Every GAEB format.
One API.

cURL Python PHP .NET Java

curl https://www.gaeb-box.de/api/conversion/gaeb/ava \
  -H "Authorization: Bearer $GAEBBOX_KEY" \
  -F "file={{ $filename }}"

import requests

r = requests.post(
    "https://www.gaeb-box.de/api/conversion/gaeb/ava",
    headers={"Authorization": f"Bearer {GAEBBOX_KEY}"},
    files={"file": open("tender.x83", "rb")},
)
print(r.json())

$client = new \GuzzleHttp\Client();
$response = $client->post('https://www.gaeb-box.de/api/conversion/gaeb/ava', [
    'headers' => ['Authorization' => "Bearer {$gaebboxKey}"],
    'multipart' => [[
        'name' => 'file',
        'contents' => fopen('tender.x83', 'r'),
    ]],
]);
echo $response->getBody();

using var client = new HttpClient();
client.DefaultRequestHeaders.Authorization =
    new AuthenticationHeaderValue("Bearer", gaebboxKey);

using var form = new MultipartFormDataContent();
form.Add(new StreamContent(File.OpenRead("tender.x83")), "file", "tender.x83");

var response = await client.PostAsync(
    "https://www.gaeb-box.de/api/conversion/gaeb/ava", form);
var json = await response.Content.ReadAsStringAsync();

OkHttpClient client = new OkHttpClient();
RequestBody body = new MultipartBody.Builder()
    .setType(MultipartBody.FORM)
    .addFormDataPart("file", "tender.x83",
        RequestBody.create(new File("tender.x83"),
            MediaType.parse("application/octet-stream")))
    .build();

Request request = new Request.Builder()
    .url("https://www.gaeb-box.de/api/conversion/gaeb/ava")
    .header("Authorization", "Bearer " + gaebboxKey)
    .post(body)
    .build();

try (Response response = client.newCall(request).execute()) {
    System.out.println(response.body().string());
}

200 OK

{
  "name": "…",
  "currencyShort": "EUR",
  "elements": [{
    "oz": "01.02.0010",
    "shortText": "Baugrube ausheben",
    "quantity": 420.5,
    "unit": "m3"
  }]
}