Full Example (Python)

pip install requests

import os, sys, time, requests

BASE = os.environ.get("GENLOOK_BASE_URL", "https://api.genlook.app/tryon/v1")
API_KEY = os.environ["GENLOOK_API_KEY"]  # required

session = requests.Session()
session.headers["x-api-key"] = API_KEY


# ── 1. Upload the customer photo once ───────────────────────

def upload_customer(file_path: str, *, crop: bool = True) -> str:
    """Returns an imageId you can reuse across many generations."""
    with open(file_path, "rb") as f:
        r = session.post(
            f"{BASE}/images/upload",
            files={"file": (os.path.basename(file_path), f, "image/jpeg")},
            data={"crop": "true" if crop else "false"},
        )
    r.raise_for_status()
    return r.json()["imageId"]


# ── 2. Try-on with ref-first, upsert-on-miss ────────────────

def try_on(image_id: str, external_id: str, full_payload: dict) -> str:
    """Reference the product if it's cached; full inline upsert if it's not.

    `full_payload` is the dict you'd pass as the single `products[]` item to upsert: at
    minimum `{title, description, images: [{source: {url|fileKey}}, ...]}`. The function
    adds `externalId` for you.
    """
    # First attempt: pure reference (cheap)
    r = session.post(
        f"{BASE}/try-on",
        json={
            "products": [{"externalId": external_id}],
            "person": {"image": {"source": {"id": image_id}}},
        },
    )
    if r.status_code == 404 and r.json().get("code") == "PRODUCT_NOT_FOUND":
        # TTL expired (or first time we've seen this externalId). Upsert + retry.
        r = session.post(
            f"{BASE}/try-on",
            json={
                "products": [{**full_payload, "externalId": external_id}],
                "person": {"image": {"source": {"id": image_id}}},
            },
        )
    r.raise_for_status()
    body = r.json()
    print(f"Generation queued: {body['generationId']}  product={body['productExternalId']}")
    return body["generationId"]


# ── 3. Poll until done ──────────────────────────────────────

def poll(generation_id: str, *, timeout_s: int = 180) -> dict:
    deadline = time.time() + timeout_s
    while time.time() < deadline:
        r = session.get(f"{BASE}/generations/{generation_id}")
        r.raise_for_status()
        data = r.json()
        status = data["status"]
        print(f"  {int(time.time() - (deadline - timeout_s)):3d}s  {status}")
        if status == "COMPLETED":
            return data
        if status == "FAILED":
            sys.exit(f"Generation failed: {data.get('errorMessage')}")
        time.sleep(2)
    sys.exit("Timed out")


# ── Run it ──────────────────────────────────────────────────

if __name__ == "__main__":
    CUSTOMER_PHOTO = "./customer.jpg"
    PRODUCT = {
        "title": "Red tee",
        "description": "Soft cotton regular fit",
        "images": [{"source": {"url": "https://cdn.example.com/red-tee.jpg"}}],
    }
    EXTERNAL_ID = "shirt-42"

    image_id = upload_customer(CUSTOMER_PHOTO)
    print(f"Customer uploaded: {image_id}")

    # Try a generation. Works on a cold start (will upsert) and on subsequent
    # calls (will just reference). Idempotent either way.
    gen_id = try_on(image_id, EXTERNAL_ID, PRODUCT)
    result = poll(gen_id)
    print(f"\n→ {result['resultImageUrl']}")

export GENLOOK_API_KEY=gk_your_api_key
python tryon_demo.py

Customer uploaded: ephemeral/customer/ttl-7d/acc_abc/20260512-9f86d.jpeg
Generation queued: cm8gen456xyz  product=shirt-42
  0s  PENDING
  2s  PROCESSING
 14s  COMPLETED

→ https://storage.googleapis.com/...