GPT Image 2.5 quality auto reserves max on Sume: pin quality

On Sume's GPT Image 2.5 models, quality: auto reserves the max price, and auto size reserves the output token upper bound. If you know the tier you need, name it, and the amount held before the job runs gets smaller.

OpenAI's guide lists the quality values as low, medium, high, xhigh, max and auto. Sume defaults to high when the field is omitted.

What the docs state

Figures from Sume's Image API page, read 2026-10-03. Sume prices are before Sume's own pricing is applied, as the page says.

What the hold means

Before a paid job runs, the platform reserves funds against its worst case. Sume's errors and credits docs cover what happens when a wallet cannot cover a request, so a large reservation matters most for small balances or many parallel jobs. The docs state the reservation rule for auto; they do not publish a hold amount for a given request, so read the live cost from the response rather than computing it here.

A request that pins quality

Setting quality removes the max reservation. For size, the docs allow custom pixels through image_size: both edges multiples of 16, a maximum edge of 3840, an aspect ratio of at most 3:1, and 655,360 to 8,294,400 pixels. The docs excerpt used here does not show the value's JSON shape, so read it from the model's catalog descriptor before sending one. The request below pins quality only.

import os, requests

body = {
    "model": "openai/gpt-image-2.5",
    "prompt": "a ceramic mug on a wooden desk, morning light",
    "quality": "medium",
}
r = requests.post("https://api.sume.com/v1/images",
                  headers={"Authorization": "Bearer " + os.environ["SUME_API_KEY"]},
                  json=body, timeout=60)
print(r.status_code, r.json())

Choosing a tier

A starting rule, not a benchmark.

• Drafts: low or medium. You are judging composition.
• Finals: high, the default, unless a close look shows a flaw that a higher tier fixes.
• xhigh and max: only after a side by side shows a visible gain on your content. The 1024 by 1024 figures above show max output costing more than twice xhigh.
• Leave auto for cases where you want the model to decide and your balance can carry the reservation.