Fix (race): mutex chatbody

2026-03-07 10:46:18 +03:00
parent 014e297ae3
commit a842b00e96
9 changed files with 422 additions and 142 deletions
--- a/bot.go
+++ b/bot.go
@@ -37,7 +37,7 @@ var (
 	chunkChan       = make(chan string, 10)
 	openAIToolChan  = make(chan string, 10)
 	streamDone      = make(chan bool, 1)
-	chatBody        *models.ChatBody
+	chatBody        *models.SafeChatBody
 	store           storage.FullRepo
 	defaultFirstMsg = "Hello! What can I do for you?"
 	defaultStarter  = []models.RoleMsg{}
@@ -262,13 +262,13 @@ func warmUpModel() {
 		return
 	}
 	// Check if model is already loaded
-	loaded, err := isModelLoaded(chatBody.Model)
+	loaded, err := isModelLoaded(chatBody.GetModel())
 	if err != nil {
-		logger.Debug("failed to check model status", "model", chatBody.Model, "error", err)
+		logger.Debug("failed to check model status", "model", chatBody.GetModel(), "error", err)
 		// Continue with warmup attempt anyway
 	}
 	if loaded {
-		showToast("model already loaded", "Model "+chatBody.Model+" is already loaded.")
+		showToast("model already loaded", "Model "+chatBody.GetModel()+" is already loaded.")
 		return
 	}
 	go func() {
@@ -277,7 +277,7 @@ func warmUpModel() {
 		switch {
 		case strings.HasSuffix(cfg.CurrentAPI, "/completion"):
 			// Old completion endpoint
-			req := models.NewLCPReq(".", chatBody.Model, nil, map[string]float32{
+			req := models.NewLCPReq(".", chatBody.GetModel(), nil, map[string]float32{
 				"temperature":    0.8,
 				"dry_multiplier": 0.0,
 				"min_p":          0.05,
@@ -289,7 +289,7 @@ func warmUpModel() {
 			// OpenAI-compatible chat endpoint
 			req := models.OpenAIReq{
 				ChatBody: &models.ChatBody{
-					Model: chatBody.Model,
+					Model: chatBody.GetModel(),
 					Messages: []models.RoleMsg{
 						{Role: "system", Content: "."},
 					},
@@ -313,7 +313,7 @@ func warmUpModel() {
 		}
 		resp.Body.Close()
 		// Start monitoring for model load completion
-		monitorModelLoad(chatBody.Model)
+		monitorModelLoad(chatBody.GetModel())
 	}()
 }

@@ -418,7 +418,9 @@ func fetchLCPModelsWithStatus() (*models.LCPModels, error) {
 	if err := json.NewDecoder(resp.Body).Decode(data); err != nil {
 		return nil, err
 	}
+	localModelsMu.Lock()
 	localModelsData = data
+	localModelsMu.Unlock()
 	return data, nil
 }

@@ -821,10 +823,10 @@ func chatRound(r *models.ChatRoundReq) error {
 	}
 	go sendMsgToLLM(reader)
 	logger.Debug("looking at vars in chatRound", "msg", r.UserMsg, "regen", r.Regen, "resume", r.Resume)
-	msgIdx := len(chatBody.Messages)
+	msgIdx := chatBody.GetMessageCount()
 	if !r.Resume {
 		// Add empty message to chatBody immediately so it persists during Alt+T toggle
-		chatBody.Messages = append(chatBody.Messages, models.RoleMsg{
+		chatBody.AppendMessage(models.RoleMsg{
 			Role: botPersona, Content: "",
 		})
 		nl := "\n\n"
@@ -836,7 +838,7 @@ func chatRound(r *models.ChatRoundReq) error {
 		}
 		fmt.Fprintf(textView, "%s[-:-:b](%d) %s[-:-:-]\n", nl, msgIdx, roleToIcon(botPersona))
 	} else {
-		msgIdx = len(chatBody.Messages) - 1
+		msgIdx = chatBody.GetMessageCount() - 1
 	}
 	respText := strings.Builder{}
 	toolResp := strings.Builder{}
@@ -893,7 +895,10 @@ out:
 			fmt.Fprint(textView, chunk)
 			respText.WriteString(chunk)
 			// Update the message in chatBody.Messages so it persists during Alt+T
-			chatBody.Messages[msgIdx].Content = respText.String()
