https://redis.io/docs/latest/commands/xreadgroup describes the CLAIM arg, which is not available up until Redis 8.4. This fact is never once actually mentioned on the page.
Furthermore, https://redis.io/docs/latest/commands/redis-6-2-commands/#stream-commands (and similar pages for consecutive versions) describes the CLAIM arg in the XREADGROUP sections, which is false and just wasted me a couple hours of debugging a generic syntax error. Please add a mention of the version, in which CLAIM was actually added.