curl --request POST \
  --url https://api.sequence.app/rpc/API/LinkWallet \
  --header 'Content-Type: application/json' \
  --header 'X-Access-Key: <api-key>' \
  --data '
{
  "signatureChainId": "137",
  "linkedWalletType": "MetaMask",
  "parentWalletAddress": "0xb33018E5C4f5A168f5560D9C05597508dA8a4E91",
  "parentWalletMessage": "child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6",
  "parentWalletSignature": "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",
  "linkedWalletAddress": "0x4f8A351143A0aAec055873959b8Cb705c00a37F6",
  "linkedWalletMessage": "Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91",
  "linkedWalletSignature": "0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c"
}
'

import requests

url = "https://api.sequence.app/rpc/API/LinkWallet"

payload = {
    "signatureChainId": "137",
    "linkedWalletType": "MetaMask",
    "parentWalletAddress": "0xb33018E5C4f5A168f5560D9C05597508dA8a4E91",
    "parentWalletMessage": "child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6",
    "parentWalletSignature": "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",
    "linkedWalletAddress": "0x4f8A351143A0aAec055873959b8Cb705c00a37F6",
    "linkedWalletMessage": "Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91",
    "linkedWalletSignature": "0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c"
}
headers = {
    "X-Access-Key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-Access-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    signatureChainId: '137',
    linkedWalletType: 'MetaMask',
    parentWalletAddress: '0xb33018E5C4f5A168f5560D9C05597508dA8a4E91',
    parentWalletMessage: 'child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6',
    parentWalletSignature: '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',
    linkedWalletAddress: '0x4f8A351143A0aAec055873959b8Cb705c00a37F6',
    linkedWalletMessage: 'Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91',
    linkedWalletSignature: '0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c'
  })
};

fetch('https://api.sequence.app/rpc/API/LinkWallet', 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://api.sequence.app/rpc/API/LinkWallet",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'signatureChainId' => '137',
    'linkedWalletType' => 'MetaMask',
    'parentWalletAddress' => '0xb33018E5C4f5A168f5560D9C05597508dA8a4E91',
    'parentWalletMessage' => 'child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6',
    'parentWalletSignature' => '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',
    'linkedWalletAddress' => '0x4f8A351143A0aAec055873959b8Cb705c00a37F6',
    'linkedWalletMessage' => 'Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91',
    'linkedWalletSignature' => '0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-Access-Key: <api-key>"
  ],
]);

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

curl_close($curl);

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

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.sequence.app/rpc/API/LinkWallet"

	payload := strings.NewReader("{\n  \"signatureChainId\": \"137\",\n  \"linkedWalletType\": \"MetaMask\",\n  \"parentWalletAddress\": \"0xb33018E5C4f5A168f5560D9C05597508dA8a4E91\",\n  \"parentWalletMessage\": \"child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6\",\n  \"parentWalletSignature\": \"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\",\n  \"linkedWalletAddress\": \"0x4f8A351143A0aAec055873959b8Cb705c00a37F6\",\n  \"linkedWalletMessage\": \"Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91\",\n  \"linkedWalletSignature\": \"0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-Access-Key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.sequence.app/rpc/API/LinkWallet")
  .header("X-Access-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"signatureChainId\": \"137\",\n  \"linkedWalletType\": \"MetaMask\",\n  \"parentWalletAddress\": \"0xb33018E5C4f5A168f5560D9C05597508dA8a4E91\",\n  \"parentWalletMessage\": \"child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6\",\n  \"parentWalletSignature\": \"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\",\n  \"linkedWalletAddress\": \"0x4f8A351143A0aAec055873959b8Cb705c00a37F6\",\n  \"linkedWalletMessage\": \"Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91\",\n  \"linkedWalletSignature\": \"0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.sequence.app/rpc/API/LinkWallet")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-Access-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"signatureChainId\": \"137\",\n  \"linkedWalletType\": \"MetaMask\",\n  \"parentWalletAddress\": \"0xb33018E5C4f5A168f5560D9C05597508dA8a4E91\",\n  \"parentWalletMessage\": \"child wallet with address 0x4f8A351143A0aAec055873959b8Cb705c00a37F6\",\n  \"parentWalletSignature\": \"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\",\n  \"linkedWalletAddress\": \"0x4f8A351143A0aAec055873959b8Cb705c00a37F6\",\n  \"linkedWalletMessage\": \"Link to parent wallet with address 0xb33018E5C4f5A168f5560D9C05597508dA8a4E91\",\n  \"linkedWalletSignature\": \"0x0d31791e6aefbd01590f846e93a7740988a6d5ffc50a59ee0941747c2740242a3ec105fddf66a8b39b49db5d13de9d68a36c5fd7e1e83da1e01657c9996d87181c\"\n}"

response = http.request(request)
puts response.read_body

{
  "status": true
}

{
  "error": "WebrpcEndpoint",
  "code": 0,
  "msg": "endpoint error",
  "status": 400,
  "cause": "<string>"
}

{
  "error": "WebrpcBadResponse",
  "code": -5,
  "msg": "bad response",
  "status": 500,
  "cause": "<string>"
}