+			chatBody.UpdateMessageFunc(msgIdx, func(msg models.RoleMsg) models.RoleMsg {
+				msg.Content = respText.String()
+				return msg
+			})
 			if scrollToEndEnabled {
 				textView.ScrollToEnd()
 			}
@@ -936,29 +941,32 @@ out:
 	}
 	botRespMode = false
 	if r.Resume {
-		chatBody.Messages[len(chatBody.Messages)-1].Content += respText.String()
-		updatedMsg := chatBody.Messages[len(chatBody.Messages)-1]
-		processedMsg := processMessageTag(&updatedMsg)
-		chatBody.Messages[len(chatBody.Messages)-1] = *processedMsg
-		if msgStats != nil && chatBody.Messages[len(chatBody.Messages)-1].Role != cfg.ToolRole {
-			chatBody.Messages[len(chatBody.Messages)-1].Stats = msgStats
+		chatBody.UpdateMessageFunc(chatBody.GetMessageCount()-1, func(msg models.RoleMsg) models.RoleMsg {
+			msg.Content += respText.String()
+			processedMsg := processMessageTag(&msg)
+			if msgStats != nil && processedMsg.Role != cfg.ToolRole {
+				processedMsg.Stats = msgStats
 			}
+			return *processedMsg
+		})
 	} else {
-		chatBody.Messages[msgIdx].Content = respText.String()
-		processedMsg := processMessageTag(&chatBody.Messages[msgIdx])
-		chatBody.Messages[msgIdx] = *processedMsg
-		if msgStats != nil && chatBody.Messages[msgIdx].Role != cfg.ToolRole {
-			chatBody.Messages[msgIdx].Stats = msgStats
+		chatBody.UpdateMessageFunc(msgIdx, func(msg models.RoleMsg) models.RoleMsg {
+			msg.Content = respText.String()
+			processedMsg := processMessageTag(&msg)
+			if msgStats != nil && processedMsg.Role != cfg.ToolRole {
+				processedMsg.Stats = msgStats
 			}
-		stopTTSIfNotForUser(&chatBody.Messages[msgIdx])
+			return *processedMsg
+		})
+		stopTTSIfNotForUser(&chatBody.GetMessages()[msgIdx])
 	}
 	cleanChatBody()
 	refreshChatDisplay()
 	updateStatusLine()
 	// bot msg is done;
 	// now check it for func call
-	// logChat(activeChatName, chatBody.Messages)
-	if err := updateStorageChat(activeChatName, chatBody.Messages); err != nil {
+	// logChat(activeChatName, chatBody.GetMessages())
+	if err := updateStorageChat(activeChatName, chatBody.GetMessages()); err != nil {
 		logger.Warn("failed to update storage", "error", err, "name", activeChatName)
 	}
 	// Strip think blocks before parsing for tool calls
@@ -973,8 +981,8 @@ out:
 	// If so, trigger those characters to respond if that char is not controlled by user
 	// perhaps we should have narrator role to determine which char is next to act
 	if cfg.AutoTurn {
-		lastMsg := chatBody.Messages[len(chatBody.Messages)-1]
-		if len(lastMsg.KnownTo) > 0 {
+		lastMsg, ok := chatBody.GetLastMessage()
+		if ok && len(lastMsg.KnownTo) > 0 {
 			triggerPrivateMessageResponses(&lastMsg)
 		}
 	}
@@ -983,13 +991,15 @@ out:

 // cleanChatBody removes messages with null or empty content to prevent API issues
 func cleanChatBody() {
-	if chatBody == nil || chatBody.Messages == nil {
+	if chatBody == nil || chatBody.GetMessageCount() == 0 {
 		return
 	}
 	// Tool request cleaning is now configurable via AutoCleanToolCallsFromCtx (default false)
 	// /completion msg where part meant for user and other part tool call
 	// chatBody.Messages = cleanToolCalls(chatBody.Messages)
-	chatBody.Messages = consolidateAssistantMessages(chatBody.Messages)
+	chatBody.WithLock(func(cb *models.ChatBody) {
+		cb.Messages = consolidateAssistantMessages(cb.Messages)
+	})
 }

 // convertJSONToMapStringString unmarshals JSON into map[string]interface{} and converts all values to strings.
