Getting Started with Contactually API v2 - PHP

01_set_up_client.php

use GuzzleHttp\Client;

$client = new Client([
    'base_uri' => 'https://api.contactually.com',
    'headers'  => [
        'Accept': 'application/json',
        'Authorization': 'Bearer AUTH_TOKEN_HERE'
    ],
]);

02_get_current_user.php

$response = $client->get('/v2/me');

echo $response->getBody();

03_create_and_bucket_contact.php

contactAttributes = [
  'first_name' => 'Jonathan',
  'last_name' => 'Bender',
  'email' => 'jbender@contactually.com'
];

# Create the contact
$response = $client->request('POST', '/v2/contacts', [
  'json' => [ 'data' => contactAttributes ]
]);

$contact = $response->getBody()['data'];

# Get the available buckets
$bucketsResponse = $client->get('/v2/buckets');
$buckets = $bucketsResponse->getBody()['data'];

# Add the bucket to the created contact
newBuckets = [[ 'id' => $buckets[0]['id'] ]];

$client->request('POST', "/v2/contacts/{$contact['id']}/buckets", [
  'json' => [ 'data' => $newBuckets ]
]);

There is a problem with your code, the : should be => for key pair assignments

use GuzzleHttp\Client;

$client = new Client([
'base_uri' => 'https://api.contactually.com',
'headers' => [
'Accept': 'application/json',
'Authorization': 'Bearer AUTH_TOKEN_HERE'
],
]);

should be:

use GuzzleHttp\Client;

$client = new Client([
'base_uri' => 'https://api.contactually.com',
'headers' => [
'Accept' => 'application/json',
'Authorization' => 'Bearer AUTH_TOKEN_HERE'
],
]);

There are also 2 variable which are declared without the $ syntax:

$contactAttributes
$newBuckets