diff --git a/src/Anthropic/Platform/Anthropic.php b/src/Anthropic/Platform/Anthropic.php
index 891823b6..b2054003 100644
--- a/src/Anthropic/Platform/Anthropic.php
+++ b/src/Anthropic/Platform/Anthropic.php
@@ -31,7 +31,6 @@ public function request(array $body): iterable
         $response = $this->httpClient->request('POST', 'https://api.anthropic.com/v1/messages', [
             'headers' => [
                 'x-api-key' => $this->apiKey,
-                'Content-Type' => 'application/json',
                 'anthropic-version' => '2023-06-01',
             ],
             'json' => $body,
diff --git a/src/OpenAI/Platform/Azure.php b/src/OpenAI/Platform/Azure.php
index 3b0a5f78..84d3da45 100644
--- a/src/OpenAI/Platform/Azure.php
+++ b/src/OpenAI/Platform/Azure.php
@@ -30,7 +30,6 @@ protected function rawRequest(string $endpoint, array $body): ResponseInterface
         return $this->httpClient->request('POST', $url, [
             'headers' => [
                 'api-key' => $this->apiKey,
-                'Content-Type' => 'application/json',
             ],
             'query' => ['api-version' => $this->apiVersion],
             'json' => $body,
diff --git a/src/OpenAI/Platform/OpenAI.php b/src/OpenAI/Platform/OpenAI.php
index b3d4bfde..8dfac1b5 100644
--- a/src/OpenAI/Platform/OpenAI.php
+++ b/src/OpenAI/Platform/OpenAI.php
@@ -26,8 +26,7 @@ protected function rawRequest(string $endpoint, array $body): ResponseInterface
 
         return $this->httpClient->request('POST', $url, [
             'auth_bearer' => $this->apiKey,
-            'headers' => ['Content-Type' => 'application/json'],
-            'body' => json_encode($body),
+            'json' => $body,
         ]);
     }
 }
diff --git a/src/Store/Azure/SearchStore.php b/src/Store/Azure/SearchStore.php
index 8bfcb636..b8ac89e2 100644
--- a/src/Store/Azure/SearchStore.php
+++ b/src/Store/Azure/SearchStore.php
@@ -54,7 +54,6 @@ private function request(string $endpoint, array $payload): array
         $response = $this->httpClient->request('POST', $url, [
             'headers' => [
                 'api-key' => $this->apiKey,
-                'Content-Type' => 'application/json',
             ],
             'query' => ['api-version' => $this->apiVersion],
             'json' => $payload,
diff --git a/src/Voyage/Platform/Voyage.php b/src/Voyage/Platform/Voyage.php
index b23dac28..330e73e3 100644
--- a/src/Voyage/Platform/Voyage.php
+++ b/src/Voyage/Platform/Voyage.php
@@ -18,7 +18,6 @@ public function __construct(
     public function request(array $body): array
     {
         $response = $this->httpClient->request('POST', 'https://api.voyageai.com/v1/embeddings', [
-            'headers' => ['Content-Type' => 'application/json'],
             'auth_bearer' => $this->apiKey,
             'json' => $body,
         ]);