From 34654af717784f20f69a089cf7b5a0a376749eb6 Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Tue, 24 Mar 2026 02:03:44 +0530
Subject: [PATCH 1/9] feat: add Vonage Messages API adapter

---
 .../Messaging/Adapter/SMS/VonageMessages.php  | 88 +++++++++++++++++++
 .../Messaging/Adapter/VonageMessagesBase.php  | 45 ++++++++++
 .../Adapter/SMS/VonageMessagesTest.php        | 39 ++++++++
 3 files changed, 172 insertions(+)
 create mode 100644 src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
 create mode 100644 src/Utopia/Messaging/Adapter/VonageMessagesBase.php
 create mode 100644 tests/Messaging/Adapter/SMS/VonageMessagesTest.php

diff --git a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
new file mode 100644
index 00000000..eed43878
--- /dev/null
+++ b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
@@ -0,0 +1,88 @@
+<?php
+
+namespace Utopia\Messaging\Adapter\SMS;
+
+use Utopia\Messaging\Adapter\SMS as SMSAdapter;
+use Utopia\Messaging\Adapter\VonageMessagesBase;
+use Utopia\Messaging\Messages\SMS as SMSMessage;
+use Utopia\Messaging\Response;
+
+/**
+ * Vonage Messages API SMS Adapter.
+ *
+ * Uses the newer Vonage Messages API (V1) instead of the older SMS API.
+ * The Messages API is cheaper and supports multiple message types.
+ *
+ * Reference: https://developer.vonage.com/en/api/messages
+ */
+class VonageMessages extends SMSAdapter
+{
+    use VonageMessagesBase;
+
+    protected const NAME = 'Vonage Messages';
+
+    /**
+     * @param  string  $apiKey Vonage API Key
+     * @param  string  $apiSecret Vonage API Secret
+     */
+    public function __construct(
+        /** @phpstan-ignore property.onlyWritten */
+        private string $apiKey,
+        /** @phpstan-ignore property.onlyWritten */
+        private string $apiSecret,
+        private ?string $from = null
+    ) {
+    }
+
+    public function getName(): string
+    {
+        return static::NAME;
+    }
+
+    public function getMaxMessagesPerRequest(): int
+    {
+        return 1;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function process(SMSMessage $message): array
+    {
+        $to = \ltrim($message->getTo()[0], '+');
+        $from = $this->from ?? $message->getFrom();
+
+        $response = new Response($this->getType());
+
+        $result = $this->request(
+            method: 'POST',
+            url: $this->getApiEndpoint(),
+            headers: $this->getRequestHeaders(),
+            body: [
+                'message_type' => 'text',
+                'to' => $to,
+                'from' => $from,
+                'text' => $message->getContent(),
+                'channel' => 'sms',
+            ],
+        );
+
+        if ($result['statusCode'] === 202) {
+            $response->setDeliveredTo(1);
+            $response->addResult($message->getTo()[0]);
+        } else {
+            $errorMessage = 'Unknown error';
+            if (isset($result['response']['detail'])) {
+                $errorMessage = $result['response']['detail'];
+            } elseif (isset($result['response']['title'])) {
+                $errorMessage = $result['response']['title'];
+            } elseif (!empty($result['error'])) {
+                $errorMessage = $result['error'];
+            }
+
+            $response->addResult($message->getTo()[0], $errorMessage);
+        }
+
+        return $response->toArray();
+    }
+}
diff --git a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
new file mode 100644
index 00000000..577a2a44
--- /dev/null
+++ b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
@@ -0,0 +1,45 @@
+<?php
+
+namespace Utopia\Messaging\Adapter;
+
+/**
+ * Trait for Vonage Messages API adapters.
+ *
+ * Provides common functionality for adapters using the Vonage Messages API (V1).
+ * This trait can be used by different message type adapters (SMS, Chat, etc.).
+ *
+ * Required properties (from extending class):
+ * - $apiKey: string
+ * - $apiSecret: string
+ *
+ * Reference: https://developer.vonage.com/en/api/messages
+ */
+trait VonageMessagesBase
+{
+    /**
+     * Get the API endpoint for the Vonage Messages API.
+     */
+    protected function getApiEndpoint(): string
+    {
+        return 'https://api.nexmo.com/v1/messages';
+    }
+
+    protected function getAuthorizationHeader(): string
+    {
+        return 'Basic ' . \base64_encode("{$this->apiKey}:{$this->apiSecret}");
+    }
+
+    /**
+     * Build the request headers for the Messages API.
+     *
+     * @return array<string>
+     */
+    protected function getRequestHeaders(): array
+    {
+        return [
+            "Authorization: {$this->getAuthorizationHeader()}",
+            'Content-Type: application/json',
+            'Accept: application/json',
+        ];
+    }
+}
diff --git a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
new file mode 100644
index 00000000..6eeaca94
--- /dev/null
+++ b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
@@ -0,0 +1,39 @@
+<?php
+
+namespace Utopia\Tests\Adapter\SMS;
+
+use Utopia\Messaging\Adapter\SMS\VonageMessages;
+use Utopia\Messaging\Messages\SMS;
+use Utopia\Tests\Adapter\Base;
+
+class VonageMessagesTest extends Base
+{
+    /**
+     * @throws \Exception
+     */
+    public function testSendSMS(): void
+    {
+        $apiKey = \getenv('VONAGE_API_KEY');
+        $apiSecret = \getenv('VONAGE_API_SECRET');
+
+        if (!$apiKey || !$apiSecret) {
+            $this->markTestSkipped('Vonage Messages credentials are not available.');
+        }
+
+        $sender = new VonageMessages(
+            apiKey: $apiKey,
+            apiSecret: $apiSecret,
+            from: \getenv('VONAGE_FROM') ?: 'Vonage',
+        );
+
+        $message = new SMS(
+            to: [\getenv('VONAGE_TO')],
+            content: 'Test Content',
+            from: \getenv('VONAGE_FROM')
+        );
+
+        $response = $sender->send($message);
+
+        $this->assertResponse($response);
+    }
+}

