Cloudflare open-sources Clef decision models at 209.3 ms versus Jev's 524.1 ms

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Some LLM calls exist only to pick an option, like classifying a website. Cloudflare's Clef and Clef-flash are decision models built for that job. They classify inputs and return structured answers with probabilities your software can act on.

Here is what makes this credible:

• Across 43 benchmarks, Clef's median latency is 209.3 ms and Clef-flash's is 38.8 ms, versus Jev at 524.1 ms.
• On BFCL case exact, Clef scores 98.47 and Clef-flash 98.76, versus Jev at 95.75.
• Inference runs one prefill-only pass, then scores valid schema choices in parallel instead of generating text.
• Clef adds image input and a 64k context window, where Jev is text-only at 32k.
• The backbones are Qwen3.8-27B for Clef and Qwen3.5-9B for Clef-flash, and the API is Jev-compatible.

Fine-tuning starts as a hands-on service with Cloudflare engineers, with self-serve planned later.

One catch: Jev still leads on When2Call accuracy (80.97 versus 72.37) and BRIGHT nDCG@10.

Try it: POST to https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run/@cf/cloudflare/clef with a bearer token, or download the Apache 2.0 weights from Hugging Face.

Sources: blog.cloudflare.com