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# Aplomb 1

> Answers yes/no, choice, score and tool questions about text, JSON, images, video and audio in up to 1M tokens, and can tell when the input lacks the answer.

![Aplomb 1](https://media.empiriolabs.ai/model-logos/empiriolabs.png)

[EmpirioLabs](/providers/empiriolabs) · Decision

`POST /v1/decisions`

Answers yes/no, choice, score and tool questions about text, JSON, images, video and audio in up to 1M tokens, and can tell when the input lacks the answer.

## At a glance

| Field               | Value                                                                                                                                        |
| ------------------- | -------------------------------------------------------------------------------------------------------------------------------------------- |
| Model id            | `aplomb-1`                                                                                                                                   |
| Model release date  | 2026-09-29                                                                                                                                   |
| Input modalities    | Text, Image, Video, Audio                                                                                                                    |
| Output modalities   | Decision                                                                                                                                     |
| Context window      | 1M                                                                                                                                           |
| Weight precision    | BF16 weights                                                                                                                                 |
| Features            | classification, calibrated\_probabilities, tool\_selection, abstain, long\_context, vision, video, audio\_in, multimodal                     |
| Native inference    | Yes                                                                                                                                          |
| New                 | Yes                                                                                                                                          |
| Supported endpoints | `POST /v1/decisions`, `POST /v1/chat/completions`, `POST /v1/responses`, `POST /v1/messages`, `POST /v1beta/models/aplomb-1:generateContent` |
| Alternate model ids | `aplomb`, `empiriolabs/aplomb-1`, `empiriolabs/aplomb`                                                                                       |

## Pricing

| Charge | Spec                    | Rate   |
| ------ | ----------------------- | ------ |
| Input  | per 1M prompt tokens    | \$0.02 |
| Output | per 1M generated tokens | Free   |

## Example request

```bash
curl https://api.empiriolabs.ai/v1/decisions \
  -H 'Authorization: Bearer $EMPIRIOLABS_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"model": "aplomb-1", "state": "Customer: I was charged twice for my subscription this month and I need a refund today.", "questions": {"is_urgent": {"type": "noul", "instructions": "Does the customer need a resolution today?"}, "department": {"type": "choice", "instructions": "Which team should handle this message?", "criteria": {"billing": null, "technical": null, "sales": null}}}}'
```

## Parameters

| Parameter      | Type | Required | Default  | Description                                                                                                                                                                      |
| -------------- | ---- | -------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `long_context` | enum | no       | `"fast"` | How a state longer than 131,072 tokens is read: fast (the default) answers in seconds, full reads every token. Shorter states are always read in full. · Allowed: `fast`, `full` |

## Notes

**Requests**

Send content in `state` (a string, a JSON object, or an array) and 1 to 128 questions in `questions` to `POST /v1/decisions`. Each question is answered on its own, with probabilities and a confidence value. No text is generated.

**Question types**

* `noul`: yes or no, answered with the probability of yes.
* `choice`: one of 2 to 255 options, answered with the chosen option and the full distribution.
* `score`: 2 to 10 ordered levels, answered with the expected level and the distribution.
* `tool`: which of 1 to 254 function tools to call, with distributions over its enum and boolean arguments.

**Not in the state**

Add `"abstain": true` to a `noul`, `choice` or `score` question to let the model say the state does not contain the answer. The answer then includes `abstain`, the probability of that outcome, and the rest of the answer assumes the state does contain it.

**Limits**

* The state plus the longest question: up to 1,000,000 tokens.
* At most 512 evaluated questions per request. A tool question counts as one plus one per enum or boolean argument.
* Media: up to 16 images (20 MB each), 8 audio clips (25 MB and 10 minutes each) and 4 videos (100 MB and 10 minutes each), as public HTTPS URLs or inline base64.

**Decision Index**

On our run of the official Decision Index 0.2.1 kit (October 5, 2026), Aplomb 1 scores 44.86 across 38 public benchmarks in five areas, with all 150,317 scoreable requests answered. This is not an entry on the published board. Aplomb 1's training data included the public train splits of WinoGrande and ContractNLI, two of the 38 benchmarks in the index. We could not fully verify that index items were excluded from the earliest training data. The comparison with other models is in the [launch post](https://empiriolabs.ai/blog/introducing-aplomb-1).

**Billing**

Input tokens only: the state once per request, each question's own text, and each media item's tokens. Output is always zero.

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*Machine-readable schema:* `GET https://api.empiriolabs.ai/v1/models/aplomb-1`.