From 5f92f6452f7b541739f7db5f62faa6c457febb8b Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Wed, 1 Apr 2026 13:55:24 +0530
Subject: [PATCH 2/9] fix: address code review feedback (Vonage domain, from
 formatting, test coverage)

---
 .../Messaging/Adapter/SMS/VonageMessages.php  |  9 ++++-
 .../Messaging/Adapter/VonageMessagesBase.php  |  5 ++-
 .../Adapter/SMS/VonageMessagesTest.php        | 37 +++++++++++++++++--
 3 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
index eed43878..286a9f1d 100644
--- a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
+++ b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
@@ -26,9 +26,7 @@ class VonageMessages extends SMSAdapter
      * @param  string  $apiSecret Vonage API Secret
      */
     public function __construct(
-        /** @phpstan-ignore property.onlyWritten */
         private string $apiKey,
-        /** @phpstan-ignore property.onlyWritten */
         private string $apiSecret,
         private ?string $from = null
     ) {
@@ -54,6 +52,13 @@ protected function process(SMSMessage $message): array
 
         $response = new Response($this->getType());
 
+        if (empty($from)) {
+            $response->addResult($message->getTo()[0], 'The "from" field is required for the Vonage Messages API.');
+            return $response->toArray();
+        }
+
+        $from = \ltrim($from, '+');
+
         $result = $this->request(
             method: 'POST',
             url: $this->getApiEndpoint(),
diff --git a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
index 577a2a44..09ce5e2f 100644
--- a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
+++ b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
@@ -21,9 +21,12 @@ trait VonageMessagesBase
      */
     protected function getApiEndpoint(): string
     {
-        return 'https://api.nexmo.com/v1/messages';
+        return 'https://api.vonage.com/v1/messages';
     }
 
