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View on OpenRouter Measuring Autonomous AI Research
We ran 153 autonomous runs across 18 frontier models on the nanoGPT optimizer speedrun.
Elie Bakouch
Claude Sonnet 5
Claude Sonnet 5 is built to be the most agentic Sonnet model yet. It can make plans, use tools like browsers and terminals, and run autonomously at a level that, just a few months ago, required larger and more expensive models.
Specs
Model
- Family
- Claude
- Variant
- Sonnet 5
- Weights
- Proprietary
Limits
- Context
- 1,000,000 tokens
- Max output
- 128,000 tokens
Modalities
- Input
- Text Image PDF
- Output
- Text
Pricing
- Input
- $2 / 1M
- Output
- $10 / 1M
- Cache read
- $0.2 / 1M
- Cache write
- $2.5 / 1M
Capabilities
- Reasoning
- Yes
- Reasoning control
- On / off, Effort levels
- Tool calling
- Yes
- Attachments
- Yes
Dates
- Released
- 29 Jun 2026
- Updated
- 30 Jun 2026
- Knowledge cutoff
- 31 Jan 2026
Articles
All articlesprimeintellect.ai
Introducing DataBench
DataBench v1: 100 realistic analytical tasks across Q&A and open-ended prompts, run in a synthetic Hex workspace — built because existing analytics benchmarks test "overspecified pub trivia" rather than the vague, directional questions people actually ask.
Hex@_hex_tech
Introducing Claude Sonnet 5
Our most agentic Sonnet yet, with top-tier intelligence for coding and everyday professional work.
anthropic.com
The advisor strategy: Give Sonnet an intelligence boost with Opus
Pair Opus as an advisor with Sonnet or Haiku as an executor, and get Opus-level intelligence in your agents at a fraction of the cost.
Anthropic
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