Image Input

An image is a content part inside a chat message. content becomes an array: a text part for your words and an image_url part for the picture.

{
  "type": "image_url",
  "image_url": {
    "url": "https://static.example.org/chart.png",
    "detail": "auto"
  }
}

url is required; detail is an optional hint about how closely to look.

Three Ways to Supply It

An https URL. The gateway fetches it. No credentials, no private or loopback hosts.
A data URL. data:image/png;base64,<bytes>. Nothing is fetched.
Raw base64 plus media_type. The gateway builds the data URL.

There is no file_id for images. Send the image each time.

Model Support

The model must advertise supports_image_inputs; otherwise the request is rejected. The catalog changes, so select at runtime:

curl https://app.trynito.ai/v1/models \
  -H "Authorization: Bearer $NITO_API_KEY"

Multipart Limits

A chat request can also carry images as multipart form parts alongside a JSON request field. That path enforces:

Limit	Value
Formats	PNG, JPEG, WebP
Images per request	10
Size per image	5 MiB
Combined size	50 MiB
Long edge	2048 px

Example

curl https://app.trynito.ai/v1/chat/completions \
  -H "Authorization: Bearer $NITO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen/qwen3-vl-235b-a22b-instruct",
    "messages": [
      {
        "role": "user",
        "content": [
          { "type": "text", "text": "What does this chart show? Summarize the trend." },
          {
            "type": "image_url",
            "image_url": {
              "url": "https://static.example.org/quarterly-revenue.png",
              "detail": "auto"
            }
          }
        ]
      }
    ]
  }'

Inline bytes instead of a URL:

{
  "type": "image_url",
  "image_url": { "url": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA..." }
}

Raw base64 with a media type:

{
  "type": "image_url",
  "image_url": { "url": "iVBORw0KGgoAAAANSUhEUgAA...", "media_type": "image/png"     }
}

The response is an ordinary chat completion; the model’s reading comes back as text. Documents take a different part and path: PDF and Document Input.

Multimodal

Overview.

PDF and Document Input

Documents in chat.

How the API Works

The request lifecycle.

Basics

Features

Server-Side Tools

Multimodal

Best Practices

SDKs

API Reference

Image Input

Three Ways to Supply It

Model Support

Multipart Limits

Example

Multimodal

PDF and Document Input

How the API Works

​Three Ways to Supply It

​Model Support

​Multipart Limits

​Example

​Related

Multimodal

PDF and Document Input

How the API Works

Three Ways to Supply It

Model Support

Multipart Limits

Example

Related