🔧 fix: Clean empty strings from model_parameters for Agents/OpenAI (#11248)

packages/api/src/endpoints/openai/llm.spec.ts

@@ -56,6 +56,77 @@ describe('getOpenAILLMConfig', () => {
     });
   });
 
+  describe('Empty String Handling (Issue Fix)', () => {
+    it('should remove empty string values for numeric parameters', () => {
+      const result = getOpenAILLMConfig({
+        apiKey: 'test-api-key',
+        streaming: true,
+        modelOptions: {
+          model: 'gpt-4',
+          temperature: '' as unknown as number,
+          topP: '' as unknown as number,
+          max_tokens: '' as unknown as number,
+        },
+      });
+
+      expect(result.llmConfig).not.toHaveProperty('temperature');
+      expect(result.llmConfig).not.toHaveProperty('topP');
+      expect(result.llmConfig).not.toHaveProperty('maxTokens');
+      expect(result.llmConfig).not.toHaveProperty('max_tokens');
+    });
+
+    it('should remove empty string values for frequency and presence penalties', () => {
+      const result = getOpenAILLMConfig({
+        apiKey: 'test-api-key',
+        streaming: true,
+        modelOptions: {
+          model: 'gpt-4',
+          frequency_penalty: '' as unknown as number,
+          presence_penalty: '' as unknown as number,
+        },
+      });
+
+      expect(result.llmConfig).not.toHaveProperty('frequencyPenalty');
+      expect(result.llmConfig).not.toHaveProperty('presencePenalty');
+      expect(result.llmConfig).not.toHaveProperty('frequency_penalty');
+      expect(result.llmConfig).not.toHaveProperty('presence_penalty');
+    });
+
+    it('should preserve valid numeric values while removing empty strings', () => {
+      const result = getOpenAILLMConfig({
+        apiKey: 'test-api-key',
+        streaming: true,
+        modelOptions: {
+          model: 'gpt-4',
+          temperature: 0.7,
+          topP: '' as unknown as number,
+          max_tokens: 4096,
+        },
+      });
+
+      expect(result.llmConfig).toHaveProperty('temperature', 0.7);
+      expect(result.llmConfig).not.toHaveProperty('topP');
+      expect(result.llmConfig).toHaveProperty('maxTokens', 4096);
+    });
+
+    it('should preserve zero values (not treat them as empty)', () => {
+      const result = getOpenAILLMConfig({
+        apiKey: 'test-api-key',
+        streaming: true,
+        modelOptions: {
+          model: 'gpt-4',
+          temperature: 0,
+          frequency_penalty: 0,
+          presence_penalty: 0,
+        },
+      });
+
+      expect(result.llmConfig).toHaveProperty('temperature', 0);
+      expect(result.llmConfig).toHaveProperty('frequencyPenalty', 0);
+      expect(result.llmConfig).toHaveProperty('presencePenalty', 0);
+    });
+  });
+
   describe('OpenAI Reasoning Models (o1/o3/gpt-5)', () => {
     const reasoningModels = [
       'o1',

packages/api/src/endpoints/openai/llm.ts

@@ -139,6 +139,12 @@ export function getOpenAILLMConfig({
 }): Pick<t.LLMConfigResult, 'llmConfig' | 'tools'> & {
   azure?: t.AzureOptions;
 } {
+  /** Clean empty strings from model options (e.g., temperature: "" should be removed) */
+  const cleanedModelOptions = removeNullishValues(
+    _modelOptions,
+    true,
+  ) as Partial<t.OpenAIParameters>;
+
   const {
     reasoning_effort,
     reasoning_summary,
@@ -147,7 +153,7 @@ export function getOpenAILLMConfig({
     frequency_penalty,
     presence_penalty,
     ...modelOptions
-  } = _modelOptions;
+  } = cleanedModelOptions;
 
   const llmConfig = Object.assign(
     {