Grok 4.5 crushed Claude Fable 5 and Opus 4.8: Elon Musk proved superiority in an independent AI agent test
The AI agent market is undergoing a tectonic shift. SpaceXAI's Grok 4.5 model has not only confirmed Elon Musk's claims—it has crushed competitors in the AutomationBench-AA benchmark conducted by the independent analytical platform Artificial Analysis.
What did the AutomationBench-AA test show?
Grok 4.5 took first place with a result of 51.4% successful task completion. For comparison: Claude Fable 5 scored 48.6%, and Claude Opus 4.8 scored 48.5%. The gap of nearly 3 percentage points is not just numbers—it is a qualitative leap in agent performance.
The test included 657 tasks across 40 simulated applications, including Gmail, Slack, Salesforce, and HubSpot. The final score reflects the proportion of tasks completed without violating established rules—a strict criterion that excludes "dirty" victories.
Price and efficiency: Grok 4.5's main trump card
Perhaps the most impressive aspect is the cost. Grok 4.5 completes a task for $0.34, which is 4 times cheaper than Fable 5 ($1.35) and Opus 4.8 ($1.46). The closest competitor in price—Gemini 3.5 Flash at $0.49—still loses in performance.
The secret lies in the V9 architecture with 1.5 trillion parameters. Grok 4.5 uses only about 8,000 output tokens per task—just 25% of Opus 4.8's resources. This efficiency creates a massive price advantage that Musk bet on at launch.
Financial sector: where Grok 4.5 truly shined
In the test's most difficult category—finance—Grok 4.5 achieved 71% successful completions. Fable 5 scored 64%, Opus 4.8 scored 62%. For companies deploying agents in real financial systems, this is a critical gap.
However, there is a nuance: the model violates rules more often than competitors—averaging 0.63 violations per task compared to 0.55 for Opus 4.8 and 0.46 for Gemini 3.5 Flash. In finance, a single violation can lead to significant losses, so this is a weakness that SpaceXAI needs to address.
My expert opinion: Grok 4.5 is the undisputed leader in price/performance for mass AI agent adoption. But for high-risk financial operations, it is still better to look at more disciplined models like Opus 4.8. The agent market is entering a phase of maturity, and the race is just beginning.