Grok Bot now runs on Anthropic’s Claude, with Midjourney and Suno next

Grok Bot, the AI agent app from Elon Musk’s SpaceXAI, will no longer lean only on in-house Grok models. In a post on X on 7 October, Musk said SpaceX “will use the best back end model for any given task, including Claude Opus 5.5, MidJourney, Suno and other leading APIs”, adding: “Whatever is most likely to give you the best outcome.”

The models he named cover text and reasoning (Anthropic’s Claude), images (Midjourney) and music (Suno). Musk’s post gave no timeline and didn’t say which jobs go to which provider.

Claude becomes the default brain

Later the same day, a member of the Grok Bot team filled in part of the picture. Lauren (@poteto), who works on Grok Bot at SpaceXAI, wrote on X that “all bots will be powered by opus 5.5”, and that they can spawn cloud agents running any of the Cursor models the company has. Per 9to5Mac, Grok Bot can use Claude Opus 5.5 as of 7 October.

That makes Claude the main model behind every Bot rather than an occasional pick for specific tasks. It’s an unusual step for a company that launched Grok 4.7 only in September, a model SpaceXAI said was trained to understand the Grok Bot harness. Anthropic released Claude Opus 5.5 in late September at lower prices than its predecessor.

Midjourney and Suno look like gap-fillers. Grok already has its own image generator, Imagine, but SpaceXAI has no music model, so Suno adds something Grok Bot couldn’t do in-house.

What Grok Bot does

Grok Bot launched in beta in August. Each Bot works on its own cloud computer and can run several tasks in parallel. The apps run on iPhone, iPad and Mac, and the service isn’t sold on its own: it comes bundled with most SuperGrok and paid Cursor plans.

The official changelog shows how fast features are landing. Recent releases let Bots build slide decks and deliver them as PowerPoint files or Google Slides, send formatted emails, and search a Gmail spam folder. The Bot’s computer screen also went up to 1920 × 1200 from 1280 × 800. Since late September, teams can publish a shared Bot that colleagues use in the app or in Slack.

Rivals on both sides

The relationship with Anthropic already ran the other way. Anthropic rents compute from SpaceX at its Colossus 1 data centre, which holds more than 220,000 Nvidia GPUs, to power Claude. Routing Grok Bot through Claude makes SpaceXAI a customer as well as a supplier.

Corporate lines have blurred too. SpaceX acquired xAI effective 2 February 2026, according to its June prospectus as reported by Runtime Wire, and it bought Cursor in August in a $60 billion deal. This week, Musk also said SpaceXAI will take the name SpaceXSI, The Next Web reported.

The agent market Grok Bot competes in is getting crowded. Meta’s Muse reportedly passed 3 million weekly users, while OpenAI is building out ChatGPT Dot. Per Bloomberg, Grok Bot reached 418,000 weekly users in the week ending 14 September. The announcement also came a day after users reported trouble reaching Grok’s mobile and web services, City AM reported. SpaceXAI gave no official cause.

What’s still unclear

So far, the change rests on posts by Musk and a staff member, not a product page. SpaceXAI hasn’t said when Midjourney and Suno will be used, whether users can see or choose which model handled a task, or whether outside models will use up plan limits faster. Claude Opus 5.5 is among the pricier models available, so the last point matters for heavy users.

Data handling is another open question. A task sent to Claude, Midjourney or Suno means data goes to those companies, and SpaceXAI hasn’t published terms on what’s shared.