feat: enhance strict compatibility for OpenAI requests

- Implement sanitization for `tool_choice` and removal of `disable_parallel_tool_use` in request payloads.
- Introduce logging for tool choice changes in `DoRequestHelper`.
- Update `ConvertRequest` to handle tool-call compatibility and maintain structured tool history.
- Add `ThoughtSignature` to `Part` struct for better tracking of reasoning content.
- Refactor request handling in `getRequestBody` to ensure strict compliance with OpenAI API requirements.

relay/adaptor/common.go

@@ -1,10 +1,13 @@
 package adaptor
 
 import (
+	"bytes"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"github.com/gin-gonic/gin"
 	"github.com/songquanpeng/one-api/common/client"
+	"github.com/songquanpeng/one-api/common/logger"
 	"github.com/songquanpeng/one-api/relay/meta"
 	"io"
 	"net/http"
@@ -24,6 +27,29 @@ func DoRequestHelper(a Adaptor, c *gin.Context, meta *meta.Meta, requestBody io.
 		return nil, fmt.Errorf("get request url failed: %w", err)
 	}
 
+	if requestBody != nil {
+		raw, readErr := io.ReadAll(requestBody)
+		if readErr != nil {
+			return nil, fmt.Errorf("read request body failed: %w", readErr)
+		}
+		hasDisableParallelBefore := bytes.Contains(raw, []byte("disable_parallel_tool_use"))
+		beforeToolChoice := extractToolChoiceForLog(raw)
+		raw = sanitizeStrictToolChoicePayload(raw)
+		hasDisableParallelAfter := bytes.Contains(raw, []byte("disable_parallel_tool_use"))
+		afterToolChoice := extractToolChoiceForLog(raw)
+		logger.Infof(
+			c.Request.Context(),
+			"[DoRequestHelper] outbound %s %s tool_choice(before=%s, after=%s) disable_parallel(before=%t, after=%t)",
+			c.Request.Method,
+			c.Request.URL.Path,
+			beforeToolChoice,
+			afterToolChoice,
+			hasDisableParallelBefore,
+			hasDisableParallelAfter,
+		)
+		requestBody = bytes.NewBuffer(raw)
+	}
+
 	req, err := http.NewRequest(c.Request.Method, fullRequestURL, requestBody)
 	if err != nil {
 		return nil, fmt.Errorf("new request failed: %w", err)
@@ -51,3 +77,80 @@ func DoRequest(c *gin.Context, req *http.Request) (*http.Response, error) {
 	_ = c.Request.Body.Close()
 	return resp, nil
 }
+
+// Global outbound guard for strict OpenAI-compatible gateways:
+// remove disable_parallel_tool_use recursively and normalize object tool_choice.
+func sanitizeStrictToolChoicePayload(data []byte) []byte {
+	var payload any
+	if err := json.Unmarshal(data, &payload); err != nil {
+		return data
+	}
+	root, ok := payload.(map[string]any)
+	if !ok {
+		return data
+	}
+	root = stripDisableParallelKeyAny(root).(map[string]any)
+
+	hasTools := false
+	if tools, ok := root["tools"].([]any); ok && len(tools) > 0 {
+		hasTools = true
+	}
+	if functions, ok := root["functions"]; ok && functions != nil {
+		hasTools = true
+	}
+	if tc, ok := root["tool_choice"]; ok {
+		switch tc.(type) {
+		case map[string]any, []any:
+			if hasTools {
+				root["tool_choice"] = "auto"
+			} else {
+				delete(root, "tool_choice")
+			}
+		}
+	}
+
+	out, err := json.Marshal(root)
+	if err != nil {
+		return data
+	}
+	return out
+}
+
+func stripDisableParallelKeyAny(v any) any {
+	switch val := v.(type) {
+	case map[string]any:
+		delete(val, "disable_parallel_tool_use")
+		for k, child := range val {
+			val[k] = stripDisableParallelKeyAny(child)
+		}
+		return val
+	case []any:
+		for i, child := range val {
+			val[i] = stripDisableParallelKeyAny(child)
+		}
+		return val
+	default:
+		return v
+	}
+}
+
+func extractToolChoiceForLog(data []byte) string {
+	var payload map[string]any
+	if err := json.Unmarshal(data, &payload); err != nil {
+		return "<invalid-json>"
+	}
+	tc, ok := payload["tool_choice"]
+	if !ok {
+		return "<absent>"
+	}
+	switch v := tc.(type) {
+	case string:
+		return v
+	default:
+		out, err := json.Marshal(v)
+		if err != nil {
+			return "<unmarshalable>"
+		}
+		return string(out)
+	}
+}

