OpenAI / current
The flagship GPT-5.6 model for complex professional work, advanced coding and tool-rich workflows.
A primary model for high-value work where accuracy, long-horizon execution and tool coordination matter more than unit cost. Official OpenAI guidance positions Sol as the default flagship for complex reasoning and coding. It accepts text and image input, can return up to 128K tokens, and exposes a broad tool surface through the Responses API.
Use the Responses API for multi-turn reasoning and tool workflows. Pin a snapshot when behavioral stability matters, preserve reasoning only where task state remains relevant, and benchmark xhigh against max before accepting the added latency and cost.
Complex work still needs evaluations, bounded tool permissions and fallbacks; flagship does not mean verification-free. Inputs above 272K tokens use long-context pricing. Treat reasoning effort, pro mode and tool permissions as evaluated product settings rather than universally maximizing them.
Specifications and positioning checked against provider documentation.
Open official source↗