# CookieTransport HTTP transport that reads credentials from a Bitcoin Core `.cookie` file on each call, enabling lazy authentication without hardcoded credentials. ``` struct CookieTransport ``` ## Overview The cookie file is written by Bitcoin Core at startup and deleted on shutdown. Its format is `__cookie__:`. Credentials change on every daemon restart, so this transport reads them fresh per-request. Conforms to [`WalletCapableTransport`](/documentation/Bitcoin/WalletCapableTransport) because it delegates to [`HTTPTransport`](/documentation/Bitcoin/HTTPTransport), which supports wallet path scoping.