+    /**
+     * @todo Implement JWT authentication for non-SMS channels
+     */
     protected function getAuthorizationHeader(): string
     {
         return 'Basic ' . \base64_encode("{$this->apiKey}:{$this->apiSecret}");
diff --git a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
index 6eeaca94..25890d4b 100644
--- a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
+++ b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
@@ -15,9 +15,10 @@ public function testSendSMS(): void
     {
         $apiKey = \getenv('VONAGE_API_KEY');
         $apiSecret = \getenv('VONAGE_API_SECRET');
+        $to = \getenv('VONAGE_TO');
 
-        if (!$apiKey || !$apiSecret) {
-            $this->markTestSkipped('Vonage Messages credentials are not available.');
+        if (!$apiKey || !$apiSecret || !$to) {
+            $this->markTestSkipped('Vonage Messages credentials or recipient are not available.');
         }
 
         $sender = new VonageMessages(
@@ -27,7 +28,7 @@ public function testSendSMS(): void
         );
 
         $message = new SMS(
-            to: [\getenv('VONAGE_TO')],
+            to: [$to],
             content: 'Test Content',
             from: \getenv('VONAGE_FROM')
         );
@@ -36,4 +37,34 @@ public function testSendSMS(): void
 
         $this->assertResponse($response);
     }
+
+    /**
+     * @throws \Exception
+     */
+    public function testSendSMSWithFallbackFrom(): void
+    {
+        $apiKey = \getenv('VONAGE_API_KEY');
+        $apiSecret = \getenv('VONAGE_API_SECRET');
+        $to = \getenv('VONAGE_TO');
+        $from = \getenv('VONAGE_FROM');
+
+        if (!$apiKey || !$apiSecret || !$to || !$from) {
+            $this->markTestSkipped('Vonage Messages credentials or sender/recipient are not available.');
+        }
+
+        $sender = new VonageMessages(
+            apiKey: $apiKey,
+            apiSecret: $apiSecret,
+        );
+
+        $message = new SMS(
+            to: [$to],
+            content: 'Test Content',
+            from: $from
+        );
+
+        $response = $sender->send($message);
+
+        $this->assertResponse($response);
+    }
 }

From 3b8e2c413c402ac5aa6dcafb5c2850e4cf380298 Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Wed, 1 Apr 2026 14:07:17 +0530
Subject: [PATCH 3/9] test: refine type safety and isolate fallback logic in
 Vonage tests

---
 tests/Messaging/Adapter/SMS/VonageMessagesTest.php | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
index 25890d4b..b26a758a 100644
--- a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
+++ b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
@@ -30,7 +30,6 @@ public function testSendSMS(): void
         $message = new SMS(
             to: [$to],
             content: 'Test Content',
-            from: \getenv('VONAGE_FROM')
         );
 
         $response = $sender->send($message);
@@ -46,7 +45,7 @@ public function testSendSMSWithFallbackFrom(): void
         $apiKey = \getenv('VONAGE_API_KEY');
         $apiSecret = \getenv('VONAGE_API_SECRET');
         $to = \getenv('VONAGE_TO');
-        $from = \getenv('VONAGE_FROM');
+        $from = \getenv('VONAGE_FROM') ?: null;
 
         if (!$apiKey || !$apiSecret || !$to || !$from) {
             $this->markTestSkipped('Vonage Messages credentials or sender/recipient are not available.');
@@ -60,7 +59,7 @@ public function testSendSMSWithFallbackFrom(): void
         $message = new SMS(
             to: [$to],
             content: 'Test Content',
-            from: $from
+            from: $from,
         );
 
         $response = $sender->send($message);

From c1ef16ed854cc3de8e9d3ba3f41f0835ad24868e Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Wed, 1 Apr 2026 14:12:52 +0530
Subject: [PATCH 4/9] docs: improve docstring coverage for Vonage methods to
 meet CI threshold

---
 src/Utopia/Messaging/Adapter/SMS/VonageMessages.php | 6 ++++++
 src/Utopia/Messaging/Adapter/VonageMessagesBase.php | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
index 286a9f1d..a316513e 100644
--- a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
+++ b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
@@ -32,11 +32,17 @@ public function __construct(
     ) {
     }
 
+    /**
+     * Get adapter name.
+     */
     public function getName(): string
     {
         return static::NAME;
     }
 
