diff --git a/packages/ai/src/llm/providers/gateway.ts b/packages/ai/src/llm/providers/gateway.ts
index bc532b862..8d18d51ad 100644
--- a/packages/ai/src/llm/providers/gateway.ts
+++ b/packages/ai/src/llm/providers/gateway.ts
@@ -6,7 +6,6 @@ export const DEFAULT_ANTHROPIC_OPTIONS = {
   gateway: {
     order: ['bedrock', 'anthropic', 'vertex'],
   },
-  headers: {},
   anthropic: { cacheControl: { type: 'ephemeral' } },
 };
 
@@ -15,7 +14,7 @@ export const DEFAULT_OPENAI_OPTIONS = {
     order: ['openai'],
   },
   openai: {
-    parallelToolCalls: false,
+    // parallelToolCalls: false,
     reasoningEffort: 'minimal',
     verbosity: 'low',
   },
diff --git a/packages/ai/src/steps/analyst-agent-steps/generate-chat-title-step/generate-chat-title-step.ts b/packages/ai/src/steps/analyst-agent-steps/generate-chat-title-step/generate-chat-title-step.ts
index 08f490235..35e3df743 100644
--- a/packages/ai/src/steps/analyst-agent-steps/generate-chat-title-step/generate-chat-title-step.ts
+++ b/packages/ai/src/steps/analyst-agent-steps/generate-chat-title-step/generate-chat-title-step.ts
@@ -3,8 +3,8 @@ import { generateObject } from 'ai';
 import type { ModelMessage } from 'ai';
 import { wrapTraced } from 'braintrust';
 import { z } from 'zod';
-import { GPT5Nano } from '../../../llm';
-import { DEFAULT_OPENAI_OPTIONS } from '../../../llm/providers/gateway';
+import { Haiku35 } from '../../../llm';
+import { DEFAULT_ANTHROPIC_OPTIONS } from '../../../llm/providers/gateway';
 
 // Zod-first: define input/output schemas and export inferred types
 export const generateChatTitleParamsSchema = z.object({
@@ -56,10 +56,10 @@ async function generateTitleWithLLM(messages: ModelMessage[]): Promise<string> {
     const tracedChatTitle = wrapTraced(
       async () => {
         const { object } = await generateObject({
-          model: GPT5Nano,
+          model: Haiku35,
           schema: llmOutputSchema,
           messages: titleMessages,
-          providerOptions: DEFAULT_OPENAI_OPTIONS,
+          providerOptions: DEFAULT_ANTHROPIC_OPTIONS,
         });
 
         return object;