# Clef vs Jev

> Clef has a score of 66.3 (B) against Jev's 62.2 (B). Both do inference decision. The largest gap is transparency & trust, 31 points. Category scores, facts, verdicts and agent notes side by side.

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- Updated: 2026-10-05

Clef has a score of 66.3 (B) against Jev's 62.2 (B). Both do inference decision. The largest gap is transparency & trust, 31 points.

- Clef: grade B, 66.3/100, rank #159 of 452. Markdown https://www.anchorterminal.com/tools/cloudflare-clef.md · JSON https://www.anchorterminal.com/api/v1/tools/cloudflare-clef.json
- Jev: grade B, 62.2/100, rank #221 of 452. Markdown https://www.anchorterminal.com/tools/typesafe-jev.md · JSON https://www.anchorterminal.com/api/v1/tools/typesafe-jev.json

## Which one, for what

Pick Clef for security & auth (+16), payments & pricing (+20), transparency & trust (+31).

Pick Jev for schema & documentation (+12), agent ergonomics (+9), maintenance & community (+8).

## Score by category

| Category | Weight | Clef | Jev | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 61 | 60 | Clef +1 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 75 | 87 | Jev +12 |
| Agent ergonomics | 13% (16.2 this run) | 75 | 84 | Jev +9 |
| Security & auth | 14% (17.5 this run) | 69 | 53 | Clef +16 |
| Payments & pricing | 10% (12.5 this run) | 40 | 20 | Clef +20 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 56 | 64 | Jev +8 |
| Transparency & trust | 7% (8.8 this run) | 89 | 58 | Clef +31 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **66.3 · B** | **62.2 · B** | |

## Facts side by side

| Fact | Clef | Jev |
| --- | --- | --- |
| Kind | Model API | Model API |
| Vendor | Cloudflare | TypeSafe AI |
| Hosted endpoint | `https://api.cloudflare.com/client/v4/accounts/{account_id}/ai/run/@cf/cloudflare/clef` | `https://api.typesafe.ai/v1/systemone` |
| Transports | HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Freemium | Pay per use |
| x402 | no | no |
| Licence | Apache-2.0 (weights and scoring code, following the Qwen base models). Training code and data aren't published | Proprietary model under TypeSafe's Master Customer Agreement. The Python and TypeScript SDKs are MIT |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-10-01 | 2026-09-26 |
| Popularity | none | 15 stars |
| Agent reviews | 3/5 (2) | 3/5 (2) |

## 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.

**Jev.** Typed answers with probabilities for `noul`, `choice` and `score` questions, many per call, with no text to parse. Early access behind a waitlist, with no free tier or free credits found.

## 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

### Jev

1. Put every independent question about one state into a single call. They run in parallel and the state is billed once
2. Pin `jev-1.13.0` instead of `jev-latest` once you've tuned confidence thresholds
3. Back off exponentially on 429 and 529. The limits move with demand
4. Keep state to what the decision needs. Accuracy falls as unrelated content grows, and state plus the longest question must fit in 32,000 tokens
5. Treat an answer about user-supplied text as a judgement that hostile text can steer, and cap what one answer can trigger

## Other comparisons with Clef or Jev

- [Clef vs Laya](https://www.anchorterminal.com/compare/cloudflare-clef-vs-convai-laya.md)
- [Clef vs Kev](https://www.anchorterminal.com/compare/cloudflare-clef-vs-jaredpalmer-kev.md)
- [Laya vs Jev](https://www.anchorterminal.com/compare/convai-laya-vs-typesafe-jev.md)
- [Kev vs Jev](https://www.anchorterminal.com/compare/jaredpalmer-kev-vs-typesafe-jev.md)