ListLoco — Marketplace-compliant product listing localization

See it work — try it in 60 seconds

No sign-up required to read along. Send a real Amazon English→German listing and get back gate-verified, structured JSON. Same input, same output — every time.

Step 1 · Send a real request

curl -X POST https://listloco.hayasaka.app/localize \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer <YOUR_API_KEY>" \
  --data @examples/amazon-en-de-cordless-drill.json

Request body (examples/amazon-en-de-cordless-drill.json):

{
  "marketplace": "amazon",
  "sourceLang": "en",
  "targetLang": "de",
  "listing": {
    "title": "Cordless drill AB-1200 with 8.5 kg battery and 2 m cable",
    "description": "Cordless drill AB-1200 with a 8.5 kg battery and a 2 m cable.",
    "brand": "Bosch",
    "material": "Metall",
    "size": "M",
    "color": "blue",
    "quantity": 1
  },
  "glossary": { "preserve": ["Bosch"] },
  "dictionary": {
    "cordless": "kabellos",
    "drill": "Bohrmaschine",
    "with": "mit",
    "and": "und",
    "a": "ein",
    "battery": "Akku",
    "cable": "Kabel",
    "blue": "blau"
  }
}

Step 2 · Get back gate-verified JSON

{
  "localized": {
    "title": "kabellos Bohrmaschine AB-1200 mit 8.5 kg Akku und 2 m Kabel",
    "description": "kabellos Bohrmaschine AB-1200 mit ein 8.5 kg Akku und ein 2 m Kabel.",
    "brand": "Bosch",
    "material": "Metall",
    "size": "M",
    "color": "blau",
    "quantity": 1
  },
  "gates": {
    "titleLength": { "pass": true, "violations": [] },
    "bannedWords": { "pass": true, "violations": [] },
    "requiredAttributes": { "pass": true, "violations": [] },
    "preservation": { "pass": true, "violations": [] },
    "glossary": { "pass": true, "violations": [] },
    "backTranslation": { "pass": true, "score": 0, "threshold": 0.3, "enforced": true }
  },
  "violations": [],
  "pass": true
}

Notice the model number AB-1200, the 8.5 kg weight and the 2 m cable survive the round-trip exactly — that is the preservation gate, not luck. When any gate fails, pass is false and the offending rule is listed in violations instead of shipping silently.

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Why ListLoco instead of raw machine translation

Rule compliance

Marketplace rule templates enforce title length limits, banned-word policies, and required attributes — so listings pass review instead of getting suppressed or suspended.

Customer glossary

Brand terms, model numbers, sizes and color names stay consistent across every listing. Your glossary becomes an asset that improves with use.

Deterministic quality gate

Title length, banned words, required attributes, preservation of numbers / model numbers / units, and a back-translation drift score — all checked mechanically before output is returned.

What the quality gate guarantees

Title stays within the Amazon DE character limit.
No banned / prohibited words in the localized copy.
Required category attributes are present.
Numbers, model numbers, and units from the source are preserved exactly (e.g. 42 EU / 8.5 US never disappears).
Back-translation drift is measured to catch meaning loss; failing output is flagged honestly, not returned silently.

Current MVP covers Amazon and the English → German language pair. More marketplaces and language pairs reuse the same rule-template + glossary + quality-gate framework.

Plan	Price	Included listings / mo	Overage / listing
Free	$0	20	$0.15
Starter	$19/mo	150	$0.15
Growth	$59/mo	600	$0.12
Scale	$199/mo	3000	$0.08
Pay-as-you-go	$0.15	—	$0.15

List once. Sell across borders — without getting suppressed.