+    /**
+     * Get max messages per request.
+     */
     public function getMaxMessagesPerRequest(): int
     {
         return 1;
diff --git a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
index 09ce5e2f..22659fa0 100644
--- a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
+++ b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
@@ -25,6 +25,8 @@ protected function getApiEndpoint(): string
     }
 
     /**
+     * Get the authorization header value for the API request.
+     *
      * @todo Implement JWT authentication for non-SMS channels
      */
     protected function getAuthorizationHeader(): string

From 6fa3699a5f0bcb3f46f8a3d76dd7c0f55f0de557 Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Wed, 1 Apr 2026 14:37:22 +0530
Subject: [PATCH 5/9] fix: move from field trimming before empty guard

---
 src/Utopia/Messaging/Adapter/SMS/VonageMessages.php | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
index a316513e..396180ef 100644
--- a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
+++ b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
@@ -55,6 +55,7 @@ protected function process(SMSMessage $message): array
     {
         $to = \ltrim($message->getTo()[0], '+');
         $from = $this->from ?? $message->getFrom();
+        $from = $from !== null ? \ltrim($from, '+') : null;
 
         $response = new Response($this->getType());
 
@@ -63,8 +64,6 @@ protected function process(SMSMessage $message): array
             return $response->toArray();
         }
 
-        $from = \ltrim($from, '+');
-
         $result = $this->request(
             method: 'POST',
             url: $this->getApiEndpoint(),

From 449c941f28aa47f1d478d22ef13d080147c04b78 Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Fri, 10 Apr 2026 21:18:27 +0530
Subject: [PATCH 6/9] docs: add Vonage Messages to supported SMS adapters list

---
 README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/README.md b/README.md
index ac0deabf..1f059586 100644
--- a/README.md
+++ b/README.md
@@ -110,6 +110,7 @@ $messaging->send($message);
 - [x] [Textmagic](https://www.textmagic.com/)
 - [x] [Msg91](https://msg91.com/)
 - [x] [Vonage](https://www.vonage.com/)
+- [x] [Vonage Messages](https://www.vonage.com/)
 - [x] [Plivo](https://www.plivo.com/)
 - [x] [Infobip](https://www.infobip.com/)
 - [x] [Clickatell](https://www.clickatell.com/)

From 4bcbabd501fcd7a71b41e50e6dedd66e83c2957b Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Fri, 10 Apr 2026 21:21:17 +0530
Subject: [PATCH 7/9] fix: address review feedback (remove base class/trait for
 Vonage)

---
 .../Messaging/Adapter/SMS/VonageMessages.php  | 36 +++++++++++--
 .../Messaging/Adapter/VonageMessagesBase.php  | 50 -------------------
 2 files changed, 33 insertions(+), 53 deletions(-)
 delete mode 100644 src/Utopia/Messaging/Adapter/VonageMessagesBase.php

diff --git a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
index 396180ef..c8e34223 100644
--- a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
+++ b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
@@ -3,7 +3,6 @@
 namespace Utopia\Messaging\Adapter\SMS;
 
 use Utopia\Messaging\Adapter\SMS as SMSAdapter;
-use Utopia\Messaging\Adapter\VonageMessagesBase;
 use Utopia\Messaging\Messages\SMS as SMSMessage;
 use Utopia\Messaging\Response;
 
@@ -17,8 +16,6 @@
  */
 class VonageMessages extends SMSAdapter
 {
-    use VonageMessagesBase;
-
     protected const NAME = 'Vonage Messages';
 
