diff --git a/package.json b/package.json
index eac9973..6c9b9ce 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@elevenlabs/cli",
-  "version": "0.5.0",
+  "version": "0.5.1",
   "description": "CLI tool to manage ElevenLabs agents",
   "type": "module",
   "keywords": [
diff --git a/src/__tests__/utils.test.ts b/src/__tests__/utils.test.ts
index b85f514..2162660 100644
--- a/src/__tests__/utils.test.ts
+++ b/src/__tests__/utils.test.ts
@@ -824,6 +824,90 @@ describe("Utils", () => {
       expect(afterPull).toEqual(originalWorkflow);
     });
 
+    it("should preserve model_usage keys in toCamelCaseKeys", () => {
+      const input = {
+        from_conversation_metadata: {
+          original_agent_reply: {
+            llm_usage: {
+              model_usage: {
+                "gpt_5.2": { input_tokens: 100, output_tokens: 50 },
+                "gpt-4o-mini": { input_tokens: 200, output_tokens: 100 },
+                "gemini-2.5-flash": { input_tokens: 300, output_tokens: 150 },
+                "claude-3-opus": { input_tokens: 400, output_tokens: 200 }
+              }
+            }
+          }
+        }
+      };
+
+      const result = toCamelCaseKeys(input);
+
+      expect(result).toEqual({
+        fromConversationMetadata: {
+          originalAgentReply: {
+            llmUsage: {
+              modelUsage: {
+                "gpt_5.2": { inputTokens: 100, outputTokens: 50 },          // preserved - model name
+                "gpt-4o-mini": { inputTokens: 200, outputTokens: 100 },      // preserved - model name
+                "gemini-2.5-flash": { inputTokens: 300, outputTokens: 150 }, // preserved - model name
+                "claude-3-opus": { inputTokens: 400, outputTokens: 200 }     // preserved - model name
+              }
+            }
+          }
+        }
+      });
+    });
+
+    it("should preserve modelUsage keys in toSnakeCaseKeys", () => {
+      const input = {
+        fromConversationMetadata: {
+          originalAgentReply: {
+            llmUsage: {
+              modelUsage: {
+                "gpt-5.2": { inputTokens: 100, outputTokens: 50 },
+                "gpt-4o-mini": { inputTokens: 200, outputTokens: 100 }
+              }
+            }
+          }
+        }
+      };
+
+      const result = toSnakeCaseKeys(input);
+
+      expect(result).toEqual({
+        from_conversation_metadata: {
+          original_agent_reply: {
+            llm_usage: {
+              model_usage: {
+                "gpt-5.2": { input_tokens: 100, output_tokens: 50 },   // preserved - model name
+                "gpt-4o-mini": { input_tokens: 200, output_tokens: 100 } // preserved - model name
+              }
+            }
+          }
+        }
+      });
+    });
+
+    it("should maintain round-trip conversion symmetry for model_usage", () => {
+      const original = {
+        from_conversation_metadata: {
+          original_agent_reply: {
+            llm_usage: {
+              model_usage: {
+                "gpt_5.2": { input_tokens: 100, output_tokens: 50 },
+                "gpt-4o-mini": { input_tokens: 200, output_tokens: 100 }
+              }
+            }
+          }
+        }
+      };
+
+      const afterPush = toCamelCaseKeys(original);
+      const afterPull = toSnakeCaseKeys(afterPush);
+
+      expect(afterPull).toEqual(original);
+    });
+
     it("should maintain round-trip conversion symmetry for dynamic_variables", () => {
       // Simulate pull → push cycle for tests
       const originalTestConfig = {
diff --git a/src/shared/utils.ts b/src/shared/utils.ts
index cac2116..7ac85a6 100644
--- a/src/shared/utils.ts
+++ b/src/shared/utils.ts
@@ -124,6 +124,7 @@ const PRESERVE_CHILD_KEYS = new Set([
   'request_headers', 'requestHeaders',
   'dynamic_variables', 'dynamicVariables',
   'language_presets', 'languagePresets',
+  'model_usage', 'modelUsage',
   'nodes',
   'edges',
 ]);