diff --git a/pkg/loader/loader.go b/pkg/loader/loader.go
index e5a9bb1e..51c74921 100644
--- a/pkg/loader/loader.go
+++ b/pkg/loader/loader.go
@@ -184,13 +184,13 @@ func readTool(ctx context.Context, prg *types.Program, base *source, targetToolN
 			mainTool = tool
 		}
 
-		if existing, ok := localTools[tool.Parameters.Name]; ok {
+		if existing, ok := localTools[strings.ToLower(tool.Parameters.Name)]; ok {
 			return types.Tool{}, parser.NewErrLine(tool.Source.Location, tool.Source.LineNo,
 				fmt.Errorf("duplicate tool name [%s] in %s found at lines %d and %d", tool.Parameters.Name, tool.Source.Location,
 					tool.Source.LineNo, existing.Source.LineNo))
 		}
 
-		localTools[tool.Parameters.Name] = tool
+		localTools[strings.ToLower(tool.Parameters.Name)] = tool
 	}
 
 	return link(ctx, prg, base, mainTool, localTools)
diff --git a/pkg/tests/runner_test.go b/pkg/tests/runner_test.go
index 33c3d2d3..76c5c5fa 100644
--- a/pkg/tests/runner_test.go
+++ b/pkg/tests/runner_test.go
@@ -633,6 +633,13 @@ func TestContext(t *testing.T) {
 	assert.Equal(t, "TEST RESULT CALL: 1", x)
 }
 
+func TestCase(t *testing.T) {
+	runner := tester.NewRunner(t)
+	x, err := runner.Run("", "")
+	require.NoError(t, err)
+	assert.Equal(t, "TEST RESULT CALL: 1", x)
+}
+
 func TestContextArg(t *testing.T) {
 	runner := tester.NewRunner(t)
 	x, err := runner.Run("", `{
diff --git a/pkg/tests/testdata/TestCase/call1.golden b/pkg/tests/testdata/TestCase/call1.golden
new file mode 100644
index 00000000..9a760d4c
--- /dev/null
+++ b/pkg/tests/testdata/TestCase/call1.golden
@@ -0,0 +1,37 @@
+`{
+  "Model": "gpt-4-turbo-preview",
+  "InternalSystemPrompt": null,
+  "Tools": [
+    {
+      "function": {
+        "toolID": "testdata/TestCase/test.gpt:6",
+        "name": "bob",
+        "description": "I'm Bob, a friendly guy.",
+        "parameters": {
+          "properties": {
+            "question": {
+              "description": "The question to ask Bob.",
+              "type": "string"
+            }
+          },
+          "type": "object"
+        }
+      }
+    }
+  ],
+  "Messages": [
+    {
+      "role": "system",
+      "content": [
+        {
+          "text": "Ask Bob how he is doing and let me know exactly what he said."
+        }
+      ]
+    }
+  ],
+  "MaxTokens": 0,
+  "Temperature": null,
+  "JSONResponse": false,
+  "Grammar": "",
+  "Cache": null
+}`
diff --git a/pkg/tests/testdata/TestCase/test.gpt b/pkg/tests/testdata/TestCase/test.gpt
new file mode 100644
index 00000000..be1914e1
--- /dev/null
+++ b/pkg/tests/testdata/TestCase/test.gpt
@@ -0,0 +1,12 @@
+tools: Bob
+
+Ask Bob how he is doing and let me know exactly what he said.
+
+---
+name: Bob
+description: I'm Bob, a friendly guy.
+args: question: The question to ask Bob.
+
+#!/bin/bash
+
+echo "Thanks for asking ${question}, I'm doing great fellow friendly AI tool!"