-public async Task CanSetExtraHeaders()
+public void CanSetExtraHeaders()
 {
-    var result = await bidi.Network.SetExtraHeadersAsync([new Header("x-test-header", "test-value")]);
-
-    Assert.That(result, Is.Not.Null);
+    Assert.That(async () => await bidi.Network.SetExtraHeadersAsync([new Header("x-test-header", "test-value")]), Throws.Nothing);
 }

 public async Task<EmptyResult> SetExtraHeadersAsync(IEnumerable<Header> headers, SetExtraHeadersOptions? options = null)
 {
+    if (headers is null)
+    {
+        throw new ArgumentNullException(nameof(headers));
+    }
+
     var @params = new SetExtraHeadersParameters(headers, options?.Contexts, options?.UserContexts);
 
     return await Broker.ExecuteCommandAsync<SetExtraHeadersCommand, EmptyResult>(new SetExtraHeadersCommand(@params), options).ConfigureAwait(false);
 }