Build advanced reasoning agents with GPT-5.1, a specialized AI model optimized for complex logic and chain-of-thought tasks. This model delivers cost-effective pricing at $1.25/1M input and $10.00/1M output tokens, native tool calling support. Access GPT-5.1 via the ZenMux API with up to 64K output tokens.
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GPT-5.1 by ZenMux costs $1.25 per 1M input tokens and $10.00 per 1M output tokens. Cached reads cost $0.12 per 1M tokens.