Images

POST https://api.katara.com/v1/images/generations takes the OpenAI image generation request and returns one image. The model is katara/glm-image@1, which handles posters, illustrations, diagrams and text inside the picture well.

curl https://api.katara.com/v1/images/generations \
  -H "Authorization: Bearer $KATARA_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"katara/glm-image@1","prompt":"A watercolor koi pond at dawn","size":"1280x1280"}'

With the OpenAI client, client.images.generate(model="katara/glm-image@1", prompt="...") works unchanged.

What a request takes

Field
model	katara/glm-image@1.
prompt	What to draw, up to 4,000 characters.
size	WIDTHxHEIGHT, each side 1024 to 2048 pixels and a multiple of 32, at most 4,194,304 pixels in all. The default is 1280x1280; 1568x1056, 1056x1568, 1472x1088, 1088x1472, 1728x960 and 960x1728 suit other shapes. auto takes the default.
quality	hd (the default, about 20 seconds) or standard (5 to 10 seconds). high and auto mean hd; medium and low mean standard.
n	Only 1. Send one request per image.
response_format	Only b64_json.
user	Accepted and not passed on.

Any other field is refused with 400 and code unsupported_parameter, so you never pay for a picture made differently from what you asked. Image editing and reference images are not available.

The reply

{
  "created": 1792252800,
  "data": [{ "b64_json": "iVBORw0KGgo..." }],
  "output_format": "png",
  "usage": { "images": 1 },
  "katara": { "cost_usdc": "0.03", "provider": "managed", "fallback": true, "served": { "model": "katara/glm-image@1", "managed": true } }
}

data[0].b64_json is the image itself, base64-encoded; output_format says whether it is png, jpeg or webp. Katara stores nothing you need to fetch afterwards, so save the image from the reply.

Paying

Every image has one price, known before it is made. /v1/models lists the model with image_generation: true and its image_price.

• A key that pays with USDC is charged the listed image price, 0.03 USDC.
• A key that pays with Account Credits is charged $0.018 per image; katara.cost_usd carries the charge.
• Without a key, the request is paid with x402. The quote is exactly the image price, 0.03 USDC, with the same schemes and settlement as a chat completion.

Images are made by Katara’s own model provider only, never by Katara Community, whatever pays. A request that fails before the image comes back is not charged.

In the chat app, ask Katara Cortex for a picture and it draws one with this model, charged the same way.