Get started with ListLoco in minutes

Step 0 — Try it free, no signup

Before subscribing, test with the free POST /try endpoint — no API key required. Send any listing and get a gate-verified result back in seconds.

curl -X POST https://listloco.hayasaka.app/try \
  -H "Content-Type: application/json" \
  -d '{"listing":{"title":"Cordless drill AB-1200","brand":"Bosch"}}'

The free trial is rate-limited. For full EN→DE localization and higher quota, subscribe on RapidAPI. See listloco.hayasaka.app/try for details.

Using ListLoco from RapidAPI

Subscribe on RapidAPI to get your X-RapidAPI-Key, then paste it in place of <YOUR_RAPIDAPI_KEY> in the snippet for your language. All three examples call https://listloco.p.rapidapi.com/localize and return the same gate-verified JSON — choose whichever runtime fits your stack.

Subscribe on RapidAPI See full request body

Python (requests)

import requests

payload = {
    "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
    },
    "dictionary": {
        "cordless": "kabellos",
        "drill": "Bohrmaschine",
        "with": "mit",
        "and": "und",
        "a": "ein",
        "battery": "Akku",
        "cable": "Kabel",
        "blue": "blau"
    }
}
response = requests.post(
    "https://listloco.p.rapidapi.com/localize",
    json=payload,
    headers={
        "X-RapidAPI-Key": "<YOUR_RAPIDAPI_KEY>",
        "X-RapidAPI-Host": "listloco.p.rapidapi.com",
        "Content-Type": "application/json"
    }
)
print(response.json())

Node.js (fetch)

const body = {
  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
  },
  dictionary: {
    cordless: "kabellos",
    drill: "Bohrmaschine",
    with: "mit",
    and: "und",
    a: "ein",
    battery: "Akku",
    cable: "Kabel",
    blue: "blau"
  }
};

const response = await fetch("https://listloco.p.rapidapi.com/localize", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "X-RapidAPI-Key": "<YOUR_RAPIDAPI_KEY>",
    "X-RapidAPI-Host": "listloco.p.rapidapi.com"
  },
  body: JSON.stringify(body)
});
const result = await response.json();
console.log(result);

PHP

<?php
$curl = curl_init();
curl_setopt_array($curl, [
    CURLOPT_URL => "https://listloco.p.rapidapi.com/localize",
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        "Content-Type: application/json",
        "X-RapidAPI-Key: <YOUR_RAPIDAPI_KEY>",
        "X-RapidAPI-Host: listloco.p.rapidapi.com"
    ],
    CURLOPT_POSTFIELDS => json_encode([
        "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
        ],
        "dictionary" => [
            "cordless" => "kabellos",
            "drill" => "Bohrmaschine",
            "with" => "mit",
            "and" => "und",
            "a" => "ein",
            "battery" => "Akku",
            "cable" => "Kabel",
            "blue" => "blau"
        ]
    ])
]);
$response = curl_exec($curl);
curl_close($curl);
echo $response;

Prerequisites

ListLoco is distributed via RapidAPI. Subscribe to the free or paid plan on RapidAPI and copy your X-RapidAPI-Key from the dashboard. No separate backend credential is needed for the RapidAPI path.

Use case: an English-language listing for Amazon.com that you want to publish on Amazon DE. The API enforces Amazon Germany's title character limit, banned keyword list, required attributes, and number/model-number preservation in a single deterministic pass — the same rules that cause suppressed listings when violated. The output is English to German localized copy that is ready to verify before submission.

1 Via RapidAPI (recommended)

curl -s -X POST "https://listloco.p.rapidapi.com/localize" \
  -H "Content-Type: application/json" \
  -H "X-RapidAPI-Key: <YOUR_RAPIDAPI_KEY>" \
  -H "X-RapidAPI-Host: listloco.p.rapidapi.com" \
  --data '{
    "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"
    }
  }'

2 Direct API (self-hosted / local dev)

curl -s -X POST https://listloco.hayasaka.app/localize \
  -H "Content-Type: application/json" \
  -H "x-api-key: <YOUR_API_KEY>" \
  --data '{
    "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"
    }
  }'

Request body reference

All fields are required unless marked optional. The marketplace, sourceLang, and targetLang select the rule template — currently only "amazon" / "en" / "de" is supported. The glossary.preserve array locks brand names and model numbers so they survive translation and the preservation gate does not flag them as corrupted. The dictionary map provides known word translations and is the primary mechanism for consistent Amazon DE listing localization from English to German.