     /**
@@ -32,6 +29,39 @@ public function __construct(
     ) {
     }
 
+    /**
+     * Get the API endpoint for the Vonage Messages API.
+     */
+    protected function getApiEndpoint(): string
+    {
+        return 'https://api.vonage.com/v1/messages';
+    }
+
+    /**
+     * Get the authorization header value for the API request.
+     *
+     * @todo Implement JWT authentication for non-SMS channels
+     */
+    protected function getAuthorizationHeader(): string
+    {
+        return 'Basic ' . \base64_encode("{$this->apiKey}:{$this->apiSecret}");
+    }
+
+    /**
+     * Build the request headers for the Messages API.
+     *
+     * @return array<string>
+     */
+    protected function getRequestHeaders(): array
+    {
+        return [
+            "Authorization: {$this->getAuthorizationHeader()}",
+            'Content-Type: application/json',
+            'Accept: application/json',
+            'User-Agent: Utopia Messaging',
+        ];
+    }
+
     /**
      * Get adapter name.
      */
diff --git a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php b/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
deleted file mode 100644
index 22659fa0..00000000
--- a/src/Utopia/Messaging/Adapter/VonageMessagesBase.php
+++ /dev/null
@@ -1,50 +0,0 @@
-<?php
-
-namespace Utopia\Messaging\Adapter;
-
-/**
- * Trait for Vonage Messages API adapters.
- *
- * Provides common functionality for adapters using the Vonage Messages API (V1).
- * This trait can be used by different message type adapters (SMS, Chat, etc.).
- *
- * Required properties (from extending class):
- * - $apiKey: string
- * - $apiSecret: string
- *
- * Reference: https://developer.vonage.com/en/api/messages
- */
-trait VonageMessagesBase
-{
-    /**
-     * Get the API endpoint for the Vonage Messages API.
-     */
-    protected function getApiEndpoint(): string
-    {
-        return 'https://api.vonage.com/v1/messages';
-    }
-
-    /**
-     * Get the authorization header value for the API request.
-     *
-     * @todo Implement JWT authentication for non-SMS channels
-     */
-    protected function getAuthorizationHeader(): string
-    {
-        return 'Basic ' . \base64_encode("{$this->apiKey}:{$this->apiSecret}");
-    }
-
-    /**
-     * Build the request headers for the Messages API.
-     *
-     * @return array<string>
-     */
-    protected function getRequestHeaders(): array
-    {
-        return [
-            "Authorization: {$this->getAuthorizationHeader()}",
-            'Content-Type: application/json',
-            'Accept: application/json',
-        ];
-    }
-}

From a1d89cef7b073209a04ad3498a047427a542e619 Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Fri, 10 Apr 2026 21:22:42 +0530
Subject: [PATCH 8/9] revert: remove documentation changes for Vonage Messages

---
 README.md | 1 -
 1 file changed, 1 deletion(-)

diff --git a/README.md b/README.md
index 1f059586..ac0deabf 100644
--- a/README.md
+++ b/README.md
@@ -110,7 +110,6 @@ $messaging->send($message);
 - [x] [Textmagic](https://www.textmagic.com/)
 - [x] [Msg91](https://msg91.com/)
 - [x] [Vonage](https://www.vonage.com/)
-- [x] [Vonage Messages](https://www.vonage.com/)
 - [x] [Plivo](https://www.plivo.com/)
 - [x] [Infobip](https://www.infobip.com/)
 - [x] [Clickatell](https://www.clickatell.com/)

From 31fa7f1e31d2d6c521ed6f426776b001c2496818 Mon Sep 17 00:00:00 2001
From: bhardwajparth51 <196071556+bhardwajparth51@users.noreply.github.com>
Date: Fri, 10 Apr 2026 21:38:58 +0530
Subject: [PATCH 9/9] fix: address review feedback and harden error handling

---
 .../Messaging/Adapter/SMS/VonageMessages.php  | 58 ++++++-------------
 .../Adapter/SMS/VonageMessagesTest.php        |  8 +--
 2 files changed, 21 insertions(+), 45 deletions(-)

diff --git a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
index c8e34223..5dc2cdd1 100644
--- a/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
+++ b/src/Utopia/Messaging/Adapter/SMS/VonageMessages.php
@@ -6,22 +6,14 @@
 use Utopia\Messaging\Messages\SMS as SMSMessage;
 use Utopia\Messaging\Response;
 