relay/adaptor/gemini/main.go

@@ -59,6 +59,7 @@ func sanitizeSchema(v interface{}) interface{} {
 
 // Setting safety to the lowest possible values since Gemini is already powerless enough
 func ConvertRequest(textRequest model.GeneralOpenAIRequest) *ChatRequest {
+	messagesForConvert := textRequest.Messages
 	geminiRequest := ChatRequest{
 		Contents: make([]ChatContent, 0, len(textRequest.Messages)),
 		SafetySettings: []ChatSafetySettings{
@@ -104,11 +105,6 @@ func ConvertRequest(textRequest model.GeneralOpenAIRequest) *ChatRequest {
 		geminiRequest.GenerationConfig.ResponseModalities = []string{"TEXT", "IMAGE"}
 	}
 
-	// Enable thinking when the client explicitly requests it via enable_thinking=true.
-	// Use thinkingBudget=-1 (dynamic) so Gemini decides the appropriate budget.
-	if textRequest.EnableThinking {
-		geminiRequest.GenerationConfig.ThinkingConfig = &GeminiThinkingConfig{ThinkingBudget: -1}
-	}
 	if textRequest.Tools != nil {
 		functions := make([]model.Function, 0, len(textRequest.Tools))
 		for _, tool := range textRequest.Tools {
@@ -130,42 +126,87 @@ func ConvertRequest(textRequest model.GeneralOpenAIRequest) *ChatRequest {
 			},
 		}
 	}
+
+	// Tool-call compatibility mode:
+	// Keep tool rounds on strict structured functionCall/functionResponse flow.
+	// Gemini thinking tool rounds behind gateways are prone to thought_signature
+	// validation failures; disable thinking config for tool flow to avoid fallback
+	// text replay and preserve structured tool history.
+	hasToolFlow := len(geminiRequest.Tools) > 0
+	if !hasToolFlow {
+		for _, msg := range messagesForConvert {
+			if msg.Role == "assistant" && len(msg.ToolCalls) > 0 {
+				hasToolFlow = true
+				break
+			}
+		}
+	}
+	if hasToolFlow {
+		// Remove incompatible historical tool-call turns that cannot satisfy
+		// Gemini thought_signature requirements. Keep structured tool flow for
+		// the remaining valid turns (no text downgrade replay).
+		messagesForConvert = sanitizeGeminiToolHistoryMessages(messagesForConvert)
+	}
+	// Enable thinking only for non-tool turns.
+	if textRequest.EnableThinking && !hasToolFlow {
+		// Use thinkingBudget=-1 (dynamic) so Gemini decides the appropriate budget.
+		geminiRequest.GenerationConfig.ThinkingConfig = &GeminiThinkingConfig{ThinkingBudget: -1}
+	} else if hasToolFlow {
+		geminiRequest.GenerationConfig.ThinkingConfig = nil
+	}
 	// Build a map from tool_call_id → function name for resolving tool result names
 	toolCallIdToName := map[string]string{}
-	for _, message := range textRequest.Messages {
+	lastKnownThoughtSignature := ""
+	for _, message := range messagesForConvert {
+		if message.ReasoningEncryptedContent != "" {
+			lastKnownThoughtSignature = message.ReasoningEncryptedContent
+		}
 		if message.Role == "assistant" {
 			for _, tc := range message.ToolCalls {
 				if tc.Id != "" && tc.Function.Name != "" {
 					toolCallIdToName[tc.Id] = tc.Function.Name
 				}
+				if tc.ExtraContent != nil && tc.ExtraContent.Google != nil && tc.ExtraContent.Google.ThoughtSignature != "" {
+					lastKnownThoughtSignature = tc.ExtraContent.Google.ThoughtSignature
+				}
 			}
 		}
 	}
 
