From 1b56f5ef8440f0e36ca8582dfa70d6a469c3cba7 Mon Sep 17 00:00:00 2001
From: Roo Code <roomote@roocode.com>
Date: Tue, 13 Jan 2026 22:19:19 +0000
Subject: [PATCH] feat: add openAiOmitToolChoice setting for Azure/LiteLLM
 compatibility

Add a new boolean setting that allows users to omit the tool_choice
parameter from OpenAI API requests. This fixes compatibility issues
with Azure-hosted models and LiteLLM proxies that do not support
the tool_choice parameter.

Fixes #10701
---
 packages/types/src/provider-settings.ts              |  1 +
 src/api/providers/openai.ts                          | 12 ++++++++----
 .../settings/providers/OpenAICompatible.tsx          | 10 ++++++++++
 webview-ui/src/i18n/locales/en/settings.json         |  2 ++
 4 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/packages/types/src/provider-settings.ts b/packages/types/src/provider-settings.ts
index d5880cd3b13..3f39ad0eccd 100644
--- a/packages/types/src/provider-settings.ts
+++ b/packages/types/src/provider-settings.ts
@@ -250,6 +250,7 @@ const openAiSchema = baseProviderSettingsSchema.extend({
 	openAiStreamingEnabled: z.boolean().optional(),
 	openAiHostHeader: z.string().optional(), // Keep temporarily for backward compatibility during migration.
 	openAiHeaders: z.record(z.string(), z.string()).optional(),
+	openAiOmitToolChoice: z.boolean().optional(), // Omit tool_choice parameter for Azure/LiteLLM compatibility.
 })
 
 const ollamaSchema = baseProviderSettingsSchema.extend({
diff --git a/src/api/providers/openai.ts b/src/api/providers/openai.ts
index 9d632fbdf4c..918bc52a6c8 100644
--- a/src/api/providers/openai.ts
+++ b/src/api/providers/openai.ts
@@ -161,7 +161,8 @@ export class OpenAiHandler extends BaseProvider implements SingleCompletionHandl
 				...(isGrokXAI ? {} : { stream_options: { include_usage: true } }),
 				...(reasoning && reasoning),
 				...(metadata?.tools && { tools: this.convertToolsForOpenAI(metadata.tools) }),
-				...(metadata?.tool_choice && { tool_choice: metadata.tool_choice }),
+				...(metadata?.tool_choice &&
+					!this.options.openAiOmitToolChoice && { tool_choice: metadata.tool_choice }),
 				...(metadata?.toolProtocol === "native" &&
 					metadata.parallelToolCalls === true && {
 						parallel_tool_calls: true,
@@ -231,7 +232,8 @@ export class OpenAiHandler extends BaseProvider implements SingleCompletionHandl
 					? convertToR1Format([{ role: "user", content: systemPrompt }, ...messages])
 					: [systemMessage, ...convertToOpenAiMessages(messages)],
 				...(metadata?.tools && { tools: this.convertToolsForOpenAI(metadata.tools) }),
-				...(metadata?.tool_choice && { tool_choice: metadata.tool_choice }),
+				...(metadata?.tool_choice &&
+					!this.options.openAiOmitToolChoice && { tool_choice: metadata.tool_choice }),
 				...(metadata?.toolProtocol === "native" &&
 					metadata.parallelToolCalls === true && {
 						parallel_tool_calls: true,
@@ -358,7 +360,8 @@ export class OpenAiHandler extends BaseProvider implements SingleCompletionHandl
 				reasoning_effort: modelInfo.reasoningEffort as "low" | "medium" | "high" | undefined,
 				temperature: undefined,
 				...(metadata?.tools && { tools: this.convertToolsForOpenAI(metadata.tools) }),
-				...(metadata?.tool_choice && { tool_choice: metadata.tool_choice }),
+				...(metadata?.tool_choice &&
+					!this.options.openAiOmitToolChoice && { tool_choice: metadata.tool_choice }),
 				...(metadata?.toolProtocol === "native" &&
 					metadata.parallelToolCalls === true && {
 						parallel_tool_calls: true,
@@ -394,7 +397,8 @@ export class OpenAiHandler extends BaseProvider implements SingleCompletionHandl
 				reasoning_effort: modelInfo.reasoningEffort as "low" | "medium" | "high" | undefined,
 				temperature: undefined,
 				...(metadata?.tools && { tools: this.convertToolsForOpenAI(metadata.tools) }),
-				...(metadata?.tool_choice && { tool_choice: metadata.tool_choice }),
+				...(metadata?.tool_choice &&
+					!this.options.openAiOmitToolChoice && { tool_choice: metadata.tool_choice }),
 				...(metadata?.toolProtocol === "native" &&
 					metadata.parallelToolCalls === true && {
 						parallel_tool_calls: true,
diff --git a/webview-ui/src/components/settings/providers/OpenAICompatible.tsx b/webview-ui/src/components/settings/providers/OpenAICompatible.tsx
index 4eea6f09f1b..393df0e536b 100644
--- a/webview-ui/src/components/settings/providers/OpenAICompatible.tsx
+++ b/webview-ui/src/components/settings/providers/OpenAICompatible.tsx
@@ -173,6 +173,16 @@ export const OpenAICompatible = ({
 				onChange={handleInputChange("openAiUseAzure", noTransform)}>
 				{t("settings:modelInfo.useAzure")}
 			</Checkbox>
+			<div>
+				<Checkbox
+					checked={apiConfiguration?.openAiOmitToolChoice ?? false}
+					onChange={handleInputChange("openAiOmitToolChoice", noTransform)}>
+					{t("settings:modelInfo.omitToolChoice")}
+				</Checkbox>
+				<div className="text-sm text-vscode-descriptionForeground ml-6">
+					{t("settings:modelInfo.omitToolChoiceDescription")}
+				</div>
+			</div>
 			<div>
 				<Checkbox
 					checked={azureApiVersionSelected}
diff --git a/webview-ui/src/i18n/locales/en/settings.json b/webview-ui/src/i18n/locales/en/settings.json
index fc64ad18510..0ec646b0eb5 100644
--- a/webview-ui/src/i18n/locales/en/settings.json
+++ b/webview-ui/src/i18n/locales/en/settings.json
@@ -879,6 +879,8 @@
 		"enableR1FormatTips": "Must be enabled when using R1 models such as QWQ to prevent 400 errors",
 		"useAzure": "Use Azure",
 		"azureApiVersion": "Set Azure API version",
+		"omitToolChoice": "Omit tool_choice parameter",
+		"omitToolChoiceDescription": "Enable this if your Azure or LiteLLM proxy does not support the tool_choice parameter.",
 		"gemini": {
 			"freeRequests": "* Free up to {{count}} requests per minute. After that, billing depends on prompt size.",
 			"pricingDetails": "For more info, see pricing details.",