Nova Canvas boto3 read timeout vs Sume's 30 second wait and 202

A Nova Canvas call that times out in boto3 and a Sume call that returns 202 look like the same bug. They are not. One is a client timeout that you set; the other is a documented answer that tells you to poll.

What each side says

Handle the three answers

On Sume, 200 means images are in the body, 202 means the job is still running, and 502 means it failed. Do not raise a timeout on 202. Poll status_url until the job is terminal, then read result_url. You can also pass mode: "async" to skip the wait, or mode: "webhook" with a webhook_url.

import os, time, requests

H = {"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"}
r = requests.post("https://api.sume.com/v1/images", headers=H, timeout=60, json={
    "model": "ideogram/ideogram-v4.5", "quality": "high", "resolution": "2K",
    "prompt": "Add soft window light from the left. Keep the product unchanged.",
    "input_references": [{"type": "image_url", "image_url": {"url": "https://example.com/lamp.jpg"}}]})
if r.status_code == 200:
    print(r.json()["data"][0]["url"])
elif r.status_code == 202:
    job = r.json().get("job", r.json())
    while True:
        s = requests.get(job["status_url"], headers=H, timeout=30).json()
        if s.get("status") in ("completed", "failed"):
            break
        time.sleep(3)
    print(s.get("status"), job["result_url"])
else:
    print(r.status_code, r.json()["error"]["next_action"])

The envelope field names come from the Sume docs on jobs and results; check them against a real 202 before you ship.