feat: Add reasoning.effort: none parameter for gpt-5.1

.changeset/olive-waves-type.md

@@ -0,0 +1,6 @@
+---
+'@openai/agents-openai': patch
+'@openai/agents-core': patch
+---
+
+feat: Add reasoning.effort: none parameter for gpt-5.1

examples/basic/hello-world-gpt-5.1.ts

@@ -0,0 +1,50 @@
+import {
+  Agent,
+  OpenAIChatCompletionsModel,
+  run,
+  withTrace,
+} from '@openai/agents';
+import OpenAI from 'openai';
+import { z } from 'zod';
+
+const output = z.object({
+  title: z.string(),
+  description: z.string(),
+});
+
+async function main() {
+  withTrace('GPT-5.1 None Reasoning Assistant', async () => {
+    const prompt =
+      'Tell me about recursion in programming in a few sentences. Quickly responding with a single answer is fine.';
+    const agent = new Agent({
+      name: 'GPT-5.1 Responses Assistant',
+      model: 'gpt-5.1',
+      instructions: "You're a helpful assistant.",
+      modelSettings: {
+        reasoning: { effort: 'none' },
+        text: { verbosity: 'low' },
+      },
+      outputType: output,
+    });
+    const result = await run(agent, prompt);
+    console.log(result.finalOutput);
+
+    const completionsAgent = new Agent({
+      name: 'GPT-5.1 Chat Completions Assistant',
+      model: new OpenAIChatCompletionsModel(new OpenAI(), 'gpt-5.1'),
+      instructions: "You're a helpful assistant.",
+      modelSettings: {
+        reasoning: { effort: 'none' },
+        text: { verbosity: 'low' },
+      },
+      outputType: output,
+    });
+    const completionsResult = await run(completionsAgent, prompt);
+    console.log(completionsResult.finalOutput);
+  });
+}
+
+main().catch((error) => {
+  console.error(error);
+  process.exit(1);
+});

examples/basic/hello-world-gpt-5.ts

@@ -1,4 +1,9 @@
-import { Agent, OpenAIChatCompletionsModel, run } from '@openai/agents';
+import {
+  Agent,
+  OpenAIChatCompletionsModel,
+  run,
+  withTrace,
+} from '@openai/agents';
 import OpenAI from 'openai';
 import { z } from 'zod';
 
@@ -8,59 +13,61 @@ const output = z.object({
 });
 
 async function main() {
-  const prompt =
-    'Tell me about recursion in programming. Quickly responding with a single answer is fine.';
+  withTrace('GPT-5 Assistant', async () => {
+    const prompt =
+      'Tell me about recursion in programming in a few sentences. Quickly responding with a single answer is fine.';
 
-  const agent = new Agent({
-    name: 'GPT-5 Assistant',
-    model: 'gpt-5',
-    instructions: "You're a helpful assistant.",
-    modelSettings: {
-      reasoning: { effort: 'minimal' },
-      text: { verbosity: 'low' },
-    },
-    outputType: output,
-  });
+    const agent = new Agent({
+      name: 'GPT-5 Assistant',
+      model: 'gpt-5',
+      instructions: "You're a helpful assistant.",
+      modelSettings: {
+        reasoning: { effort: 'minimal' },
+        text: { verbosity: 'low' },
+      },
+      outputType: output,
+    });
 
-  const result = await run(agent, prompt);
-  console.log(result.finalOutput);
+    const result = await run(agent, prompt);
+    console.log(result.finalOutput);
 
-  // The following code works in the same way:
-  // const agent2 = agent.clone({
-  //   modelSettings: {
-  //     providerData: {
-  //       reasoning: { effort: 'minimal' },
-  //       text: { verbosity: 'low' },
-  //     }
-  //   },
-  // });
-  // const result2 = await run(agent2, prompt);
-  // console.log(result2.finalOutput);
+    // The following code works in the same way:
+    // const agent2 = agent.clone({
+    //   modelSettings: {
+    //     providerData: {
+    //       reasoning: { effort: 'minimal' },
+    //       text: { verbosity: 'low' },
+    //     }
+    //   },
+    // });
+    // const result2 = await run(agent2, prompt);
+    // console.log(result2.finalOutput);
 
-  const completionsAgent = new Agent({
-    name: 'GPT-5 Assistant',
-    model: new OpenAIChatCompletionsModel(new OpenAI(), 'gpt-5'),
-    instructions: "You're a helpful assistant.",
-    modelSettings: {
-      reasoning: { effort: 'minimal' },
-      text: { verbosity: 'low' },
-    },
-    outputType: output,
-  });
-  const completionsResult = await run(completionsAgent, prompt);
-  console.log(completionsResult.finalOutput);
+    const completionsAgent = new Agent({
+      name: 'GPT-5 Assistant',
+      model: new OpenAIChatCompletionsModel(new OpenAI(), 'gpt-5'),
+      instructions: "You're a helpful assistant.",
+      modelSettings: {
+        reasoning: { effort: 'minimal' },
+        text: { verbosity: 'low' },
+      },
+      outputType: output,
+    });
+    const completionsResult = await run(completionsAgent, prompt);
+    console.log(completionsResult.finalOutput);
 
