OpenAI: GPT-5.2

The task this model is squarely built for is demanding, tool-using work over long inputs, where its adaptive reasoning allocates computation dynamically, moving quickly on simple prompts and thinking harder on difficult ones. As the latest frontier-grade release in the GPT-5 series, GPT-5.2 offers stronger agentic and long-context performance than GPT-5.1, so a fitting scenario is an agent that ingests a lengthy dossier, reasons across it, and calls external tools to assemble a structured answer without stalling on the easy parts. It provides a 400,000-token context window bigger than most models listed here, image input, chain-of-thought reasoning, tool and function calling, and structured JSON output. Against alternatives such as Claude Sonnet 5 or Gemini, its distinguishing pitch is that adaptive allocation of reasoning effort, aiming for frontier quality without spending peak compute on trivial requests, and unlike the far pricier 5.2 Pro it keeps cost moderate. Pricing is above average at 1.75 dollars per million input tokens, with no free tier. Ideal for teams running agentic research and writing workloads that mix easy and hard requests and want frontier capability at a mid-range price. Choose it as a capable, efficient frontier default; drop to a mini or nano variant for pure volume, or move up to Pro only when a task's difficulty truly warrants it.