SpaceXAI released Grok 4.5, its strongest model to date and the first shipped since the company went public and folded in the AI coding startup Cursor. Elon Musk described it as an "Opus-class" model, meaning it targets the capability tier occupied by Anthropic's Opus 4.8, but the pitch is explicitly about efficiency rather than raw ceiling: Grok 4.5 is positioned as faster, markedly more token-efficient, and much cheaper. It is priced at two dollars per million input tokens and six dollars per million output tokens, against Opus 4.8's five and twenty-five, so it undercuts the reference Opus tier by roughly a factor of three on input and more than four on output.
The model was trained alongside Cursor, and the framing is a coding-and-agentic tool more than a consumer chatbot. The headline efficiency claim is on token economy: on SWE-Bench Pro tasks, SpaceXAI reports Grok 4.5 needs on the order of fifteen thousand nine hundred output tokens on average to complete a task, roughly four-point-two times fewer than Opus 4.8. Because agentic coding cost is dominated by output tokens spun across many tool-calling turns, a four-fold reduction in tokens-per-task compounds with the lower per-token price, so the effective cost delta on a real coding workload is larger than the sticker price alone suggests.
Availability is immediate but staged. Grok 4.5 is live in Grok Build, inside Cursor across all plans, and through the SpaceXAI console, but it is not yet offered in the European Union. The timing is conspicuous: it landed the day before OpenAI's GPT-5.6 family reached general availability, and the Latent Space AINews roundup framed it as the last moment anyone would be excited about a GPT-5.5-equivalent release before the next OpenAI generation arrived.
The interesting structural signal is what the Cursor acquisition buys: a captive stream of real engineering interaction data and a distribution channel where the model is the default coding backend, rather than one option among many behind an API. Grok 4.5 is the first concrete output of that combination, and its aggressive token efficiency on SWE-Bench Pro is the number to watch, because it is exactly the axis where coding-agent deployments live or die on cost. The caveat is that SWE-Bench Pro itself is under scrutiny for reliability, and independent replication of the token-efficiency figures outside SpaceXAI's own harness has not yet landed.
- Axios ran the scoop, framing it as SpaceXAI's first model since going public and acquiring Cursor.
- TechCrunch emphasized the pricing gap: two dollars / six dollars versus Opus 4.8's five / twenty-five.
- MarkTechPost led with the token economy — about fifteen thousand nine hundred output tokens on SWE-Bench Pro, roughly 4.2x fewer than Opus 4.8.
- Latent Space framed the timing as deliberate, landing one day before GPT-5.6's general availability.