-  // The following code works in the same way:
-  // const completionsAgent2 = completionsAgent.clone({
-  //   modelSettings: {
-  //     providerData: {
-  //       reasoning_effort: 'minimal',
-  //       verbosity: 'low',
-  //     }
-  //   },
-  // });
-  // const completionsResult2 = await run(completionsAgent2, prompt);
-  // console.log(completionsResult2.finalOutput);
+    // The following code works in the same way:
+    // const completionsAgent2 = completionsAgent.clone({
+    //   modelSettings: {
+    //     providerData: {
+    //       reasoning_effort: 'minimal',
+    //       verbosity: 'low',
+    //     }
+    //   },
+    // });
+    // const completionsResult2 = await run(completionsAgent2, prompt);
+    // console.log(completionsResult2.finalOutput);
+  });
 }
 
 main().catch((error) => {

examples/basic/package.json

@@ -12,6 +12,7 @@
     "start:dynamic-system-prompt": "tsx dynamic-system-prompt.ts",
     "start:hello-world": "tsx hello-world.ts",
     "start:hello-world-gpt-5": "tsx hello-world-gpt-5.ts",
+    "start:hello-world-gpt-5.1": "tsx hello-world-gpt-5.1.ts",
     "start:hello-world-gpt-oss": "tsx hello-world-gpt-oss.ts",
     "start:lifecycle-example": "tsx lifecycle-example.ts",
     "start:local-image": "tsx local-image.ts",

packages/agents-core/src/model.ts

@@ -30,7 +30,8 @@ export type ModelSettingsToolChoice =
  * Reducing reasoning effort can result in faster responses and fewer tokens used on reasoning in a response.
  */
 export type ModelSettingsReasoningEffort =
-  | 'minimal'
+  | 'none' // for gpt-5.1
+  | 'minimal' // for gpt-5
   | 'low'
   | 'medium'
   | 'high'

packages/agents-openai/test/openaiChatCompletionsModel.test.ts

@@ -283,6 +283,35 @@ describe('OpenAIChatCompletionsModel', () => {
     expect(options).toEqual({ headers: HEADERS, signal: undefined });
   });
 
+  it('passes none reasoning effort through to chat completions payloads', async () => {
+    const client = new FakeClient();
+    const response = {
+      id: 'gpt-5.1-response',
+      choices: [{ message: { content: 'done' } }],
+      usage: { prompt_tokens: 0, completion_tokens: 0, total_tokens: 0 },
+    } as any;
+    client.chat.completions.create.mockResolvedValue(response);
+
+    const model = new OpenAIChatCompletionsModel(client as any, 'gpt-5.1');
+    const req: any = {
+      input: 'prompt',
+      modelSettings: {
+        reasoning: { effort: 'none' },
+      },
+      tools: [],
+      outputType: 'text',
+      handoffs: [],
+      tracing: false,
+    };
+
+    await withTrace('gpt-5.1 none', () => model.getResponse(req));
+
+    expect(client.chat.completions.create).toHaveBeenCalledTimes(1);
+    const [args, options] = client.chat.completions.create.mock.calls[0];
+    expect(args.reasoning_effort).toBe('none');
+    expect(options).toEqual({ headers: HEADERS, signal: undefined });
+  });
+
   it('handles function tool calls', async () => {
     const client = new FakeClient();
     const response = {

packages/agents-openai/test/openaiResponsesModel.test.ts

@@ -253,6 +253,43 @@ describe('OpenAIResponsesModel', () => {
     });
   });
 
+  it('passes none reasoning effort to the Responses API payload', async () => {
+    await withTrace('test', async () => {
+      const fakeResponse = {
+        id: 'res-none',
+        usage: {
+          input_tokens: 1,
+          output_tokens: 1,
+          total_tokens: 2,
+        },
+        output: [],
+      };
+      const createMock = vi.fn().mockResolvedValue(fakeResponse);
+      const fakeClient = {
+        responses: { create: createMock },
+      } as unknown as OpenAI;
+      const model = new OpenAIResponsesModel(fakeClient, 'gpt-5.1');
+      const request = {
+        systemInstructions: undefined,
+        input: 'hi',
+        modelSettings: {
+          reasoning: { effort: 'none' },
+        },
+        tools: [],
+        outputType: 'text',
+        handoffs: [],
+        tracing: false,
+        signal: undefined,
+      };
+
+      await model.getResponse(request as any);
+
+      expect(createMock).toHaveBeenCalledTimes(1);
+      const [args] = createMock.mock.calls[0];
+      expect(args.reasoning).toEqual({ effort: 'none' });
+    });
+  });
+
   it('getStreamedResponse yields events and calls client with stream flag', async () => {
     await withTrace('test', async () => {
       const fakeResponse = { id: 'res2', usage: {}, output: [] };