@@ -1089,7 +1099,7 @@ func findCall(msg, toolCall string) bool {
 				Content:    fmt.Sprintf("Error processing tool call: %v. Please check the JSON format and try again.", err),
 				ToolCallID: lastToolCall.ID, // Use the stored tool call ID
 			}
-			chatBody.Messages = append(chatBody.Messages, toolResponseMsg)
+			chatBody.AppendMessage(toolResponseMsg)
 			// Clear the stored tool call ID after using it (no longer needed)
 			// Trigger the assistant to continue processing with the error message
 			crr := &models.ChatRoundReq{
@@ -1126,7 +1136,7 @@ func findCall(msg, toolCall string) bool {
 				Role:    cfg.ToolRole,
 				Content: "Error processing tool call: no valid JSON found. Please check the JSON format.",
 			}
-			chatBody.Messages = append(chatBody.Messages, toolResponseMsg)
+			chatBody.AppendMessage(toolResponseMsg)
 			crr := &models.ChatRoundReq{
 				Role: cfg.AssistantRole,
 			}
@@ -1143,8 +1153,8 @@ func findCall(msg, toolCall string) bool {
 				Role:    cfg.ToolRole,
 				Content: fmt.Sprintf("Error processing tool call: %v. Please check the JSON format and try again.", err),
 			}
-			chatBody.Messages = append(chatBody.Messages, toolResponseMsg)
-			logger.Debug("findCall: added tool error response", "role", toolResponseMsg.Role, "content_len", len(toolResponseMsg.Content), "message_count_after_add", len(chatBody.Messages))
+			chatBody.AppendMessage(toolResponseMsg)
+			logger.Debug("findCall: added tool error response", "role", toolResponseMsg.Role, "content_len", len(toolResponseMsg.Content), "message_count_after_add", chatBody.GetMessageCount())
 			// Trigger the assistant to continue processing with the error message
 			// chatRound("", cfg.AssistantRole, tv, false, false)
 			crr := &models.ChatRoundReq{
@@ -1162,17 +1172,23 @@ func findCall(msg, toolCall string) bool {
 	// we got here => last msg recognized as a tool call (correct or not)
 	// Use the tool call ID from streaming response (lastToolCall.ID)
 	// Don't generate random ID - the ID should match between assistant message and tool response
-	lastMsgIdx := len(chatBody.Messages) - 1
+	lastMsgIdx := chatBody.GetMessageCount() - 1
 	if lastToolCall.ID != "" {
-		chatBody.Messages[lastMsgIdx].ToolCallID = lastToolCall.ID
+		chatBody.UpdateMessageFunc(lastMsgIdx, func(msg models.RoleMsg) models.RoleMsg {
+			msg.ToolCallID = lastToolCall.ID
+			return msg
+		})
 	}
 	// Store tool call info in the assistant message
 	// Convert Args map to JSON string for storage
-	chatBody.Messages[lastMsgIdx].ToolCall = &models.ToolCall{
+	chatBody.UpdateMessageFunc(lastMsgIdx, func(msg models.RoleMsg) models.RoleMsg {
+		msg.ToolCall = &models.ToolCall{
 			ID:   lastToolCall.ID,
 			Name: lastToolCall.Name,
 			Args: mapToString(lastToolCall.Args),
 		}
+		return msg
+	})
 	// call a func
 	_, ok := fnMap[fc.Name]
 	if !ok {
@@ -1183,8 +1199,8 @@ func findCall(msg, toolCall string) bool {
 			Content:    m,
 			ToolCallID: lastToolCall.ID, // Use the stored tool call ID
