diff --git a/extensions/copilot/src/extension/byok/node/test/openAIEndpoint.spec.ts b/extensions/copilot/src/extension/byok/node/test/openAIEndpoint.spec.ts
index 21cb575597c..ff528736e0b 100644
--- a/extensions/copilot/src/extension/byok/node/test/openAIEndpoint.spec.ts
+++ b/extensions/copilot/src/extension/byok/node/test/openAIEndpoint.spec.ts
@@ -86,9 +86,11 @@ describe('OpenAIEndpoint - Reasoning Properties', () => {
 
 	describe('CAPI mode (useResponsesApi = false)', () => {
 		it('should set cot_id and cot_summary properties when processing thinking content', () => {
-			accessor.get(IConfigurationService).setConfig(ConfigKey.UseResponsesApi, false);
 			const endpoint = instaService.createInstance(OpenAIEndpoint,
-				modelMetadata,
+				{
+					...modelMetadata,
+					supported_endpoints: [ModelSupportedEndpoint.ChatCompletions]
+				},
 				'test-api-key',
 				'https://api.openai.com/v1/chat/completions');
 
@@ -105,9 +107,11 @@ describe('OpenAIEndpoint - Reasoning Properties', () => {
 		});
 
 		it('should handle multiple messages with thinking content', () => {
-			accessor.get(IConfigurationService).setConfig(ConfigKey.UseResponsesApi, false);
 			const endpoint = instaService.createInstance(OpenAIEndpoint,
-				modelMetadata,
+				{
+					...modelMetadata,
+					supported_endpoints: [ModelSupportedEndpoint.ChatCompletions]
+				},
 				'test-api-key',
 				'https://api.openai.com/v1/chat/completions');
 
@@ -136,7 +140,6 @@ describe('OpenAIEndpoint - Reasoning Properties', () => {
 
 	describe('Responses API mode (useResponsesApi = true)', () => {
 		it('should preserve reasoning object when thinking is supported', () => {
-			accessor.get(IConfigurationService).setConfig(ConfigKey.UseResponsesApi, true);
 			accessor.get(IConfigurationService).setConfig(ConfigKey.ResponsesApiReasoningEffort, 'medium');
 			accessor.get(IConfigurationService).setConfig(ConfigKey.ResponsesApiReasoningSummary, 'detailed');
 			const endpoint = instaService.createInstance(OpenAIEndpoint,
@@ -167,7 +170,6 @@ describe('OpenAIEndpoint - Reasoning Properties', () => {
 				}
 			};
 
-			accessor.get(IConfigurationService).setConfig(ConfigKey.UseResponsesApi, true);
 			accessor.get(IConfigurationService).setConfig(ConfigKey.ResponsesApiReasoningEffort, 'medium');
 			accessor.get(IConfigurationService).setConfig(ConfigKey.ResponsesApiReasoningSummary, 'detailed');
 			const endpoint = instaService.createInstance(OpenAIEndpoint,
diff --git a/extensions/copilot/src/extension/byok/vscode-node/openAIProvider.ts b/extensions/copilot/src/extension/byok/vscode-node/openAIProvider.ts
index 9d3667bb203..7177606b4bb 100644
--- a/extensions/copilot/src/extension/byok/vscode-node/openAIProvider.ts
+++ b/extensions/copilot/src/extension/byok/vscode-node/openAIProvider.ts
@@ -2,11 +2,9 @@
  *  Copyright (c) Microsoft Corporation. All rights reserved.
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
-import { ConfigKey, IConfigurationService } from '../../../platform/configuration/common/configurationService';
 import { IChatModelInformation, ModelSupportedEndpoint } from '../../../platform/endpoint/common/endpointProvider';
 import { ILogService } from '../../../platform/log/common/logService';
 import { IFetcherService } from '../../../platform/networking/common/fetcherService';
-import { IExperimentationService } from '../../../platform/telemetry/common/nullExperimentationService';
 import { IInstantiationService } from '../../../util/vs/platform/instantiation/common/instantiation';
 import { BYOKAuthType, BYOKKnownModels, BYOKModelCapabilities } from '../common/byokProvider';
 import { BaseOpenAICompatibleLMProvider } from './baseOpenAICompatibleProvider';
@@ -21,8 +19,6 @@ export class OAIBYOKLMProvider extends BaseOpenAICompatibleLMProvider {
 		@IFetcherService _fetcherService: IFetcherService,
 		@ILogService _logService: ILogService,
 		@IInstantiationService _instantiationService: IInstantiationService,
-		@IConfigurationService private readonly _configurationService: IConfigurationService,
-		@IExperimentationService private readonly _expService: IExperimentationService
 	) {
 		super(
 			BYOKAuthType.GlobalApiKey,
@@ -38,13 +34,10 @@ export class OAIBYOKLMProvider extends BaseOpenAICompatibleLMProvider {
 
