> ## Documentation Index
> Fetch the complete documentation index at: https://docs.levanto.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart

> Make your first Levanto Sage decision API call.

Get a decision from Sage in a few minutes.

## Prerequisites

* A Levanto API key (`lv_live_...`) — see [Authentication](/decision-model/authentication) if you don't have one yet

## Endpoint

```text theme={null}
https://sage.levanto.ai
```

## Make a Yes/No decision

Every `/decide` call requires your API key — see [Authentication](/decision-model/authentication) for the header options and error codes.

```bash theme={null}
endpoint="https://sage.levanto.ai"

curl -s \
  -H "Authorization: Bearer $SAGE_API_KEY" \
  -H 'Content-Type: application/json' \
  "$endpoint/decide" -d '{
  "content": "Marketing email draft promotes '\''guaranteed 40% returns'\'' and describes the product as '\''risk-free'\'' for accredited investors.",
  "question": {
    "id": "needs_compliance_review",
    "kind": "yesno",
    "instructions": "Does this copy require compliance review before send?"
  }
}'
```

Example response:

```json theme={null}
{
  "id": "needs_compliance_review",
  "kind": "yesno",
  "result": {
    "probability": 0.92,
    "confidence": 0.84,
    "answer": "yes"
  },
  "meta": { "model": "levanto-sage-v0.5", "latency_ms": 97.4 }
}
```

## Request shape

Every `/decide` request uses this structure:

```json theme={null}
{
  "content": "<content to evaluate>",
  "question": {
    "id": "<stable result id>",
    "kind": "<yesno | choice | scale | sort | tags>",
    "instructions": "<question to answer>"
  }
}
```

Use `content` for the thing being evaluated. Use `question.kind` to select the decision kind and `question.instructions` for the criterion.

<Info>
  Each decision kind has its own size limits (option counts, tag counts, content length). See [Limits](/decision-model/limits) before sending large requests.
</Info>

## Endpoints

| Method | Path            | Auth required | Purpose                                                     |
| ------ | --------------- | ------------- | ----------------------------------------------------------- |
| GET    | `/ready`        | No            | Model readiness — **503** while loading, **200** when ready |
| POST   | `/decide`       | Yes           | One decision                                                |
| POST   | `/decide/batch` | Yes           | Many decisions                                              |

## Next steps

<CardGroup cols={2}>
  <Card title="Yes/No" icon="circle-check" href="/decision-model/yesno">
    Binary questions with probability and confidence.
  </Card>

  <Card title="Choice" icon="list" href="/decision-model/choice">
    Pick the best option from a set.
  </Card>

  <Card title="Use cases" icon="brain" href="/use-cases">
    Routing, guardrails, moderation, and ops triage patterns.
  </Card>
</CardGroup>