Rather than producing unrestricted text, it evaluates a supplied state against typed questions and returns probabilities for permitted answers.
The state can be text, JSON, images, or video. The API supports 1 to 64 questions per request, using noul, choice, or score question types. It also exposes a clef-flash selector. Clef has a 65,536-token context window and accepts up to four embedded PNG, JPEG, or WebP images; remote image URLs are not accepted.
Cloudflare lists input pricing at $0.24 per million tokens and says there is no output-token charge. Images are converted to input tokens, capped at 1,024 tokens each. The documentation does not establish a release date, availability by plan or region, benchmark results, or how Clef compares with other decision models.