 	protected override async getModelInfo(modelId: string, apiKey: string | undefined, modelCapabilities?: BYOKModelCapabilities): Promise<IChatModelInformation> {
 		const modelInfo = await super.getModelInfo(modelId, apiKey, modelCapabilities);
-		const enableResponsesApi = this._configurationService.getExperimentBasedConfig(ConfigKey.UseResponsesApi, this._expService);
-		if (enableResponsesApi) {
-			modelInfo.supported_endpoints = [
-				ModelSupportedEndpoint.ChatCompletions,
-				ModelSupportedEndpoint.Responses
-			];
-		}
+		modelInfo.supported_endpoints = [
+			ModelSupportedEndpoint.ChatCompletions,
+			ModelSupportedEndpoint.Responses
+		];
 
 		return modelInfo;
 	}
diff --git a/extensions/copilot/src/platform/endpoint/node/chatEndpoint.ts b/extensions/copilot/src/platform/endpoint/node/chatEndpoint.ts
index ed002247f22..7b6826ca4bb 100644
--- a/extensions/copilot/src/platform/endpoint/node/chatEndpoint.ts
+++ b/extensions/copilot/src/platform/endpoint/node/chatEndpoint.ts
@@ -196,8 +196,7 @@ export class ChatEndpoint implements IChatEndpoint {
 			return true;
 		}
 
-		const enableResponsesApi = this._configurationService.getExperimentBasedConfig(ConfigKey.UseResponsesApi, this._expService);
-		return !!(enableResponsesApi && this.modelMetadata.supported_endpoints?.includes(ModelSupportedEndpoint.Responses));
+		return !!this.modelMetadata.supported_endpoints?.includes(ModelSupportedEndpoint.Responses);
 	}
 
 	protected get useMessagesApi(): boolean {
diff --git a/extensions/copilot/src/platform/endpoint/test/node/openaiCompatibleEndpoint.ts b/extensions/copilot/src/platform/endpoint/test/node/openaiCompatibleEndpoint.ts
index 5109b64067e..54ff3aa68a0 100644
--- a/extensions/copilot/src/platform/endpoint/test/node/openaiCompatibleEndpoint.ts
+++ b/extensions/copilot/src/platform/endpoint/test/node/openaiCompatibleEndpoint.ts
@@ -8,7 +8,7 @@ import { TokenizerType } from '../../../../util/common/tokenizer';
 import { IInstantiationService } from '../../../../util/vs/platform/instantiation/common/instantiation';
 import { IAuthenticationService } from '../../../authentication/common/authentication';
 import { IChatMLFetcher } from '../../../chat/common/chatMLFetcher';
-import { ConfigKey, IConfigurationService } from '../../../configuration/common/configurationService';
+import { IConfigurationService } from '../../../configuration/common/configurationService';
 import { IEnvService } from '../../../env/common/envService';
 import { ILogService } from '../../../log/common/logService';
 import { isOpenAiFunctionTool } from '../../../networking/common/fetch';
@@ -119,10 +119,6 @@ export class OpenAICompatibleTestEndpoint extends ChatEndpoint {
 				? modelConfig.supported_endpoints
 				: [ModelSupportedEndpoint.ChatCompletions]
 		};
-		// configurationService.useResponsesApi should be set to true if ModelSupportedEndpoint.Responses is in modelConfig.supported_endpoints
-		if (modelInfo.supported_endpoints?.includes(ModelSupportedEndpoint.Responses)) {
-			configurationService.setConfig(ConfigKey.UseResponsesApi, true);
-		}
 
 		super(
 			modelInfo,