 	shouldAddDummyModelMessage := false
-	for _, message := range textRequest.Messages {
+	for i := 0; i < len(messagesForConvert); i++ {
+		message := messagesForConvert[i]
 		// --- tool result: role=tool → Gemini functionResponse (user role) ---
+		// Gemini requires functionResponse parts to match functionCall parts from the
+		// preceding model turn. For OpenAI-compat payloads with multiple consecutive
+		// role=tool messages, merge them into a single user turn with multiple parts.
 		if message.Role == "tool" {
-			toolName := message.ToolCallId
-			if name, ok := toolCallIdToName[message.ToolCallId]; ok {
+			var responseParts []Part
+			for ; i < len(messagesForConvert) && messagesForConvert[i].Role == "tool"; i++ {
+				toolMessage := messagesForConvert[i]
+				toolName := toolMessage.ToolCallId
+				if name, ok := toolCallIdToName[toolMessage.ToolCallId]; ok {
 					toolName = name
-			} else if message.Name != nil && *message.Name != "" {
-				toolName = *message.Name
+				} else if toolMessage.Name != nil && *toolMessage.Name != "" {
+					toolName = *toolMessage.Name
 				}
 				if toolName == "" {
 					toolName = "unknown_tool"
 				}
-			geminiRequest.Contents = append(geminiRequest.Contents, ChatContent{
-				Role: "user",
-				Parts: []Part{
-					{
+				responseParts = append(responseParts, Part{
 					FunctionResponse: &FunctionResponse{
 						Name:     toolName,
-							Response: map[string]any{"content": message.StringContent()},
-						},
-					},
+						Response: map[string]any{"content": toolMessage.StringContent()},
 					},
 				})
+			}
+			if len(responseParts) > 0 {
+				geminiRequest.Contents = append(geminiRequest.Contents, ChatContent{
+					Role:  "user",
+					Parts: responseParts,
+				})
+			}
+			i--
 			continue
 		}
 
@@ -248,11 +289,25 @@ func ConvertRequest(textRequest model.GeneralOpenAIRequest) *ChatRequest {
 				} else {
 					args = map[string]any{}
 				}
+				thoughtSignature := ""
+				if tc.ExtraContent != nil && tc.ExtraContent.Google != nil {
+					thoughtSignature = tc.ExtraContent.Google.ThoughtSignature
+				}
+				if thoughtSignature == "" {
+					thoughtSignature = message.ReasoningEncryptedContent
+				}
+				if thoughtSignature == "" {
+					thoughtSignature = lastKnownThoughtSignature
+				}
+				if thoughtSignature != "" {
+					lastKnownThoughtSignature = thoughtSignature
+				}
 				fcParts = append(fcParts, Part{
 					FunctionCall: &FunctionCall{
 						FunctionName: tc.Function.Name,
 						Arguments:    args,
 					},
+					ThoughtSignature: thoughtSignature,
 				})
 			}
 			content.Role = "model"
@@ -298,6 +353,76 @@ func ConvertRequest(textRequest model.GeneralOpenAIRequest) *ChatRequest {
 	return &geminiRequest
 }
 
