diff --git a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.EndChat.cs b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.EndChat.cs
index f514e3a..0c8459a 100644
--- a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.EndChat.cs
+++ b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.EndChat.cs
@@ -25,7 +25,7 @@ public async Task ShouldEndChatAsync()
                 Request.Create()
                 .UsingPost()
                     .WithPath("/api/chats/end")
-                    .WithHeader("Authorization", $"Bearer {this.apiKey}")
+                    .WithHeader("X-API-Key", this.apiKey)
                     .WithHeader("Content-Type", "application/json; charset=utf-8")
                     .WithBody(expectedBody)
                     )
diff --git a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StartChat.cs b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StartChat.cs
index 9182833..69431f7 100644
--- a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StartChat.cs
+++ b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StartChat.cs
@@ -31,7 +31,7 @@ public async Task ShouldStartChatAsync()
                 Request.Create()
                 .UsingPost()
                     .WithPath("/api/chats/start")
-                    .WithHeader("Authorization", $"Bearer {this.apiKey}")
+                    .WithHeader("X-API-Key", this.apiKey)
                     .WithHeader("Content-Type", "application/json; charset=utf-8")
                     .WithBody(expectedBody))
                 .RespondWith(
diff --git a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StreamChat.cs b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StreamChat.cs
index e35e655..167fa34 100644
--- a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StreamChat.cs
+++ b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V1/Chats/ChatClientV1Tests.StreamChat.cs
@@ -30,7 +30,7 @@ public async Task ShouldStreamChatAsync()
                 Request.Create()
                 .UsingPost()
                     .WithPath("/api/chats/stream")
-                    .WithHeader("Authorization", $"Bearer {this.apiKey}")
+                    .WithHeader("X-API-Key", this.apiKey)
                     .WithHeader("Content-Type", "application/json; charset=utf-8")
                     .WithBody(expectedBody))
                 .RespondWith(
diff --git a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.EndChat.cs b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.EndChat.cs
index d220dc5..b984322 100644
--- a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.EndChat.cs
+++ b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.EndChat.cs
@@ -25,7 +25,7 @@ public async Task ShouldEndChatAsync()
                 Request.Create()
                 .UsingPost()
                     .WithPath("/api/v2/chats/end")
-                    .WithHeader("Authorization", $"Bearer {this.apiKey}")
+                    .WithHeader("X-API-Key", this.apiKey)
                     .WithHeader("Content-Type", "application/json; charset=utf-8")
                     .WithBody(expectedBody)
                     )
diff --git a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StartChat.cs b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StartChat.cs
index 1797144..6f33faa 100644
--- a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StartChat.cs
+++ b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StartChat.cs
@@ -37,7 +37,7 @@ public async Task ShouldStartChatAsync()
                 Request.Create()
                 .UsingPost()
                     .WithPath("/api/v2/chats/start")
-                    .WithHeader("Authorization", $"Bearer {this.apiKey}")
+                    .WithHeader("X-API-Key", this.apiKey)
                     .WithHeader("Content-Type", "application/json; charset=utf-8")
                     .WithBody(expectedBody))
                 .RespondWith(
diff --git a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StreamChat.cs b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StreamChat.cs
index 7fd7c01..4386750 100644
--- a/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StreamChat.cs
+++ b/Standard.AI.PeerLLM.Tests.Acceptance/Clients/V2/Chats/ChatClientV2Tests.StreamChat.cs
@@ -30,7 +30,7 @@ public async Task ShouldStreamChatAsync()
                 Request.Create()
                 .UsingPost()
                     .WithPath("/api/v2/chats/stream")
-                    .WithHeader("Authorization", $"Bearer {this.apiKey}")
+                    .WithHeader("X-API-Key", this.apiKey)
                     .WithHeader("Content-Type", "application/json; charset=utf-8")
                     .WithBody(expectedBody))
                 .RespondWith(
diff --git a/Standard.AI.PeerLLM/Brokers/PeerLLMs/PeerLLMBroker.cs b/Standard.AI.PeerLLM/Brokers/PeerLLMs/PeerLLMBroker.cs
index 5b3dfb8..9de81ff 100644
--- a/Standard.AI.PeerLLM/Brokers/PeerLLMs/PeerLLMBroker.cs
+++ b/Standard.AI.PeerLLM/Brokers/PeerLLMs/PeerLLMBroker.cs
@@ -5,7 +5,6 @@
 using System;
 using System.Collections.Generic;
 using System.Net.Http;
-using System.Net.Http.Headers;
 using System.Runtime.CompilerServices;
 using System.Text;
 using System.Text.Json;
@@ -106,10 +105,9 @@ private HttpClient SetupHttpClient()
 
             if (!string.IsNullOrWhiteSpace(this.peerLLMConfiguration.ApiKey))
             {
-                httpClient.DefaultRequestHeaders.Authorization =
-                new AuthenticationHeaderValue(
-                    scheme: "Bearer",
-                    parameter: this.peerLLMConfiguration.ApiKey);
+                httpClient.DefaultRequestHeaders.Add(
+                    name: "X-API-Key",
+                    value: this.peerLLMConfiguration.ApiKey);
             }
 
             return httpClient;