Clef

Cloudflare's larger decision model for classifying information and choosing an action without generating a chat response.

Open provider docs See key facts

Plain-English overview

What Clef actually is

Clef uses a 27B backbone to evaluate information against questions you define. It returns choices, scores and probabilities that an application can use to route work or request human review.

Its System One-compatible interface makes it a relevant Jev alternative. Workers AI accepts text, JSON and up to four embedded images; the self-hosted model card also documents video-frame inputs. These are different deployment capabilities.

Good fit for

Support ticket classification and routing
Image-assisted document checks
Agent decisions with human escalation

Category comparison

The facts that matter for decision models

These are provider-published specifications, not Cody benchmark scores. Follow the linked sources for current limits and endpoint-specific exceptions.

Input price: $0.24 / 1M input tokensCurrent provider price for the text or structured state submitted to the model, including whether decision outputs are billed.
Input capacity: 65,536 tokens; up to 64 questions per requestMaximum documented state and question capacity for one request.
Decision types: Choice, Score, and Noul probability questionsThe bounded question forms the model can answer, such as choices, scores, or probabilities.
Output contract: Typed JSON decisions defined before inferenceHow the response is constrained for direct use by application code.
Uncertainty: Probability distributions; Choice and Score also include confidenceWhether the endpoint exposes probabilities, confidence, or another calibrated signal.
Where to use it: Workers AI API and self-hosted weightsCurrent API, SDK, playground, and access-stage information.

API and provider access

Where to get Clef

CloudflareWorkers AI documentationUse the Workers AI binding or REST API with a state and typed questions.CloudflareModel weights and licenseOfficial model card, Apache 2.0 license and self-hosting instructions.

Availability

Regions and access stage

Available through Workers AI and as downloadable Apache 2.0 weights for self-hosting.

Workers AI runs on Cloudflare's network. The reviewed Clef documentation does not specify country-by-country access or a selectable data-residency region; confirm requirements with Cloudflare.

Check live availability

Data and training

The route matters.

This is a concise reading of the cited provider material, not legal advice. A third-party gateway can have different storage, routing, training, and residency terms from the model maker's direct API.

Read the provider policy

Frequently asked questions

Clef FAQ

What is Clef?

Cloudflare's larger decision model for classifying information and choosing an action without generating a chat response. Clef uses a 27B backbone to evaluate information against questions you define. It returns choices, scores and probabilities that an application can use to route work or request human review.

When was Clef released?

Clef was released on October 1, 2026 according to the cited provider materials.

Where can I access Clef?

Available through Workers AI and as downloadable Apache 2.0 weights for self-hosting. The access routes listed in this guide are Cloudflare.

How much does Clef cost?

$0.24 / 1M input tokens. Workers AI lists input-token pricing only, billed through Neurons. Free daily allowances and other Cloudflare services are separate; self-hosting has its own infrastructure costs.

Where is Clef available?

Available through Workers AI and as downloadable Apache 2.0 weights for self-hosting. Workers AI runs on Cloudflare's network. The reviewed Clef documentation does not specify country-by-country access or a selectable data-residency region; confirm requirements with Cloudflare.

Is my Clef API data used for training?

Cloudflare says Workers AI customer content is not used for training or service improvement without explicit consent. Connected storage services can retain content. Self-hosted deployments follow your own storage and access controls. The policy belongs to the provider route and account terms, so verify it again before production use.

Related comparisons

Head-to-head comparisons

View category →