LocalAI/docs/content/features/decisions.md

+++ disableToc = false title = "Decisions API" weight = 66 url = "/features/decisions/" +++

The Decisions API is a fast, typed decision layer. You send a piece of text (the state) and a set of named questions. A decision model answers each question with a value and a confidence, in one pass. The model does not generate text, so there is nothing to parse and no free-form output to validate.

LocalAI serves it on the /v1/systemone routes. The request and response shapes follow the kev project, and the field names and question types are the same ones Ollama serves on its /v1/systemone endpoint (Ollama 0.35 and later). The wire contract is called SystemOne; the capability a model declares is called decisions. See Compatibility with Ollama for what differs.

OpenAI announced its own Decisions API in limited preview on 2026-09-29. It has no public request or response schema yet, so LocalAI does not serve a /v1/decisions route.

Endpoints

Endpoint	Method	Description
/v1/systemone	POST	Answer all questions in one pass
/v1/systemone/permute	POST	Re-run one choice question under n_perm option orders
/v1/systemone/separate	POST	Answer each question in its own pass

Which route a model can serve depends on its kind:

Model kind	/v1/systemone	/permute and /separate
Decision model (decisions), such as Laya or GLiNER2.5-Decide	Yes	No, returns 400
Zero-shot NER model (token_classify), such as GLiNER2.5	Yes, through the NER path	Yes

Question types

Type	Answer	Fields in the answer
choice	One option out of a named set	choice, probabilities, confidence
noul	Yes, no or unknown for a statement	noul (0 to 1), entities
score	One level on a scale	score, legend, probabilities, confidence

Example

curl http://localhost:8080/v1/systemone -H "Content-Type: application/json" -d '{
  "model": "laya-vllm-cpp",
  "state": "My order arrived broken and I want my money back. This is the second time.",
  "questions": {
    "team": {
      "type": "choice",
      "instructions": "Which team should handle this ticket?",
      "criteria": {
        "billing": "Payments, invoices and refunds",
        "shipping": "Delivery and damaged goods",
        "product": "Questions about how the product works"
      }
    },
    "refund_requested": {
      "type": "noul",
      "instructions": "The customer explicitly asks for a refund"
    },
    "urgency": {
      "type": "score",
      "instructions": "How urgent is this ticket?",
      "criteria": ["not urgent", "somewhat urgent", "urgent", "critical"]
    }
  }
}'

Answers from a decision model carry a confidence value, and the response reports token usage and latency_ms. The NER path does not report token usage.

Choosing a model

A model can serve the Decisions API only if it is a decision model. Declare the usecase in the model config:

name: laya
backend: vllm-cpp
known_usecases:
  - decisions
parameters:
  model: convaiinnovations/laya

decisions is never guessed, and a model that declares it is not listed as a chat, completion or embeddings model. A model that declares usecases without decisions or token_classify gets a 400 from these endpoints that names the missing usecase. A model that declares token_classify and not decisions is served by the zero-shot NER path. A vllm-cpp config that declares no usecases is treated as a decision model, so setups that predate the flag keep working, but a config that declares only chat (as an older laya gallery entry did) now gets the 400 and needs known_usecases: [decisions].

Install one from the gallery and filter on the decisions tag:

Gallery entry	Model	Notes
laya-vllm-cpp	Laya	ModernBERT-large, non-autoregressive, about 800 MB
gliner25-decide-vllm-cpp	GLiNER2.5-Decide	DeBERTa-v3-large with a classification head, about 2 GB
tev1-4b-vllm-cpp	Tev1 4B	Autoregressive Qwen3.5-4B fine-tune that answers with an option letter, about 9.3 GB
tev1-0.8b-vllm-cpp	Tev1 0.8B	Autoregressive Qwen3.5-0.8B fine-tune that answers with an option letter, about 1.8 GB

The engine, [vllm.cpp]({{% relref "features/vllm-cpp" %}}), also supports the kev, CLM and xor decision models. Those checkpoints need a conversion step, so they are not gallery entries yet.

Tev1 is an autoregressive decision model. The engine answers each question by scoring the option letters, so its confidence is the entropy measure Ollama uses. A Tev1 choice or score question accepts at most 24 options (Ollama allows 26), because the model is trained on the letters A to X, and every option needs a nonempty description. The published checkpoints name another architecture in config.json, so the Tev1 gallery entries set engine_args.hf_overrides to load them as Tev1Model (see [Overriding config.json keys]({{% relref "features/vllm-cpp" %}}#overriding-configjson-keys-hf_overrides)). The same model also answers /v1/chat/completions requests.

Request limits

A request is refused with 400 (or 413 for the body size) when:

• the body is larger than 64 KiB,
• state is missing or blank,
• there are no questions, or more than 64,
• a question id is blank,
• a choice question has fewer than 2 options or a blank option key,
• a score question has fewer than 2 levels,
• a noul question has criteria with keys other than "false" and "true".

A noul question may carry criteria with a description for each outcome, for example {"false": "No refund is requested", "true": "The customer requests a refund"}. Some models cap the number of options for a choice or score question. Models that answer with a letter accept at most 26, and Tev1 accepts at most 24. The engine refuses more options than the model supports and the error names the limit.

Compatibility with Ollama

The field names, question types and answer fields are the same as Ollama's /v1/systemone, so a client written for one works against the other for the common case. These behaviors differ:

	Ollama	LocalAI
confidence	1 - H(p) / ln(N), an entropy measure	Computed by the model's pipeline. For kev and Laya it is a normalized margin, so the same probabilities give a different value
Errors	{"error": "message"}	{"error": {"message": "...", "type": "invalid_request"}}
keep_alive	Sets how long the model stays loaded	Accepted and ignored. Model lifetime follows the LocalAI idle and watchdog settings
state given as an object	Serialized as JSON text	Rendered as labeled lines, the way kev does it
noul answer on the NER path	{type, noul}	Also carries entities
Token usage	Full prompt lengths across all questions	Whatever the backend reports; the NER path reports 0

Access control

When authentication is on, the three routes need the decisions feature. It is on by default for every user, like the other API features, and an administrator can turn it off per user.