 		}
-		chatBody.Messages = append(chatBody.Messages, toolResponseMsg)
-		logger.Debug("findCall: added tool not implemented response", "role", toolResponseMsg.Role, "content_len", len(toolResponseMsg.Content), "tool_call_id", toolResponseMsg.ToolCallID, "message_count_after_add", len(chatBody.Messages))
+		chatBody.AppendMessage(toolResponseMsg)
+		logger.Debug("findCall: added tool not implemented response", "role", toolResponseMsg.Role, "content_len", len(toolResponseMsg.Content), "tool_call_id", toolResponseMsg.ToolCallID, "message_count_after_add", chatBody.GetMessageCount())
 		// Clear the stored tool call ID after using it
 		lastToolCall.ID = ""
 		// Trigger the assistant to continue processing with the new tool response
@@ -1255,9 +1271,9 @@ func findCall(msg, toolCall string) bool {
 		}
 	}
 	fmt.Fprintf(textView, "%s[-:-:b](%d) <%s>: [-:-:-]\n%s\n",
-		"\n\n", len(chatBody.Messages), cfg.ToolRole, toolResponseMsg.GetText())
-	chatBody.Messages = append(chatBody.Messages, toolResponseMsg)
-	logger.Debug("findCall: added actual tool response", "role", toolResponseMsg.Role, "content_len", len(toolResponseMsg.Content), "tool_call_id", toolResponseMsg.ToolCallID, "message_count_after_add", len(chatBody.Messages))
+		"\n\n", chatBody.GetMessageCount(), cfg.ToolRole, toolResponseMsg.GetText())
+	chatBody.AppendMessage(toolResponseMsg)
+	logger.Debug("findCall: added actual tool response", "role", toolResponseMsg.Role, "content_len", len(toolResponseMsg.Content), "tool_call_id", toolResponseMsg.ToolCallID, "message_count_after_add", chatBody.GetMessageCount())
 	// Clear the stored tool call ID after using it
 	lastToolCall.ID = ""
 	// Trigger the assistant to continue processing with the new tool response
@@ -1497,7 +1513,7 @@ func init() {
 	// load cards
 	basicCard.Role = cfg.AssistantRole
 	logLevel.Set(slog.LevelInfo)
-	logger = slog.New(slog.NewTextHandler(logfile, &slog.HandlerOptions{Level: logLevel}))
+	logger = slog.New(slog.NewTextHandler(logfile, &slog.HandlerOptions{Level: logLevel, AddSource: true}))
 	store = storage.NewProviderSQL(cfg.DBPATH, logger)
 	if store == nil {
 		cancel()
@@ -1521,11 +1537,11 @@ func init() {
 	}
 	lastToolCall = &models.FuncCall{}
 	lastChat := loadOldChatOrGetNew()
-	chatBody = &models.ChatBody{
+	chatBody = models.NewSafeChatBody(&models.ChatBody{
 		Model:    "modelname",
 		Stream:   true,
 		Messages: lastChat,
-	}
+	})
 	choseChunkParser()
 	httpClient = createClient(time.Second * 90)
 	if cfg.TTS_ENABLED {
--- a/helpfuncs.go
+++ b/helpfuncs.go
@@ -43,7 +43,7 @@ func updateCachedModelColor() {
 		return
 	}
 	// Check if model is loaded
-	loaded, err := isModelLoaded(chatBody.Model)
+	loaded, err := isModelLoaded(chatBody.GetModel())
 	if err != nil {
 		// On error, assume not loaded (red)
 		cachedModelColor = "red"
@@ -103,7 +103,7 @@ func refreshChatDisplay() {
 		viewingAs = cfg.WriteNextMsgAs
 	}
 	// Filter messages for this character
-	filteredMessages := filterMessagesForCharacter(chatBody.Messages, viewingAs)