{
  "marketplace": "amazon",          // required — rule template selector
  "sourceLang": "en",               // required — source language code
  "targetLang": "de",               // required — target language code
  "listing": {
    "title": "...",                 // required — plain-text title
    "description": "...",           // required — plain-text description
    "brand": "...",                 // required — brand name
    "material": "...",              // required — material
    "size": "...",                  // required — size
    "color": "...",                 // required — color
    "quantity": 1                   // required — integer quantity
  },
  "glossary": {
    "preserve": ["Bosch", "AB-1200"] // optional — strings never altered by translation
  },
  "dictionary": {                   // optional — source→target word map
    "cordless": "kabellos",
    "drill": "Bohrmaschine"
  }
}

Response

A successful request returns HTTP 200 with a JSON body containing the localized listing fields, gate results for all six quality checks, a violations array (empty when all gates pass), and a top-level pass boolean. A pass: false result means at least one gate failed — check violations for the exact field and reason. Common causes: title exceeds Amazon Germany's character limit, a banned keyword appeared in the German copy, a model number or unit was altered during translation (preservation gate), or the back-translation divergence score exceeded the threshold.

{
  "localized": {
    "title": "Kabellose Bohrmaschine AB-1200 mit 8,5-kg-Akku und 2-m-Kabel",
    "description": "Kabellose Bohrmaschine AB-1200 mit einem 8,5-kg-Akku und einem 2-m-Kabel.",
    "brand": "Bosch",
    "material": "Metall",
    "size": "M",
    "color": "blau",
    "quantity": 1
  },
  "gates": {
    "titleLength":        { "pass": true, "length": 67, "limit": 200 },
    "bannedWords":        { "pass": true },
    "requiredAttributes": { "pass": true },
    "preservation":       { "pass": true },
    "glossary":           { "pass": true },
    "backTranslation":    { "pass": true, "score": 0.12, "threshold": 0.25 }
  },
  "violations": [],
  "pass": true
}

Understanding violations

When a gate fails, the response contains pass: false and a violations array. Each violation includes a message explaining what failed and a hint telling you exactly what to fix. Here is a real failing response for a listing that contains a banned word and a missing required attribute:

{
  "localized": {
    "title": "Kabellose Bohrmaschine AB-1200 garantiert top",
    "description": "Kabellose Bohrmaschine AB-1200 mit ein Akku und ein Kabel.",
    "brand": "Bosch",
    "material": "Metall",
    "color": "blau",
    "quantity": 1
  },
  "gates": {
    "titleLength":        { "pass": true, "violations": [] },
    "bannedWords":        { "pass": false, "violations": [
      {
        "type": "banned_word",
        "word": "garantiert",
        "message": "The term 'garantiert' is not permitted in this marketplace.",
        "hint": "Remove this term."
      }
    ]},
    "requiredAttributes": { "pass": false, "violations": [
      {
        "type": "missing_attribute",
        "attribute": "size",
        "message": "Required attribute 'size' is absent or empty.",
        "hint": "Add the missing attribute."
      }
    ]},
    "preservation":       { "pass": true, "violations": [] },
    "glossary":           { "pass": true, "violations": [] },
    "backTranslation":    { "pass": true, "score": 0.18, "threshold": 0.25, "enforced": true }
  },
  "violations": [
    {
      "gate": "bannedWords",
      "type": "banned_word",
      "word": "garantiert",
      "message": "The term 'garantiert' is not permitted in this marketplace.",
      "hint": "Remove this term."
    },
    {
      "gate": "requiredAttributes",
      "type": "missing_attribute",
      "attribute": "size",
      "message": "Required attribute 'size' is absent or empty.",
      "hint": "Add the missing attribute."
    }
  ],
  "pass": false
}

Read each violation's message to understand what rule was broken, then follow its hint to fix it. The gate field tells you which quality check raised the violation. After fixing all violations, re-submit until pass: true.

X-Quota-Limit: 100
X-Quota-Used: 12
X-Quota-Remaining: 88

Quality gates

Every response runs six deterministic checks. The same input always returns the same result — no random variation.

• titleLength — Amazon Germany title character limit (200 chars). A suppressed listing often traces back to an overlong title.
• bannedWords — Detects restricted German terms such as garantiert, bestseller, and antibakteriell that violate Amazon DE policy.
• requiredAttributes — Verifies brand, material, size, color, and quantity are present in the localized output.
• preservation — Confirms that model numbers, numeric values, and measurement units (e.g. AB-1200, 8.5 kg, 2 m) survived translation unchanged.
• glossary — Checks that every term in glossary.preserve appears verbatim in the localized output.
• backTranslation — Translates the German output back to English and measures lexical divergence. A high score means the localized text drifted semantically from the source.

Import into Postman

Download the ready-made Postman collection to explore both endpoints without writing any code. Open Postman, choose Import → Link, and paste the URL below — or click the button to download the file directly.

Error reference

Every non-2xx response from POST /localize includes three fields: error (human-readable message), code (stable machine-readable identifier), and docs (URL to this section). Switch on code in your client — the exact wording of error may change, but code values are frozen.

Next steps

Subscribe to a plan on RapidAPI and paste your key into the curl command above. The OpenAPI spec documents every field and error code. The blog covers common Amazon DE localization problems — suppressed listings, banned keywords, and model-number preservation — with worked examples.

Subscribe on RapidAPI See plans and pricing OpenAPI spec Read the blog