curl --request GET \
  --url https://{host}/v1/specifications/{id} \
  --header 'Authorization: Bearer <token>'

const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://{host}/v1/specifications/{id}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://{host}/v1/specifications/{id}",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

import requests

url = "https://{host}/v1/specifications/{id}"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.text)

{
  "data": {
    "type": "specifications",
    "id": "CASE_MATERIAL",
    "attributes": {
      "label": "Case material",
      "category": "CASE",
      "required": false,
      "filter": "attributes.case_material",
      "values": [
        {
          "value": "STEEL",
          "label": "Steel"
        },
        {
          "value": "GOLD_STEEL",
          "label": "Gold/Steel"
        },
        {
          "value": "TITANIUM",
          "label": "Titanium"
        },
        {
          "value": "CERAMIC",
          "label": "Ceramic"
        }
      ]
    },
    "links": {
      "self": "https://api.wristler.eu/v1/specifications/CASE_MATERIAL"
    }
  }
}

{
  "errors": [
    {
      "status": "404",
      "code": "watch_reserved",
      "title": "Not Found",
      "detail": "<string>",
      "meta": {},
      "source": {
        "pointer": "/data/attributes/reference",
        "parameter": "<string>"
      }
    }
  ],
  "jsonapi": {
    "version": "1.0"
  }
}

{
  "errors": [
    {
      "status": "404",
      "code": "watch_reserved",
      "title": "Not Found",
      "detail": "<string>",
      "meta": {},
      "source": {
        "pointer": "/data/attributes/reference",
        "parameter": "<string>"
      }
    }
  ],
  "jsonapi": {
    "version": "1.0"
  }
}