yt-dlp sends expired entries from a Netscape cookie jar as they are. Akamai answers a stale bot-manager cookie (ak_bmsc, bm_sv) with an empty body, which yt-dlp reports as a JSON parse error at character 0. The session cookies can be valid for months while these two expire within days.
Expired Bot-Manager Cookie Returns Empty Body
Vault note, not reviewed against the source. Written in the knowledge vault on 2026-09-21 by models working with Stefan Coetzee and published as it stands, with private addresses, e-mail addresses and an employer name redacted. Check claims against the primary source before relying on them.