From the source
Solar Pro 4 is built to carry real work to the finish, reading the documents, running the tools, producing the deliverable, and to stop and say so when the evidence runs out.
The work you hand to an AI rarely ends with a single question.
It's reviewing a contract, reconciling numbers across files, and verifying intermediate results before passing them to the next step.
One wrong value or one stalled step, and you're re-checking everything.
We built Solar Pro 4 against that bar.
Compared with Solar Pro 3, its agent capability took a major step up, and the gains are largest on evaluations that resemble real work: long documents, terminal tasks, multi-turn tool use.
And when the evidence isn't there, it says it can't verify instead of making something up.
To mark the launch, Solar Pro 4 is 90% off on Upstage Console and OpenRouter through September 10.
Solar Pro 4 supports a 512K context with up to 128K output tokens, the baseline for agent work that loads several contracts, reports, and data files into a single session without splitting them.
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