Clef

Clef is a “decision model” that Cloudflare released on 1 October 2026, in a post by Michelle Chen. Rather than writing free text, it returns bounded, structured answers, a choice from a defined set with a probability for each, so that software agents can take routine decisions such as routing, moderation or approval cheaply, quickly and consistently. It accepts text or images with a 64,000-token context. Cloudflare says Clef is built on a frozen Qwen 3.8 27B backbone, and publishes the weights on Hugging Face under the Apache 2.0 licence; it also runs on Cloudflare’s Workers AI, for which the post gives no price. Cloudflare offers reinforcement-learning fine-tuning of Clef on a customer’s own data, at first as a service run with its own engineers, with a self-serve version to follow. Cloudflare says Clef currently leads the Jev Decision Index maintained by Typesafe AI; we have not read that index, so no score is stored. A smaller, faster variant, Clef-flash, was released at the same time.

Not yet independently verified: Every detail here comes from Cloudflare’s own announcement; no independent report was found. Cloudflare says Clef leads a third-party decision benchmark, which we have not read, and the post gives no Workers AI price. We will update this when it can be confirmed, and remove this note.