GPT-6 Astra vs Claude Fable 5.1
A direct, empirical evaluation of GPT-6 Astra (OpenAI) against Claude Fable 5.1 (Anthropic).
GPT-6 Astra
Developed by OpenAI · Proprietary Frontier parameters
Complex multi-step engineering, formal math proofs, autonomous computer/browser navigation, and CAD synthesis.
Claude Fable 5.1
Developed by Anthropic · Proprietary Frontier parameters
Full-repository software refactoring, agentic tool workflows, formal verification, and 1.5M-token needle retrieval.