+	filteredMessages := filterMessagesForCharacter(chatBody.GetMessages(), viewingAs)
 	displayText := chatToText(filteredMessages, cfg.ShowSys)
 	textView.SetText(displayText)
 	colorText()
@@ -217,8 +217,8 @@ func startNewChat(keepSysP bool) {
 		logger.Warn("no such sys msg", "name", cfg.AssistantRole)
 	}
 	// set chat body
-	chatBody.Messages = chatBody.Messages[:2]
-	textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+	chatBody.TruncateMessages(2)
+	textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 	newChat := &models.Chat{
 		ID:        id + 1,
 		Name:      fmt.Sprintf("%d_%s", id+1, cfg.AssistantRole),
@@ -370,7 +370,7 @@ func makeStatusLine() string {
 	// Get model color based on load status for local llama.cpp models
 	modelColor := getModelColor()
 	statusLine := fmt.Sprintf(statusLineTempl, activeChatName,
-		boolColors[cfg.ToolUse], modelColor, chatBody.Model, boolColors[cfg.SkipLLMResp],
+		boolColors[cfg.ToolUse], modelColor, chatBody.GetModel(), boolColors[cfg.SkipLLMResp],
 		cfg.CurrentAPI, persona, botPersona)
 	if cfg.STT_ENABLED {
 		recordingS := fmt.Sprintf(" | [%s:-:b]voice recording[-:-:-] (ctrl+r)",
@@ -396,11 +396,11 @@ func makeStatusLine() string {
 }

 func getContextTokens() int {
-	if chatBody == nil || chatBody.Messages == nil {
+	if chatBody == nil {
 		return 0
 	}
 	total := 0
-	messages := chatBody.Messages
+	messages := chatBody.GetMessages()
 	for i := range messages {
 		msg := &messages[i]
 		if msg.Stats != nil && msg.Stats.Tokens > 0 {
@@ -415,10 +415,10 @@ func getContextTokens() int {
 const deepseekContext = 128000

 func getMaxContextTokens() int {
-	if chatBody == nil || chatBody.Model == "" {
+	if chatBody == nil || chatBody.GetModel() == "" {
 		return 0
 	}
-	modelName := chatBody.Model
+	modelName := chatBody.GetModel()
 	switch {
 	case strings.Contains(cfg.CurrentAPI, "openrouter"):
 		if orModelsData != nil {
@@ -490,7 +490,7 @@ func listChatRoles() []string {

 func deepseekModelValidator() error {
 	if cfg.CurrentAPI == cfg.DeepSeekChatAPI || cfg.CurrentAPI == cfg.DeepSeekCompletionAPI {
-		if chatBody.Model != "deepseek-chat" && chatBody.Model != "deepseek-reasoner" {
+		if chatBody.GetModel() != "deepseek-chat" && chatBody.GetModel() != "deepseek-reasoner" {
 			showToast("bad request", "wrong deepseek model name")
 			return nil
 		}
@@ -567,13 +567,13 @@ func executeCommandAndDisplay(cmdText string) {
 			outputContent := workingDir
 			// Add the command being executed to the chat
 			fmt.Fprintf(textView, "\n[-:-:b](%d) <%s>: [-:-:-]\n$ %s\n",
-				len(chatBody.Messages), cfg.ToolRole, cmdText)
+				chatBody.GetMessageCount(), cfg.ToolRole, cmdText)
 			fmt.Fprintf(textView, "%s\n", outputContent)
 			combinedMsg := models.RoleMsg{
 				Role:    cfg.ToolRole,
 				Content: "$ " + cmdText + "\n\n" + outputContent,
 			}
-			chatBody.Messages = append(chatBody.Messages, combinedMsg)
+			chatBody.AppendMessage(combinedMsg)
 			if scrollToEndEnabled {
