Image inputs

Add an image_url content part to a user message, pointing at an HTTPS URL or holding the image as a base64 data: URL. The examples use openai/gpt-6-luna; replace it with a model whose endpoints accept image input (see Route to vision-capable endpoints).

Send an image by URL

curl -X POST "https://api.numes.ai/api/v1/chat/completions" \  -H "Authorization: Bearer $NUMES_API_KEY" \  -H "Content-Type: application/json" \  -d '{    "model": "openai/gpt-6-luna",    "messages": [      {        "role": "user",        "content": [          {            "type": "text",            "text": "Transcribe the total and the date from this receipt."          },          {            "type": "image_url",            "image_url": {              "url": "https://example.com/images/receipt.jpg"            }          }        ]      }    ]  }'

The URL must be publicly reachable over HTTPS when the request runs. Signed URLs work while they're valid. Images on localhost or a private network can't be fetched; send them inline instead.

Send a local image as base64

Send a data: URL with the media type image/png, image/jpeg, image/gif or image/webp, matching the actual file, and standard (not URL-safe) base64:

import base64import osfrom pathlib import Path​from openai import OpenAI​MEDIA_TYPES = {".png": "image/png", ".jpg": "image/jpeg", ".jpeg": "image/jpeg", ".gif": "image/gif", ".webp": "image/webp"}​def image_data_url(path: str) -> str:    file = Path(path)    encoded = base64.b64encode(file.read_bytes()).decode("ascii")    return f"data:{MEDIA_TYPES[file.suffix.lower()]};base64,{encoded}"​client = OpenAI(base_url="https://api.numes.ai/api/v1", api_key=os.environ["NUMES_API_KEY"])​completion = client.chat.completions.create(    model="openai/gpt-6-luna",    messages=[        {            "role": "user",            "content": [                {"type": "text", "text": "Describe this chart in two sentences."},                {"type": "image_url", "image_url": {"url": image_data_url("chart.png")}},            ],        }    ],)print(completion.choices[0].message.content)

Inline images count toward the 10 MiB chat body limit, and base64 adds about a third to their size. Keep inline images under about 7.5 MiB in total, or send HTTPS URLs.

The image_url part

Add one part per image; images reach the model in the order you list them. The model doesn't see which sentence an image sat next to, so refer to images by position ("the first screenshot"). Images in earlier turns that you resend are sent, and billed, again.

Route to vision-capable endpoints

Routing considers only endpoints whose input_modalities include image. Check a model's endpoints before you send images:

curl "https://api.numes.ai/api/v1/models/author/vision-model/endpoints" \  -H "Authorization: Bearer $NUMES_API_KEY"

You can combine image input with the usual routing preferences.

Limits

See Sending media for the rules every media URL follows.

Billing

Endpoints price images either per image, reported as input_images in usage, or as prompt tokens. Text tokens and any per-request price apply as usual. pricing.image in GET /models shows the lowest image rate of the model's representative endpoint. See Usage accounting.

Troubleshooting

Image problems return 400 invalid_request, and the message names the failing part, such as messages[0].content[1].image_url.url.

Next steps