RADAR ARCHIVE
Week 4, 2025
2 tools added to the directory, Jan 20 – 26, 2025.
Added to the directory (2)
Tested and written up.
Chain-of-thought reasoning model for multi-step logical analysis
Sonar Reasoning Pro exposes explicit chain-of-thought reasoning to solve complex, multi-step problems with transparent intermediate steps. It is aimed at logical analysis, coding, and math tasks that require verifiable reasoning alongside live web search.
Why: Sonar Reasoning Pro is Perplexity's option for users who need transparent, step-by-step reasoning rather than just a final answer.
Paid
Best for Complex Reasoning
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The open-weight reasoning model that sparked the efficiency revolution
DeepSeek R1 is a 671B-parameter open-weight reasoning model that matches o1-class performance on math, code, and logic benchmarks through reinforcement learning on verifiable tasks. It exposes chain-of-thought reasoning and is available as MIT-licensed local weights and via API, with the R1-0528 update in May 2025 further improving math and code reasoning.
Why: R1 proved that open-weight models can match proprietary reasoning systems at a fraction of the cost, making it a landmark for reproducible AI research.
Freemium
Best for Open Reasoning
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