Agent Arena Leaderboard: Claude Opus 5.5 Tops GPT 6 Astra Across 2.3M Agent Sessions
arena · x · 2026-10-09
Agent Arena has published a dynamic leaderboard ranking 52 models on real-world agentic tasks, built from about 2.38 million sessions and signals like tool reliability, task completion, and steerability.
Key standings:
- Claude Opus 5.5 (High) from Anthropic holds #1, up 6 places, with 14.33% confirmed success and the top Bash recovery score among leaders (13.55%).
- OpenAI's GPT 6 Astra (Max) is #2 at 13.09%, with the highest praise-vs-complaint ratio (38.54%).
- Claude Fable 5.1 (Max) ranks #3 but is the most expensive at $6.31 median cost per task; GPT 6 Sol (Max) is the cheapest in the top group at $0.58.
- Google's Gemini 4 Argon (High) sits #7 with the best Bash recovery rate in the top 10 (21.41%) and a 0.18% tool hallucination rate.
The board also tracks output tokens per task and list pricing, where leaders range from $2/$10 to $10/$50 per million tokens.
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