+func sanitizeGeminiToolHistoryMessages(messages []model.Message) []model.Message {
+	if len(messages) == 0 {
+		return messages
+	}
+	sanitized := make([]model.Message, 0, len(messages))
+	droppedToolCallIDs := make(map[string]struct{})
+	lastKnownThoughtSignature := ""
+
+	for _, message := range messages {
+		if message.ReasoningEncryptedContent != "" {
+			lastKnownThoughtSignature = message.ReasoningEncryptedContent
+		}
+
+		if message.Role == "assistant" && len(message.ToolCalls) > 0 {
+			keptToolCalls := make([]model.Tool, 0, len(message.ToolCalls))
+			for _, tc := range message.ToolCalls {
+				thoughtSignature := ""
+				if tc.ExtraContent != nil && tc.ExtraContent.Google != nil {
+					thoughtSignature = strings.TrimSpace(tc.ExtraContent.Google.ThoughtSignature)
+				}
+				if thoughtSignature == "" {
+					thoughtSignature = strings.TrimSpace(message.ReasoningEncryptedContent)
+				}
+				if thoughtSignature == "" {
+					thoughtSignature = strings.TrimSpace(lastKnownThoughtSignature)
+				}
+				if thoughtSignature == "" {
+					if tc.Id != "" {
+						droppedToolCallIDs[tc.Id] = struct{}{}
+					}
+					continue
+				}
+
+				if tc.ExtraContent == nil {
+					tc.ExtraContent = &model.ToolExtraContent{}
+				}
+				if tc.ExtraContent.Google == nil {
+					tc.ExtraContent.Google = &model.GoogleToolExtraContent{}
+				}
+				tc.ExtraContent.Google.ThoughtSignature = thoughtSignature
+				lastKnownThoughtSignature = thoughtSignature
+				keptToolCalls = append(keptToolCalls, tc)
+			}
+
+			if len(keptToolCalls) == 0 {
+				assistantText := strings.TrimSpace(message.StringContent())
+				if assistantText == "" {
+					continue
+				}
+				message.ToolCalls = nil
+				message.Content = assistantText
+				sanitized = append(sanitized, message)
+				continue
+			}
+			message.ToolCalls = keptToolCalls
+			sanitized = append(sanitized, message)
+			continue
+		}
+
+		if message.Role == "tool" && message.ToolCallId != "" {
+			if _, dropped := droppedToolCallIDs[message.ToolCallId]; dropped {
+				continue
+			}
+		}
+		sanitized = append(sanitized, message)
+	}
+
+	return sanitized
+}
+
 func ConvertEmbeddingRequest(request model.GeneralOpenAIRequest) *BatchEmbeddingRequest {
 	inputs := request.ParseInput()
 	requests := make([]EmbeddingRequest, len(inputs))
@@ -369,15 +494,14 @@ type ChatPromptFeedback struct {
 
 func getToolCalls(candidate *ChatCandidate) []model.Tool {
 	var toolCalls []model.Tool
-
-	item := candidate.Content.Parts[0]
+	for _, item := range candidate.Content.Parts {
 		if item.FunctionCall == nil {
-		return toolCalls
+			continue
 		}
 		argsBytes, err := json.Marshal(item.FunctionCall.Arguments)
 		if err != nil {
 			logger.FatalLog("getToolCalls failed: " + err.Error())
-		return toolCalls
+			continue
 		}
 		toolCall := model.Tool{
 			Id:   fmt.Sprintf("call_%s", random.GetUUID()),
@@ -387,7 +511,15 @@ func getToolCalls(candidate *ChatCandidate) []model.Tool {
 				Name:      item.FunctionCall.FunctionName,
 			},
 		}
+		if item.ThoughtSignature != "" {
+			toolCall.ExtraContent = &model.ToolExtraContent{
+				Google: &model.GoogleToolExtraContent{
+					ThoughtSignature: item.ThoughtSignature,
+				},
+			}
+		}
 		toolCalls = append(toolCalls, toolCall)
+	}
 	return toolCalls
 }
 
