OpenAI: GPT-5.6 Terra

OpenAI's GPT-5.6 Terra accepts text, image, and file inputs and offers a context window of 1,050,000 tokens, with up to 128,000 tokens of output per response. It supports tool calling and reasoning, so it can handle multi-step tasks that draw on very large inputs. Structured output support is not listed, so teams that depend on strict schema adherence should verify it before committing. Pricing is $2 per million input tokens and $12 per million output tokens; output costs six times as much as input, so long generations will drive the bill more than large prompts. The model posts a blended benchmark score of 71.1, but that figure rests on a single independent benchmark, with an AI Index score of 69.4, so its standing is thinly evidenced. Shortlist it if you need very long context with file and image input alongside tools, and run your own evaluations before treating the score as decisive.