According to xAI's docs, under The X Subscription Grok Bot is included on the Premium ($30/mo), Super ($100/mo) and Ultra ($200/mo) plans. The Plus plan does not include it. Usage comes from a weekly pool shared across Grok, Grok Bot and Cursor. Super and Ultra give larger allowances (source).
Some existing customers get Grok Bot through a SuperGrok plan connected to Cursor. Switching to The X Subscription is optional, but once you combine accounts it is permanent. New customers start on The X Subscription.
Making the plan pay for itself
Routines use your allowance even while you sleep, so the cheapest setup runs a few high-value jobs at sensible intervals. A support sweep every 2 hours beats one every 5 minutes. Start with the recipes that save you the most hours per week.