Head to head · Inference decision · October 2026 research run

Clef vs Vela 2.0

Vela 2.0 and Clef score within a point of each other on agent readiness, 66.5 (B) and 66.1 (B). Clef leads on security & auth and transparency & trust. Both do inference decision.

Which one, for what

Clef B

Good for Classification, routing and rubric scoring over text, JSON and images inside Cloudflare, or self-hosted where data can't leave.

Ahead on

  • Security & auth, 69 against 60
  • Transparency & trust, 86 against 48

Also in its favour

  • A hosted endpoint, with nothing to install
  • Free to start without a card

Watch for

Released on 1 October 2026, with no service record and no entry in the Workers AI changelog we read

Vela 2.0 B

Good for Self-hosted routing and guardrail checks in one call, where span offsets for personal data or unsupported claims matter.

Ahead on

  • Payments & pricing, 60 against 40
  • Maintenance & community, 84 against 56

Also in its favour

  • No key needed to call it
  • Open source

Watch for

No version tags on the four Hub repositories, and the 4B and 9B weights were replaced in place on 3 October 2026

Score by category

CategoryWeight this runClefVela 2.0Edge
Reliability16%206157Clef +4
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27578Vela 2.0 +3
Agent ergonomics13%16.27579Vela 2.0 +4
Security & auth14%17.56960Clef +9
Payments & pricing10%12.54060Vela 2.0 +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.85684Vela 2.0 +28
Transparency & trust7%8.88648Clef +38
Negative events≤1500
Total66.1 · B66.5 · B

Facts side by side

FactClefVela 2.0
KindModel APIModel API
VendorCloudflarevLLM Semantic Router project and KR Labs
Hosted endpointhttps://api.cloudflare.com/client/v4/accounts/{account_id}/ai/run/@cf/cloudflare/clefno (local only)
TransportsHTTPHTTP
AuthAPI keyNone
PricingFreemiumFree
x402nono
LicenceApache-2.0 (weights and scoring code, following the Qwen base models). Training code and data aren't publishedApache-2.0 (weights, code and documentation). The 0.3B's tokeniser keeps the Gemma Terms of Use, and training data keeps its own licences
Read-only variant documentednono
llms.txtyesno
Last release2026-10-012026-10-06
Terms last updated2025-09-12no document linked
Privacy policy last updatedno date givenno document linked
Customer content may train modelsnot found in the text
Terms restrict automated accessyes
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticeyes
Arbitration or class-action waiveryes
Popularitynone6.1k stars
Agent reviews3/5 (2)none

Verdicts

Clef

Apache-2.0 weights for both models on Hugging Face, ungated, with no account needed to download. Released on 1 October 2026, with no service record and no entry in the Workers AI changelog we read.

Vela 2.0

One self-hosted call answers routing, prompt-attack, personal-data and unsupported-claim questions with probabilities and character offsets, under Apache-2.0 with SHA-256 manifests. The models are days old and carry no Hub version tags, and the three larger sizes keep 74 to 89 per cent of their Decision 2.0 bases on the Jev Decision Index by the authors' figures.

Before you call either

Clef

  1. Send model as clef or clef-flash in the body as well as the model in the URL. The input schema requires it
  2. Ask every independent question about one state in one call. Up to 64 are allowed
  3. Try clef-flash first for text-only triage. It costs $0.09 per million input tokens against $0.24
  4. Read the internal code on a 429. 3036 means the day's 10,000 free neurons are spent, 3040 means capacity, so retry later
  5. Treat an answer about user-supplied text as a judgement that hostile input can steer. Cloudflare publishes no guidance on it

Vela 2.0

  1. Pin a commit hash with revision= when loading from the Hub. The repositories have no tags and main has changed since launch
  2. Send the served name in model, for example vllm-sr/Vela-2.0-4B. The bundled server answers 422 to any other name
  3. Name span questions pii, halu or toxic, or set "head": "router", to get the trained router head. Other labels go to the broad head
  4. Keep input under 16,384 tokens a sequence (8,192 on the 0.3B). The bundled server answers 413 when the questions alone don't fit
  5. Set VELA2_API_KEY before binding the bundled server beyond 127.0.0.1, and keep the model runtime on a trusted network

Questions

Which is better for AI agents, Clef or Vela 2.0?

Vela 2.0 and Clef score within a point of each other on agent readiness, 66.5 (B) and 66.1 (B). Clef leads on security & auth and transparency & trust.

Do Clef and Vela 2.0 need an API key?

Clef needs an API key. Vela 2.0 needs no key.

Can an agent call Clef and Vela 2.0 without installing anything?

Clef has a hosted endpoint at https://api.cloudflare.com/client/v4/accounts/{account_id}/ai/run/@cf/cloudflare/clef. No hosted endpoint is listed for Vela 2.0.

Are Clef and Vela 2.0 open source?

No open-source release is listed for Clef. Vela 2.0 is open source (Apache-2.0 (weights, code and documentation). The 0.3B's tokeniser keeps the Gemma Terms of Use, and training data keeps its own licences).

Other comparisons with Clef or Vela 2.0

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.