OpenAI: GPT-5.2 Pro

GPT-5.2 Pro is a text generation model from OpenAI, released by the provider on 10 December 2025. It sits in OpenAI's GPT-5 line as the Pro variant, positioned as the company's most advanced model, with the provider describing major improvements in agentic coding and long context performance over GPT-5 Pro. On api14 it is listed under the text category, so it is intended for language work rather than image, audio or video generation.

The model accepts text, images and files as input, and it returns text only. Its context window is 400,000 tokens, and the maximum output is 128,000 tokens, which means you can supply very large inputs (long documents, codebases, image sets alongside instructions) and still leave room for a substantial response. Because inputs can include images and files, the model can reason over more than plain chat text, but everything it produces comes back as text.

Those capabilities point to a fairly specific set of uses. The long context window and the provider's emphasis on step-by-step reasoning suit tasks such as analysing large documents or repositories, multi-step coding work, and agentic workflows where the model plans and calls tools across several turns. Image and file input make it usable for questions about screenshots, diagrams or attached documents, and the large output ceiling helps when you need a long structured answer rather than a short reply.

You call the model through api14's OpenAI-compatible API using the model id "openai/gpt-5.2-pro". The supported request parameters are include_reasoning, max_tokens, reasoning, reasoning_effort, response_format, seed, structured_outputs, tool_choice, tools and verbosity. In practice that means you can control the length of the response with max_tokens, tune how much reasoning effort the model applies, request structured or JSON-style output through response_format and structured_outputs, define and select tools for function calling, set a seed for reproducibility, and adjust verbosity or whether reasoning is included in the response.

There is no information here about pricing, rate limits or latency, so check the live price table and your own testing before committing to it. If your task is simple text generation, a smaller model may be cheaper and faster; GPT-5.2 Pro makes most sense when you actually need the long context, the reasoning depth or the tool use it supports.