AI bookmark design via API: the tall 1:3 and 1:4 ratios on Sume

A bookmark is a tall strip, and most image models do not offer a ratio that tall. On Sume's catalog only the Ideogram rows list 1:3, and Nano Banana 2 lists 1:4 and 1:8; the tallest ratio on the other rows is shorter than 1:3. So the practical choices for bookmark art are ideogram/ideogram-v4.5 at 1:3 or google/nano-banana-2 at 1:4, then a crop to your printer's template.

Both ratios were run through the request normalizer on origin/main and accepted. The catalog is the authority and can change, so the script below reads the live aspect_ratio lists and shows which rows offer a tall strip today before you build anything on this.

Find the rows with a tall strip

Ask the catalog which models list 1:3 or 1:4 (and the wider 1:8) and print them. This is a free call. It tells you whether a row you want still has the ratio, and keeps your code from sending a value that returns 400 invalid_request with the supported list in details.

If neither ratio exists any more, the fallback is 1:2 on the rows that list it, with a crop. That loses area but keeps the composition.

import os, requests

WANT = ("1:3", "1:4", "1:8", "1:2")
r = requests.get("https://api.sume.com/v1/images/models", timeout=30,
                 headers={"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"})
r.raise_for_status()
for m in r.json()["data"]:
    values = m["supported_parameters"].get("aspect_ratio", {}).get("values", [])
    tall = [v for v in WANT if v in values]
    if tall:
        print(f"{m['id']}: {', '.join(tall)}")

Request the strip

A bookmark design is a vertical composition with the focal point in the upper third and breathing room at the bottom for a tassel hole. Describe that in the prompt, and keep text out of the generation: names and quotes are better added in code, as in the map poster recipe.

Ideogram 4.5 takes quality: low|medium|high, with medium as the default, and resolution: 1K|2K (Sume Image API docs). Nano Banana 2 takes tiers 512, 1K, 2K and 4K. For a strip that will be printed small, 2K on either is a sensible ceiling.

import os, requests

r = requests.post("https://api.sume.com/v1/images", timeout=120, json={
    "model": "ideogram/ideogram-v4.5",
    "prompt": ("Tall vertical bookmark illustration of a lighthouse on a cliff at dusk, "
               "focal point in the upper third, calm empty sea at the bottom, no text"),
    "aspect_ratio": "1:3", "quality": "medium", "resolution": "2K",
}, headers={"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"})
r.raise_for_status()
if r.status_code == 202:
    raise SystemExit("queued: poll the job status_url")
print(r.json()["data"][0]["url"], r.json()["usage"]["cost"])

Crop to the printer template

Bookmark sizes vary by printer, so get the template first and crop to its proportions with the approach in Nano Banana exact pixels. For the full list of rows that offer the extreme ratios, see 1:3 and 3:1 ratios only on Ideogram.

The 1:2 option, listed by Grok among others, is a shorter strip; see 2:1 and 1:2 image models on Sume.