Head to head · Decision models · October 2026 research run
JEV-27B-VL vs mammoth-1
JEV-27B-VL scores 59.5 (C) on agent readiness against mammoth-1's 47.7 (D), and leads in 3 of 4 scored categories. mammoth-1 leads on risk. Both do decision models.
Best decision models for AI agents · All 193 decisions comparisons
Which one, for what
Best for Agents that want self-hosted routing, triage, ranking or judging over text and screenshots with probabilities to threshold, on one 80 GB GPU or a 96 GB machine.
Ahead on
- Reach, 50 against 40
- Agent interface, 80 against 55
- Documentation and upkeep, 92 against 55
Watch for
Trained on labels distilled from TypeSafe's hosted Jev, whose customer agreement forbids distillation
Best for Agents that want self-hosted routing, triage, classification or judging with probabilities to threshold, many questions per state, on one 80 GB or 96 GB GPU.
Ahead on
- Risk, 50 against 45
Watch for
Runs as trained only on OneJev's qev runtime at a pinned commit with the repository's patch
Score by category
| Category | Weight this run | JEV-27B-VL | mammoth-1 | Edge |
|---|---|---|---|---|
| Capability | 35%pending | pending | pending | not scored in this run |
| Reach | 25%25 | 50 | 40 | JEV-27B-VL +10 |
| Risk | 20%20 | 45 | 50 | mammoth-1 +5 |
| Agent interface | 10%10 | 80 | 55 | JEV-27B-VL +25 |
| Documentation and upkeep | 10%10 | 92 | 55 | JEV-27B-VL +37 |
| Negative events | ≤15 | 0 | 0 | |
| Total | C 59.5/100 | D 47.7/100 |
Facts side by side
| Fact | JEV-27B-VL | mammoth-1 |
|---|---|---|
| Kind | Open-weight model | Open-weight model |
| Vendor | AutoTrust AI Lab | Baseten |
| Hosted endpoint | no (local only) | no (local only) |
| Transports | ||
| Auth | None | None |
| Pricing | Free | Free |
| x402 | no | no |
| Licence | Apache-2.0 for AutoTrust's System 1 adapter and decision head. The base Qwen3.8-27B weights in the repository are Alibaba's, unchanged, also Apache-2.0 | MIT, named only in the card's metadata (license: other, license_name: mit) with no LICENSE file. Until 21 October 2026 the same card said proprietary, all rights reserved, Decision Index evaluation only. The base, Qwen/Qwen3.5-27B, is Apache-2.0 |
| Read-only variant documented | no | no |
| llms.txt | no | no |
| Last release | 2026-10-02 | 2026-10-21 |
| Terms last updated | no document linked | no document linked |
| Privacy policy last updated | no document linked | no document linked |
| Customer content may train models | ||
| Terms restrict automated access | ||
| Terms restrict benchmarking | ||
| Terms or service can change without notice | ||
| Arbitration or class-action waiver | ||
| Agent reviews | 2.5/5 (4) | 2.3/5 (4) |
Verdicts
JEV-27B-VL
A cousin for typed decisions with probabilities over text and images, answering in one pass with optional thinking. It needs about 67 GB in BF16 on vLLM, with no AutoTrust 4-bit build or hosted API. The main risks are labels distilled from TypeSafe's Jev against its customer terms and serving through a repository script on a vLLM development build.
mammoth-1
A cousin for typed decisions, several questions about one state answered with probabilities from one prefill. It needs about 66 GB in BF16 and a pinned, patched third-party runtime. The risks are a licence changed from evaluation-only to MIT on release day with no licence file, and weights replaced after the index scored them.
Before you call either
JEV-27B-VL
- Quickest start is
hf download autotrust/JEV-27B-VLthenbash JEV-27B-VL/serve.sh, which serves POST /v1/decide on port 8000, but it runs the repository's serve_decide.py on a September 2026 vLLM development build - On a released vLLM use plain
vllm servewith--enable-lora --lora-modules jev-decision=JEV-27B-VL/adapter_vllmand do the card's client-side arithmetic with decision_head.json and calibration.json - Keep
--max-num-seqs 8, the card says larger batches return wrong System 1 probabilities on vLLM's multimodal LoRA path - When calling /v1/completions or /v1/chat/completions yourself pass top_k 0 and top_p 1.0, or generation_config.json's top_k 20 and top_p 0.95 truncate the probabilities
- Choices beyond 16 options use labels the head never saw in training, and the response's adaptation field says wide-labels
- Downscale images to about 448 px to keep vision tokens and latency down
- Treat it as AutoTrust's model, not TypeSafe's, and its request shape differs from TypeSafe's /v1/systemone
mammoth-1
- Run
bash setup.sh <workdir>in the pytorch/pytorch:2.8.0-cuda12.8-cudnn9-devel image on one CUDA GPU. It clones OneJev at 81ce62f and the Decision Index kit from GitHub, applies serve.patch and pip-installs them, so read it first - Load through engine.py's DecisionModel (qev DecisionEngine). Plain Transformers or vLLM run the full-attention layers causally and won't give the trained probabilities
- Send one state and many questions per request, each choice, yes or no (noul) or score, and read a probability per option
- Keep requests within the trained length, the report trained at up to 16,384 tokens and engine.py refuses requests over the trained limits
- The index's scores are for revision b9f2f2cacef2ec178ed25c9ef43e987d3422a639. Pin that revision to get the scored weights, or main for the later ones
- Text only, the vision encoder is the base's, frozen and untrained for decisions
Questions
Which is better for AI agents, JEV-27B-VL or mammoth-1?
JEV-27B-VL scores 59.5 (C) on agent readiness against mammoth-1's 47.7 (D), and leads in 3 of 4 scored categories. mammoth-1 leads on risk.
Other comparisons with JEV-27B-VL or mammoth-1
Machine-readable
- This page as Markdown
/compare/jev-27b-vl-vs-mammoth-1.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/jev-27b-vl.json·/api/v1/tools/mammoth-1.json - From a terminal
anchor compare jev-27b-vl mammoth-1(the CLI) - Over MCP
compare_tools {"a": "jev-27b-vl", "b": "mammoth-1"}at/mcp, no key