Decision models, explained
A decision model reads an input and a set of questions and returns a probability for each answer in one pass, without writing text. Use one when you need a pick, a yes/no or a score, not an essay. Below, four decision models compared using only what each model card says.
When to use a decision model
- Use a decision model for one-pass picks: choose one option from a named list, like which team gets a support ticket.
- Use it for yes/no checks: is this a refund request, does this image contain a chart, does this reply follow policy.
- Use it for scores: rate urgency, relevance or quality on a fixed scale, with a probability for each level.
- Use it for routing: send each request to the right model, tool or queue before any text is generated.
- Use it for screening: filter content, flag risky inputs or rerank search results at high volume.
- Use a chat model instead when you need written output: drafts, explanations, summaries or multi-step reasoning you want to read.
- Check the license and hardware needs on the model card, then test on your own labeled examples before trusting any score.
Compared: what each model card says
| From each model card | JEV-35B ↗ | d3 (Decision 3.0) ↗ | d1-3B ↗ | pplx-decider-v1.1-27b ↗ |
|---|---|---|---|---|
| Made by | AutoTrust | vLLM Semantic Router team | Liquid AI | Perplexity |
| License | Apache-2.0 | Apache-2.0 | Other (LFM 1.0 license): not open-source | Apache-2.0 |
| Size | 35B mixture-of-experts, about 3B active per token | 26.09B; the family spans 0.59B to 26.09B in six models | 3.12B | 27B (Qwen3.8-27B base) |
| Inputs | Text and images | Text or JSON, images and video | Text, JSON and images | Text and images |
| Answer types | Choice, yes/no and score; up to 256 options in one pass | Choice, yes/no and score, several questions per call | Yes/no, choice and score (2 to 10 levels), zero output tokens | Choice and yes/no decisions |
| Speed (author's own claim) | Median 204 ms per request on one B200 | Median 54.4 ms per text request on one AMD MI325X | 8 ms per decision on an RTX 4090 | Not stated |
| Hardware (per card) | About 66 GiB GPU memory in bf16; NVFP4 build about 23 GiB | About 62 to 65 GiB GPU memory per replica | Card reports speeds on an Apple M5 Pro and NVIDIA Jetson boards | About 49 GiB of weights plus working memory; card says access needs authentication |
| Score (author's own claim) | Decision Index 0.3 public suite 59.73, own scoring, not a board entry | Jev Decision Index 0.3.2: 66.3, ranked first on the text board | Decision Index 0.2.1: 48.57, own scoring, not a leaderboard submission | Decision Index 61.56, up from 56.4 for v1 |
Prompts
{"team": {"type": "choice", "instructions": "Which team should handle this [ticket]?", "criteria": {"billing": "[Charges, refunds, invoices]", "technical": "[Setup and faults]", "sales": "[Buying questions]"}}, "urgent": {"type": "noul", "instructions": "Is the customer blocked right now?"}, "quality": {"type": "score", "instructions": "How complete is the request?", "criteria": ["[Missing key details]", "[Some details]", "[Everything needed]"]}}Watch out: Decision models answer only the questions you give them and can be confidently wrong. Benchmark scores are each author's own claim. Check every model's license on its card before commercial use: d1-3B uses Liquid AI's LFM 1.0 license, which is not open-source.