gpt-5.1-chat-latest

GPT-5.1 is the latest flagship model, part of the GPT-5 family, and comes in both Instant and Thinking versions, significantly enhancing its capabilities in code generation, reasoning, and system integration. Its 256K context window improves project understanding, leading in SWE-bench test performance and supporting multi-step agent tasks. The Instant version is the most widely used model, capable for the first time of adaptive reasoning—allowing it to decide whether to "think before answering" when tackling more challenging questions, resulting in a more human-like, conversational, and empathetic interaction. It’s also warmer, smarter, and better at comprehending and executing user instructions.

As the most advanced model to date, GPT-5.1 employs training methods similar to those of its predecessors:

• code generation, error correction, and refactoring
• following instructions
• long-context processing and tool invocation

Compared to GPT-5:

1. GPT-5.1 features a default setting that feels friendlier and more natural, with enhanced conversational abilities.
2. Its ability to follow instructions has been further refined.
3. For the first time, it leverages adaptive reasoning technology, enabling the model to autonomously determine when to engage in deeper thinking before responding to particularly complex queries, ensuring faster responses while delivering more comprehensive and accurate answers.