-/**
- * Vonage Messages API SMS Adapter.
- *
- * Uses the newer Vonage Messages API (V1) instead of the older SMS API.
- * The Messages API is cheaper and supports multiple message types.
- *
- * Reference: https://developer.vonage.com/en/api/messages
- */
+// Vonage Messages API SMS Adapter.
+// This adapter uses the modern Vonage Messages API (V1) which is more cost-effective
+// and versatile than the legacy SMS API.
+// https://developer.vonage.com/en/api/messages
 class VonageMessages extends SMSAdapter
 {
     protected const NAME = 'Vonage Messages';
 
-    /**
-     * @param  string  $apiKey Vonage API Key
-     * @param  string  $apiSecret Vonage API Secret
-     */
     public function __construct(
         private string $apiKey,
         private string $apiSecret,
@@ -29,29 +21,19 @@ public function __construct(
     ) {
     }
 
-    /**
-     * Get the API endpoint for the Vonage Messages API.
-     */
+    // Vonage Messages API endpoint.
     protected function getApiEndpoint(): string
     {
         return 'https://api.vonage.com/v1/messages';
     }
 
-    /**
-     * Get the authorization header value for the API request.
-     *
-     * @todo Implement JWT authentication for non-SMS channels
-     */
+    // Generates the Basic Authorization header.
     protected function getAuthorizationHeader(): string
     {
         return 'Basic ' . \base64_encode("{$this->apiKey}:{$this->apiSecret}");
     }
 
-    /**
-     * Build the request headers for the Messages API.
-     *
-     * @return array<string>
-     */
+    // Sets common headers for the API request.
     protected function getRequestHeaders(): array
     {
         return [
@@ -62,25 +44,18 @@ protected function getRequestHeaders(): array
         ];
     }
 
-    /**
-     * Get adapter name.
-     */
+    // Get adapter name.
     public function getName(): string
     {
         return static::NAME;
     }
 
-    /**
-     * Get max messages per request.
-     */
+    // Get max messages per request.
     public function getMaxMessagesPerRequest(): int
     {
         return 1;
     }
 
-    /**
-     * {@inheritdoc}
-     */
     protected function process(SMSMessage $message): array
     {
         $to = \ltrim($message->getTo()[0], '+');
@@ -111,13 +86,18 @@ protected function process(SMSMessage $message): array
             $response->setDeliveredTo(1);
             $response->addResult($message->getTo()[0]);
         } else {
-            $errorMessage = 'Unknown error';
-            if (isset($result['response']['detail'])) {
-                $errorMessage = $result['response']['detail'];
-            } elseif (isset($result['response']['title'])) {
-                $errorMessage = $result['response']['title'];
+            $errorMessage = "Error {$result['statusCode']}";
+
+            if (\is_array($result['response'])) {
+                if (isset($result['response']['detail'])) {
+                    $errorMessage = $result['response']['detail'];
+                } elseif (isset($result['response']['title'])) {
+                    $errorMessage = $result['response']['title'];
+                }
             } elseif (!empty($result['error'])) {
                 $errorMessage = $result['error'];
+            } elseif (\is_string($result['response']) && !empty($result['response'])) {
+                $errorMessage = "Error {$result['statusCode']}: " . \mb_strimwidth(\strip_tags($result['response']), 0, 100, '...');
             }
 
             $response->addResult($message->getTo()[0], $errorMessage);
diff --git a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
index b26a758a..6711ed2f 100644
--- a/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
+++ b/tests/Messaging/Adapter/SMS/VonageMessagesTest.php
@@ -8,9 +8,7 @@
 
 class VonageMessagesTest extends Base
 {
-    /**
-     * @throws \Exception
-     */
+    // Tests sending an SMS with the 'from' number set directly in the adapter.
     public function testSendSMS(): void
     {
         $apiKey = \getenv('VONAGE_API_KEY');
@@ -37,9 +35,7 @@ public function testSendSMS(): void
         $this->assertResponse($response);
     }
 
-    /**
-     * @throws \Exception
-     */
+    // Tests sending an SMS where the 'from' number is provided by the message object.
     public function testSendSMSWithFallbackFrom(): void
     {
         $apiKey = \getenv('VONAGE_API_KEY');