diff --git a/src/Web/Controllers/Commands/CommandController.cs b/src/Web/Controllers/Commands/CommandController.cs
index 8505698..52b2241 100644
--- a/src/Web/Controllers/Commands/CommandController.cs
+++ b/src/Web/Controllers/Commands/CommandController.cs
@@ -27,7 +27,7 @@ public class CommandController : ControllerBase
             Params = cmd.Parameters.Select(dict => new ResponseCommandParam()
             {
                 Summary = dict.Value.Summary,
-                Default = dict.Value.DefaultValue,
+                Default = string.IsNullOrEmpty(dict.Value.DefaultValue) ? null : dict.Value.DefaultValue,
                 Type = dict.Value.Type
             }).ToList()
         });
diff --git a/src/Web/Controllers/Commands/ResponseCommandParam.cs b/src/Web/Controllers/Commands/ResponseCommandParam.cs
index 2acbca5..c99a113 100644
--- a/src/Web/Controllers/Commands/ResponseCommandParam.cs
+++ b/src/Web/Controllers/Commands/ResponseCommandParam.cs
@@ -8,7 +8,8 @@ public record ResponseCommandParam
     public string Summary { get; set; }
     
     [JsonPropertyName("default")]
-    public string Default { get; set; }
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public string? Default { get; set; }
     
     [JsonPropertyName("type")]
     public string Type { get; set; }