Best AI model for agents
Agents multiply every weakness: a model that drifts after forty tool calls or costs ten times more per step is not an agent model, whatever the benchmark says.
- 1
Claude Opus 5.5 · Anthropic
The model people actually ship agents on: top of the independent index, a price that does not need a budget meeting, and a community that complains mainly about how much it has to be used.
Caveat: Arena puts Gemini 4 Argon ahead on chat preference; the gap is inside two scores' error bars.
- 2
Claude Sonnet 5.5 · Anthropic
The value pick of the table: second on the index at a fifth of the Opus price, and the fastest of the top five.
- 3
GPT-6.1 Sol · OpenAI
Near-Astra intelligence at a fifth of the price, which is OpenAI's own line and, for once, the index agrees.
- 4
Claude Fable 5.1 · Anthropic
The specialist: Anthropic's own docs say to reach for it when Opus 5.5 at high effort still falls short, and the price says the same.
Caveat: Ten dollars per million input is the highest in this table alongside Astra.
Head to head
Questions people ask
What is the best AI model for agents right now?
Claude Opus 5.5 (Anthropic) leads this list as of October 2026: The model people actually ship agents on: top of the independent index, a price that does not need a budget meeting, and a community that complains mainly about how much it has to be used. It costs $4 per million input tokens and $20 per million output tokens on the vendor's list price.
What is the runner-up for agents?
Claude Sonnet 5.5 (Anthropic): The value pick of the table: second on the index at a fifth of the Opus price, and the fastest of the top five.
How is this list ranked?
By the Models at Work leaderboard score: Score is 0 to 100: 50% independent evals normalised within this table, 20% price-performance, 15% practitioner sentiment from Signals and community threads, 15% operational fit (context, speed, availability, open weights). Models within three points are a tie in practice. Vendor-published figures are labelled as such and never counted as independent.
Other jobs
Every figure links to its source on the model profile pages. Vendor figures are labelled as vendor figures and never counted as independent.