@@ -407,12 +539,13 @@ func responseGeminiChat2OpenAI(response *ChatResponse) *openai.TextResponse {
 			FinishReason: constant.StopFinishReason,
 		}
 		if len(candidate.Content.Parts) > 0 {
-			if candidate.Content.Parts[0].FunctionCall != nil {
-				choice.Message.ToolCalls = getToolCalls(&candidate)
+			toolCalls := getToolCalls(&candidate)
+			if len(toolCalls) > 0 {
+				choice.Message.ToolCalls = toolCalls
 			} else {
 				var builder strings.Builder
-				for _, part := range candidate.Content.Parts {
-					if i > 0 {
+				for j, part := range candidate.Content.Parts {
+					if j > 0 {
 						builder.WriteString("\n")
 					}
 					builder.WriteString(part.Text)
@@ -434,10 +567,35 @@ func streamResponseGeminiChat2OpenAI(geminiResponse *ChatResponse) *openai.ChatC
 	if len(geminiResponse.Candidates) > 0 {
 		var textBuilder strings.Builder
 		var thinkingBuilder strings.Builder
+		var toolCalls []model.Tool
 		for _, part := range geminiResponse.Candidates[0].Content.Parts {
 			if part.Thought {
 				// Thinking/reasoning content — route to reasoning_content field
 				thinkingBuilder.WriteString(part.Text)
+			} else if part.FunctionCall != nil {
+				argsBytes, err := json.Marshal(part.FunctionCall.Arguments)
+				if err != nil {
+					logger.FatalLog("streamResponseGeminiChat2OpenAI marshal args failed: " + err.Error())
+					argsBytes = []byte("{}")
+				}
+				toolCalls = append(toolCalls, model.Tool{
+					Id:   fmt.Sprintf("call_%s", random.GetUUID()),
+					Type: "function",
+					Function: model.Function{
+						Name:      part.FunctionCall.FunctionName,
+						Arguments: string(argsBytes),
+					},
+					ExtraContent: func() *model.ToolExtraContent {
+						if part.ThoughtSignature == "" {
+							return nil
+						}
+						return &model.ToolExtraContent{
+							Google: &model.GoogleToolExtraContent{
+								ThoughtSignature: part.ThoughtSignature,
+							},
+						}
+					}(),
+				})
 			} else if part.Text != "" {
 				textBuilder.WriteString(part.Text)
 			} else if part.InlineData != nil && part.InlineData.Data != "" {
@@ -455,6 +613,11 @@ func streamResponseGeminiChat2OpenAI(geminiResponse *ChatResponse) *openai.ChatC
 		if thinkingBuilder.Len() > 0 {
 			choice.Delta.ReasoningContent = thinkingBuilder.String()
 		}
+		if len(toolCalls) > 0 {
+			choice.Delta.ToolCalls = toolCalls
+			toolFinish := "tool_calls"
+			choice.FinishReason = &toolFinish
+		}
 	}
 
 	var response openai.ChatCompletionsStreamResponse

relay/adaptor/gemini/model.go

@@ -55,6 +55,7 @@ type Part struct {
 	InlineData       *InlineData       `json:"inlineData,omitempty"`
 	FunctionCall     *FunctionCall     `json:"functionCall,omitempty"`
 	FunctionResponse *FunctionResponse `json:"functionResponse,omitempty"`
+	ThoughtSignature string            `json:"thoughtSignature,omitempty"`
 	// Thought marks this part as internal reasoning/thinking content (Gemini thinking models)
 	Thought bool `json:"thought,omitempty"`
 }

relay/controller/helper.go

@@ -32,6 +32,8 @@ func getAndValidateTextRequest(c *gin.Context, relayMode int) (*relaymodel.Gener
 	if err != nil {
 		return nil, err
 	}
+	sanitized := sanitizeToolChoiceForStrictCompat(textRequest)
+	c.Set("sanitized_text_request_modified", sanitized)
 	if relayMode == relaymode.Moderations && textRequest.Model == "" {
 		textRequest.Model = "text-moderation-latest"
 	}
@@ -45,6 +47,62 @@ func getAndValidateTextRequest(c *gin.Context, relayMode int) (*relaymodel.Gener
 	return textRequest, nil
 }
 
