundleManifest {
    name: string;
    version: string;
    source_commit: string;
    /** Canonical sha256 of the bundle bytes (the skill's content address). */
    content_hash: string;
    /** `hmac-sha256:<hex>` over the bundle bytes. Omitted when no key is available. */
    signature?: string;
    published_at: string;
}
export interface BuildSkillBundleOptions {
    name: string;
    /** The skill directory to pack. */
    dir: string;
    version: string;
    /** Source commit the skill came from. `unknown` when the provenance is unavailable. */
    sourceCommit: string;
    /** Signing key. Defaults to reading process.env[SKILLS_SIGNING_KEY_ENV]. */
    signingKey?: string;
    /** Explicit published_at. Defaults to now. Tests only. */
    publishedAt?: string;
}
export interface BuiltSkillBundle {
    bundle: PackedSkillBundle;
    manifest: SkillBundleManifest;
}
/**
 * Resolve the signing key from the environment. Returns null when unset, and the
 * caller decides how to behave (omit the signature, warn, or refuse) — this function
 * never touches stdout, so nothing about the key can leak through it.
 */
export declare function resolveSigningKey(env?: Record<string, string | undefined>): string | null;
/** Sign canonical bundle bytes with an HMAC key. Returns `hmac-sha256:<hex>`. */
export declare function signBundleBytes(bytes: Uint8Array, key: string): string;
/**
 * Verify a signature string against bundle bytes and a key. Returns true only for a
 * well-formed `hmac-sha256:<hex>` signature computed over exactly these bytes.
 * timingSafeEqual keeps the comparison from leaking a byte-at-a-time signal; the
 * length check is a format check (a hex digest is a fixed length), not a leak.
 */
export declare function verifyBundleSignature(bytes: Uint8Array, signature: string, key: string): boolean;
/**
 * Pack a skill directory and build its signed manifest in one call — the unit the CI
 * bundle script, push, and pull all share, so a bundle built by CI and one pushed by
 * a machine agree on the canonical content_hash by construction.
 */
export declare function buildSkillBundle(options: BuildSkillBundleOptions): BuiltSkillBundle;