diff --git a/src/main/java/ee/carlrobert/llm/client/ollama/OllamaClient.java b/src/main/java/ee/carlrobert/llm/client/ollama/OllamaClient.java
index 3918570..18adde8 100644
--- a/src/main/java/ee/carlrobert/llm/client/ollama/OllamaClient.java
+++ b/src/main/java/ee/carlrobert/llm/client/ollama/OllamaClient.java
@@ -244,10 +244,15 @@ private void processStreamRequest(
   private HttpRequest buildPostHttpRequest(
       Object request,
       String path) throws JsonProcessingException {
-    return HttpRequest.newBuilder(URI.create(BASE_URL + path))
+    var requestBuilder = HttpRequest.newBuilder(URI.create(BASE_URL + path))
         .POST(HttpRequest.BodyPublishers.ofString(new ObjectMapper().writeValueAsString(request)))
-        .header("Content-Type", "application/json")
-        .timeout(Duration.ofSeconds(30))
+        .header("Content-Type", "application/x-ndjson");
+
+    if (apiKey != null) {
+      requestBuilder.header("Authorization", "Bearer " + apiKey);
+    }
+
+    return requestBuilder.timeout(Duration.ofSeconds(30))
         .build();
   }