+func sanitizeToolChoiceForStrictCompat(req *relaymodel.GeneralOpenAIRequest) bool {
+	if req == nil {
+		return false
+	}
+	modified := stripDisableParallelToolUse(&req.ToolChoice)
+	// Strict OpenAI-compatible gateways often reject object-form tool_choice.
+	// Coerce object/array forms to "auto" when tools/functions exist.
+	switch req.ToolChoice.(type) {
+	case map[string]any, []any:
+		if len(req.Tools) > 0 || req.Functions != nil {
+			if req.ToolChoice != "auto" {
+				modified = true
+			}
+			req.ToolChoice = "auto"
+		} else {
+			if req.ToolChoice != nil {
+				modified = true
+			}
+			req.ToolChoice = nil
+		}
+	}
+	return modified
+}
+
+func stripDisableParallelToolUse(v *any) bool {
+	if v == nil || *v == nil {
+		return false
+	}
+	modified := false
+	switch val := (*v).(type) {
+	case map[string]any:
+		if _, ok := val["disable_parallel_tool_use"]; ok {
+			delete(val, "disable_parallel_tool_use")
+			modified = true
+		}
+		for k := range val {
+			child := val[k]
+			if stripDisableParallelToolUse(&child) {
+				modified = true
+			}
+			val[k] = child
+		}
+		*v = val
+	case []any:
+		for i := range val {
+			child := val[i]
+			if stripDisableParallelToolUse(&child) {
+				modified = true
+			}
+			val[i] = child
+		}
+		*v = val
+	}
+	return modified
+}
+
 func getPromptTokens(textRequest *relaymodel.GeneralOpenAIRequest, relayMode int) int {
 	switch relayMode {
 	case relaymode.ChatCompletions:

relay/controller/proxy.go

@@ -2,7 +2,9 @@
 package controller
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
@@ -24,7 +26,14 @@ func RelayProxyHelper(c *gin.Context, relayMode int) *relaymodel.ErrorWithStatus
 	}
 	adaptor.Init(meta)
 
-	resp, err := adaptor.DoRequest(c, meta, c.Request.Body)
+	requestBody, err := io.ReadAll(c.Request.Body)
+	if err != nil {
+		logger.Errorf(ctx, "read proxy request body failed: %s", err.Error())
+		return openai.ErrorWrapper(err, "read_request_body_failed", http.StatusBadRequest)
+	}
+	requestBody = sanitizeStrictToolChoiceJSON(requestBody)
+
+	resp, err := adaptor.DoRequest(c, meta, bytes.NewBuffer(requestBody))
 	if err != nil {
 		logger.Errorf(ctx, "DoRequest failed: %s", err.Error())
 		return openai.ErrorWrapper(err, "do_request_failed", http.StatusInternalServerError)

relay/controller/text.go

@@ -9,15 +9,12 @@ import (
 
 	"github.com/gin-gonic/gin"
 
-	"github.com/songquanpeng/one-api/common/config"
 	"github.com/songquanpeng/one-api/common/logger"
 	"github.com/songquanpeng/one-api/relay"
 	"github.com/songquanpeng/one-api/relay/adaptor"
 	"github.com/songquanpeng/one-api/relay/adaptor/openai"
-	"github.com/songquanpeng/one-api/relay/apitype"
 	"github.com/songquanpeng/one-api/relay/billing"
 	billingratio "github.com/songquanpeng/one-api/relay/billing/ratio"
-	"github.com/songquanpeng/one-api/relay/channeltype"
 	"github.com/songquanpeng/one-api/relay/meta"
 	"github.com/songquanpeng/one-api/relay/model"
 )
@@ -98,14 +95,9 @@ func RelayTextHelper(c *gin.Context) *model.ErrorWithStatusCode {
 }
 
 func getRequestBody(c *gin.Context, meta *meta.Meta, textRequest *model.GeneralOpenAIRequest, adaptor adaptor.Adaptor) (io.Reader, error) {
-	if !config.EnforceIncludeUsage &&
-		meta.APIType == apitype.OpenAI &&
-		meta.OriginModelName == meta.ActualModelName &&
-		meta.ChannelType != channeltype.Baichuan &&
-		meta.ForcedSystemPrompt == "" {
-		// no need to convert request for openai
-		return c.Request.Body, nil
-	}
+	// Always convert request through adaptor before sending upstream.
+	// This avoids passthrough edge cases where strict-compat sanitization may be bypassed.
+	// The slight performance cost is acceptable compared to malformed request risk.
 
