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

JEV-27B-VL C

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

mammoth-1 D

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

CategoryWeight this runJEV-27B-VLmammoth-1Edge
Capability35%pendingpendingpendingnot scored in this run
Reach25%255040JEV-27B-VL +10
Risk20%204550mammoth-1 +5
Agent interface10%108055JEV-27B-VL +25
Documentation and upkeep10%109255JEV-27B-VL +37
Negative events≤1500
TotalC 59.5/100D 47.7/100

Facts side by side

FactJEV-27B-VLmammoth-1
KindOpen-weight modelOpen-weight model
VendorAutoTrust AI LabBaseten
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFree
x402nono
LicenceApache-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-2.0MIT, 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 documentednono
llms.txtnono
Last release2026-10-022026-10-21
Terms last updatedno document linkedno document linked
Privacy policy last updatedno document linkedno 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 reviews2.5/5 (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

  1. Quickest start is hf download autotrust/JEV-27B-VL then bash 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
  2. On a released vLLM use plain vllm serve with --enable-lora --lora-modules jev-decision=JEV-27B-VL/adapter_vllm and do the card's client-side arithmetic with decision_head.json and calibration.json
  3. Keep --max-num-seqs 8, the card says larger batches return wrong System 1 probabilities on vLLM's multimodal LoRA path
  4. 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
  5. Choices beyond 16 options use labels the head never saw in training, and the response's adaptation field says wide-labels
  6. Downscale images to about 448 px to keep vision tokens and latency down
  7. Treat it as AutoTrust's model, not TypeSafe's, and its request shape differs from TypeSafe's /v1/systemone

mammoth-1

  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
  2. 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
  3. Send one state and many questions per request, each choice, yes or no (noul) or score, and read a probability per option
  4. Keep requests within the trained length, the report trained at up to 16,384 tokens and engine.py refuses requests over the trained limits
  5. The index's scores are for revision b9f2f2cacef2ec178ed25c9ef43e987d3422a639. Pin that revision to get the scored weights, or main for the later ones
  6. 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

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