/**
 * CAIP-2 chain identifier helpers, EVM-scoped (`eip155:<chainId>`).
 *
 * CAIP-2 is the canonical chain id format on disk and across registry
 * APIs. Friendly slugs (`"ethereum"`, `"optimism"`) live alongside
 * CAIP-2 in chain entries for human-facing flags; CAIP-2 is the source
 * of truth.
 */
export type CaipChainId = `${string}:${string}`;
export type Eip155CaipChainId = `eip155:${string}`;
export declare class InvalidCaip2Error extends Error {
    constructor(input: string, reason: string);
}
export declare class NonEvmCaip2Error extends Error {
    constructor(input: string);
}
export type ParsedCaip2 = {
    namespace: string;
    reference: string;
};
export declare function parseCaip2(input: string): ParsedCaip2;
export declare function formatEvmCaip2(chainId: number): Eip155CaipChainId;
export declare function caip2ToEvmChainId(caip2: string): number;