 	// get request body
 	var requestBody io.Reader
@@ -119,7 +111,72 @@ func getRequestBody(c *gin.Context, meta *meta.Meta, textRequest *model.GeneralO
 		logger.Debugf(c.Request.Context(), "converted request json_marshal_failed: %s\n", err.Error())
 		return nil, err
 	}
+	jsonData = sanitizeStrictToolChoiceJSON(jsonData)
 	logger.Debugf(c.Request.Context(), "converted request: \n%s", string(jsonData))
 	requestBody = bytes.NewBuffer(jsonData)
 	return requestBody, nil
 }
+
+// Final outbound guard for strict OpenAI-compatible gateways:
+// - remove any disable_parallel_tool_use key at any depth
+// - coerce object/array tool_choice to OpenAI-compatible string form
+func sanitizeStrictToolChoiceJSON(data []byte) []byte {
+	var payload any
+	if err := json.Unmarshal(data, &payload); err != nil {
+		return data
+	}
+
+	root, ok := payload.(map[string]any)
+	if !ok {
+		return data
+	}
+
+	cleaned := stripDisableParallelToolUseAny(root)
+	root, ok = cleaned.(map[string]any)
+	if !ok {
+		return data
+	}
+
+	hasTools := false
+	if tools, ok := root["tools"].([]any); ok && len(tools) > 0 {
+		hasTools = true
+	}
+	if functions, ok := root["functions"]; ok && functions != nil {
+		hasTools = true
+	}
+
+	if tc, ok := root["tool_choice"]; ok {
+		switch tc.(type) {
+		case map[string]any, []any:
+			if hasTools {
+				root["tool_choice"] = "auto"
+			} else {
+				delete(root, "tool_choice")
+			}
+		}
+	}
+
+	out, err := json.Marshal(root)
+	if err != nil {
+		return data
+	}
+	return out
+}
+
+func stripDisableParallelToolUseAny(v any) any {
+	switch val := v.(type) {
+	case map[string]any:
+		delete(val, "disable_parallel_tool_use")
+		for k, child := range val {
+			val[k] = stripDisableParallelToolUseAny(child)
+		}
+		return val
+	case []any:
+		for i, child := range val {
+			val[i] = stripDisableParallelToolUseAny(child)
+		}
+		return val
+	default:
+		return v
+	}
+}

relay/model/message.go

@@ -4,6 +4,7 @@ type Message struct {
 	Role             string  `json:"role,omitempty"`
 	Content          any     `json:"content,omitempty"`
 	ReasoningContent any     `json:"reasoning_content,omitempty"`
+	ReasoningEncryptedContent string `json:"reasoning_encrypted_content,omitempty"`
 	Name             *string `json:"name,omitempty"`
 	ToolCalls        []Tool  `json:"tool_calls,omitempty"`
 	ToolCallId       string  `json:"tool_call_id,omitempty"`

relay/model/tool.go

@@ -4,6 +4,7 @@ type Tool struct {
 	Id           string           `json:"id,omitempty"`
 	Type         string           `json:"type,omitempty"` // when splicing claude tools stream messages, it is empty
 	Function     Function         `json:"function"`
+	ExtraContent *ToolExtraContent `json:"extra_content,omitempty"`
 }
 
 type Function struct {
@@ -12,3 +13,11 @@ type Function struct {
 	Parameters  any    `json:"parameters,omitempty"` // request
 	Arguments   any    `json:"arguments,omitempty"`  // response
 }
+
+type ToolExtraContent struct {
+	Google *GoogleToolExtraContent `json:"google,omitempty"`
+}
+
+type GoogleToolExtraContent struct {
+	ThoughtSignature string `json:"thought_signature,omitempty"`
+}