diff --git a/servers/Azure.Mcp.Server/changelog-entries/yunliu1-azapi-get-bad-request.yaml b/servers/Azure.Mcp.Server/changelog-entries/yunliu1-azapi-get-bad-request.yaml
new file mode 100644
index 0000000000..fe8afd1721
--- /dev/null
+++ b/servers/Azure.Mcp.Server/changelog-entries/yunliu1-azapi-get-bad-request.yaml
@@ -0,0 +1,3 @@
+changes:
+  - section: "Bugs Fixed"
+    description: "Fixed `azureterraform_azapi_get` returning `500 InternalServerError` for invalid resource type or API version inputs. The tool now returns `400 BadRequest` with an actionable message, enabling agents to auto-correct and retry with valid inputs."
diff --git a/tools/Azure.Mcp.Tools.AzureTerraform/src/Commands/AzApiDocsGetCommand.cs b/tools/Azure.Mcp.Tools.AzureTerraform/src/Commands/AzApiDocsGetCommand.cs
index 04b416f5a3..0368b092a7 100644
--- a/tools/Azure.Mcp.Tools.AzureTerraform/src/Commands/AzApiDocsGetCommand.cs
+++ b/tools/Azure.Mcp.Tools.AzureTerraform/src/Commands/AzApiDocsGetCommand.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+using System.IO;
 using System.Net;
 using Azure.Mcp.Tools.AzureTerraform.Models;
 using Azure.Mcp.Tools.AzureTerraform.Options;
@@ -55,6 +56,12 @@ protected override AzApiDocsOptions BindOptions(ParseResult parseResult)
         };
     }
 
+    protected override HttpStatusCode GetStatusCode(Exception ex) => ex switch
+    {
+        InvalidDataException => HttpStatusCode.BadRequest,
+        _ => base.GetStatusCode(ex)
+    };
+
     public override async Task<CommandResponse> ExecuteAsync(
         CommandContext context,
         ParseResult parseResult,
diff --git a/tools/Azure.Mcp.Tools.AzureTerraform/tests/Azure.Mcp.Tools.AzureTerraform.Tests/AzApiDocsGetCommandTests.cs b/tools/Azure.Mcp.Tools.AzureTerraform/tests/Azure.Mcp.Tools.AzureTerraform.Tests/AzApiDocsGetCommandTests.cs
index cdb65e5222..ae05690efd 100644
--- a/tools/Azure.Mcp.Tools.AzureTerraform/tests/Azure.Mcp.Tools.AzureTerraform.Tests/AzApiDocsGetCommandTests.cs
+++ b/tools/Azure.Mcp.Tools.AzureTerraform/tests/Azure.Mcp.Tools.AzureTerraform.Tests/AzApiDocsGetCommandTests.cs
@@ -136,7 +136,7 @@ public async Task ExecuteAsync_ServiceThrows_HandlesException()
 
         var response = await ExecuteCommandAsync("--resource-type", "Microsoft.Fake/nonexistent");
 
-        Assert.NotEqual(HttpStatusCode.OK, response.Status);
+        Assert.Equal(HttpStatusCode.BadRequest, response.Status);
     }
 
     [Theory]
diff --git a/tools/Azure.Mcp.Tools.BicepSchema/src/Services/ResourceProperties/ResourceVisitor.cs b/tools/Azure.Mcp.Tools.BicepSchema/src/Services/ResourceProperties/ResourceVisitor.cs
index e31b5a63ac..1471eab722 100644
--- a/tools/Azure.Mcp.Tools.BicepSchema/src/Services/ResourceProperties/ResourceVisitor.cs
+++ b/tools/Azure.Mcp.Tools.BicepSchema/src/Services/ResourceProperties/ResourceVisitor.cs
@@ -86,12 +86,13 @@ public string[] GetResourceApiVersions(string resourceTypeName)
     {
         (string providerName, _, _) = ResourceParser.ParseResourceType(resourceTypeName);
 
-        if (!GetAllResourceTypesAndVersionsByProvider().TryGetValue(providerName, out ProviderResourceTypes? provider))
+        if (!GetAllResourceTypesAndVersionsByProvider().TryGetValue(providerName, out ProviderResourceTypes? provider)
+            || !provider.ResourceTypes.TryGetValue(resourceTypeName.ToLowerInvariant(), out UniqueResourceType? uniqueResourceType))
         {
-            throw new Exception($"Resource type {resourceTypeName} not found.");
+            throw new InvalidDataException($"Resource type {resourceTypeName} not found.");
         }
 
-        return [.. provider.ResourceTypes[resourceTypeName.ToLowerInvariant()].ApiVersions];
+        return [.. uniqueResourceType.ApiVersions];
     }
 
     public TypesDefinitionResult LoadSingleResource(string resourceTypeName, string apiVersion)
diff --git a/tools/Azure.Mcp.Tools.BicepSchema/tests/Azure.Mcp.Tools.BicepSchema.Tests/GetSchemaTests.cs b/tools/Azure.Mcp.Tools.BicepSchema/tests/Azure.Mcp.Tools.BicepSchema.Tests/GetSchemaTests.cs
index 2a9188f864..67f467bb21 100644
--- a/tools/Azure.Mcp.Tools.BicepSchema/tests/Azure.Mcp.Tools.BicepSchema.Tests/GetSchemaTests.cs
+++ b/tools/Azure.Mcp.Tools.BicepSchema/tests/Azure.Mcp.Tools.BicepSchema.Tests/GetSchemaTests.cs
@@ -33,7 +33,7 @@ public void GetResourcePropertySchema_ShouldThrowOnNotFound()
         SchemaGenerator.ConfigureServices(serviceCollection);
         IServiceProvider serviceProvider = serviceCollection.BuildServiceProvider();
 
-        var exception = Assert.Throws<Exception>(() =>
+        var exception = Assert.Throws<InvalidDataException>(() =>
         {
             TypesDefinitionResult result = SchemaGenerator.GetResourceTypeDefinitions(serviceProvider, "Microsoft.Unknown/virtualRandom");
             _ = SchemaGenerator.GetResponse(result);