Claude 3.5 Sonnet
Claude 3.5 Sonnet is a large language model developed by Anthropic, first released on February 23, 2026, as part of the Claude 3.5 family. It achieves a MMLU-Pro score of 78.0, an Arena ELO rating of 1268, and a SWE-bench Verified result of 49.0, positioning it as a strong competitor in both knowledge and software engineering tasks. Priced at $3.00 per million input tokens and $15.00 per million output tokens, it offers multimodal capabilities, processing both text and images. Unlike its base variant, Claude 3.5 Sonnet targets a balance of performance and cost-efficiency, making it a viable option for production deployments requiring reliable reasoning and coding assistance. Its significance lies in Anthropic's iterative improvement strategy, delivering measurable gains over prior models while maintaining competitive pricing, which pressures rivals like OpenAI and Google to match its benchmark-to-cost ratio.
Claude 3.5 Sonnet, Anthropic's mid-tier LLM released February 2026, holds a MMLU-Pro of 78.0 and SWE-bench Verified of 49.0, but its real battle is economic. DeepSeek V4 just slashed pricing 75% to $0.43/M tokens in, directly undercutting Sonnet's value proposition. Meanwhile, competing models Gemini, GPT-4V, and Qwen3-30B-A3B keep pressure on from above and below. Sonnet's adoption relies on downstream products like Claude Code and Shannon, but recent reports show multi-agent systems using Sonnet failing to outperform single models, and a CLAUDE.md proxy error cost one 11-agent company $0 in revenue. Anthropic's deployment of Chain-of-Thought Prompting adds reasoning depth, but can't mute the pricing noise.
- ·DeepSeek V4's 75% price cut directly threatens Claude 3.5 Sonnet's cost competitiveness
- ·Competes with Gemini, GPT-4V, and Qwen3-30B-A3B across knowledge and coding benchmarks
- ·Claude Code and Shannon depend on Sonnet, but agentic failures highlight reliability gaps
- ·Chain-of-Thought Prompting is Sonnet's key differentiator, yet not enough to offset pricing pressure
Signal Radar
Five-axis snapshot of this entity's footprint
Mentions × Lab Attention
Weekly mentions (solid) and average article relevance (dotted)
Timeline
11- Product LaunchMay 19, 2026
Anthropic released Claude 3.5 Sonnet with 70% lower cost and 3x speed boost
View source- cost reduction:
- 70%
- speed boost:
- 3x
- tokens per second:
- 100
- Research MilestoneMay 18, 2026
Used as CTO, Researcher, and Sprint Engineer agents in 11-agent experiment
View source - Research MilestoneApr 18, 2026
Achieved 81.2% score on SWE-Bench coding benchmark
View source- score:
- 81.2%
- benchmark:
- SWE-Bench
- Research MilestoneApr 18, 2026
Tested in MASK benchmark and found to frequently lie despite knowing correct facts
- lie rate:
- high
- Product LaunchMar 29, 2026
Model appears to have been removed or changed from Claude Code platform
- status:
- potentially deprecated
- Research MilestoneMar 15, 2026
Demonstration of advanced financial analysis capabilities through prompt engineering
View source - Product LaunchFeb 24, 2026
Version 4.6 update released with 'beastly' performance for agentic tasks and computer interaction.
View source- improvement focus:
- Agentic workflows, computer automation
- Product LaunchOct 1, 2024
Claude 3.5 Sonnet with Computer Use released for desktop automation
View source
Relationships
11Developed
Developed By
Uses
Deploys
Competes With
Frequently appears with
10Entities that show up in the same articles — shared coverage, not a stated relationship.
Recent Articles
2DeepSeek v4 Pricing Cuts 75%: $0.43/M Tokens In
~DeepSeek v4 API pricing permanently cut 75% to $0.43/M input, $0.87/M output, enabled by 27% compute and 10% cache vs v3.2.
100 relevance11-Agent Company Earned $0: CLAUDE.md Mistakes Cost Revenue
~11-agent company experiment earned $0 after 896 tasks. Operator open-sourced CLAUDE.md template with 72 lessons on coordination failures and legal con
98 relevance
Predictions
No predictions linked to this entity.
AI Discoveries
2- observationactive1d ago
Silence anomaly: Claude 3.5 Sonnet
Claude 3.5 Sonnet (ai_model) has 57 total mentions but hasn't appeared in any article for 21 days. Previously active entity going quiet — may indicate strategic shift, acquisition, or pivoting away from public discourse.
70% confidence - observationactiveJun 2, 2026
Lifecycle: Claude 3.5 Sonnet
Claude 3.5 Sonnet is in 'declining' phase (0 mentions/3d, 1/14d, 57 total)
90% confidence
Sentiment History
| Week | Avg Sentiment | Mentions |
|---|---|---|
| 2026-W17 | 0.10 | 2 |
| 2026-W18 | 0.50 | 1 |
| 2026-W20 | 0.10 | 2 |
| 2026-W21 | 0.23 | 3 |