Elon Musk says ‘unsustainably high’ costs are the reason for Grok Bot usage limits

• Elon Musk said that the cost of providing SpaceX’s Grok Bot was “unsustainably high.”
• Musk was responding to users complaining that they’d maxed out their usage limits for the AI agent.
• Agents like Grok Bot and Muse are Silicon Valley’s next big thing, but they’re still burning through cash.

Elon Musk says an age of AI abundance is coming. For now, that doesn’t include unlimited Grok Bot.

The SpaceX CEO wrote on X on Sunday that the cost of serving the company’s AI agent was “unsustainably high relative to revenue,” after some users complained that their weekly allowances were running out faster than usual.

SpaceX launched Grok Bot, an AI agent that uses a virtual computer to perform tasks on behalf of humans, like shopping, in August. It’s available in a series of tiers ranging from free to $200 a month.

All of those tiers come with varying usage limits that refresh weekly, a tactic employed by SpaceX and other AI agents, such as Meta’s Muse, to prevent users from racking up massive AI bills.

Numerous Grok Bot users posted on X over the weekend, saying they had maxed out their usage sooner than expected, prompting Musk to weigh in.

“Upgrade to higher usage plan cost increase is too high?” the billionaire wrote in response to one user, adding in another X reply that reducing allowances and communicating it to users was “just being sensible.”

SpaceX said that Grok Bot had 800,000 paid weekly users in its earnings last month, with Musk telling investors the AI agent had “the fastest growth of a product that I’ve ever seen in my life.”

“I think Grok Bot may end up being what uses most of our Super Intelligence compute,” he added.

SpaceX recently announced it would roll Grok Bot into a new $8-a-month “X subscription” that also includes X premium and Cursor, the AI coding platform it acquired earlier this year. In October, Musk said that the AI agent would also use AI models other than Grok, including Claude Opus 5.5, MidJourney, and Suno.

AI agents have become the tech industry’s hottest new trend, but there are still questions about how they will make money.

Meta has not said how much Muse, which has been a major hit for the company and now has over 10 million users, costs to run, but CEO Mark Zuckerberg told investors last month that the agent is “very compute-intensive” and is not yet profitable.

Musk’s admission that Grok Bot is burning a hole in SpaceX’s wallet sparked mockery from some X users, who pointed out his recent comments suggesting saving money is “pointless” due to a fast-approaching age of AI abundance.