 				textView.ScrollToEnd()
 			}
@@ -582,13 +582,13 @@ func executeCommandAndDisplay(cmdText string) {
 		} else {
 			outputContent := "cd: " + newDir + ": No such file or directory"
 			fmt.Fprintf(textView, "\n[-:-:b](%d) <%s>: [-:-:-]\n$ %s\n",
-				len(chatBody.Messages), cfg.ToolRole, cmdText)
+				chatBody.GetMessageCount(), cfg.ToolRole, cmdText)
 			fmt.Fprintf(textView, "[red]%s[-:-:-]\n", outputContent)
 			combinedMsg := models.RoleMsg{
 				Role:    cfg.ToolRole,
 				Content: "$ " + cmdText + "\n\n" + outputContent,
 			}
-			chatBody.Messages = append(chatBody.Messages, combinedMsg)
+			chatBody.AppendMessage(combinedMsg)
 			if scrollToEndEnabled {
 				textView.ScrollToEnd()
 			}
@@ -604,7 +604,7 @@ func executeCommandAndDisplay(cmdText string) {
 	output, err := cmd.CombinedOutput()
 	// Add the command being executed to the chat
 	fmt.Fprintf(textView, "\n[-:-:b](%d) <%s>: [-:-:-]\n$ %s\n",
-		len(chatBody.Messages), cfg.ToolRole, cmdText)
+		chatBody.GetMessageCount(), cfg.ToolRole, cmdText)
 	var outputContent string
 	if err != nil {
 		// Include both output and error
@@ -635,7 +635,7 @@ func executeCommandAndDisplay(cmdText string) {
 		Role:    cfg.ToolRole,
 		Content: combinedContent,
 	}
-	chatBody.Messages = append(chatBody.Messages, combinedMsg)
+	chatBody.AppendMessage(combinedMsg)
 	// Scroll to end and update colors
 	if scrollToEndEnabled {
 		textView.ScrollToEnd()
@@ -665,7 +665,7 @@ func performSearch(term string) {
 		searchResultLengths = nil
 		originalTextForSearch = ""
 		// Re-render text without highlights
-		textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+		textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 		colorText()
 		return
 	}
--- a/llm.go
+++ b/llm.go
@@ -13,8 +13,9 @@ var lastImg string             // for ctrl+j

 // containsToolSysMsg checks if the toolSysMsg already exists in the chat body
 func containsToolSysMsg() bool {
-	for i := range chatBody.Messages {
-		if chatBody.Messages[i].Role == cfg.ToolRole && chatBody.Messages[i].Content == toolSysMsg {
+	messages := chatBody.GetMessages()
+	for i := range messages {
+		if messages[i].Role == cfg.ToolRole && messages[i].Content == toolSysMsg {
 			return true
 		}
 	}
@@ -135,13 +136,13 @@ func (lcp LCPCompletion) FormMsg(msg, role string, resume bool) (io.Reader, erro
 			newMsg = models.RoleMsg{Role: role, Content: msg}
 		}
 		newMsg = *processMessageTag(&newMsg)
-		chatBody.Messages = append(chatBody.Messages, newMsg)
+		chatBody.AppendMessage(newMsg)
 	}
 	// sending description of the tools and how to use them
 	if cfg.ToolUse && !resume && role == cfg.UserRole && !containsToolSysMsg() {
-		chatBody.Messages = append(chatBody.Messages, models.RoleMsg{Role: cfg.ToolRole, Content: toolSysMsg})
+		chatBody.AppendMessage(models.RoleMsg{Role: cfg.ToolRole, Content: toolSysMsg})
 	}
-	filteredMessages, botPersona := filterMessagesForCurrentCharacter(chatBody.Messages)
+	filteredMessages, botPersona := filterMessagesForCurrentCharacter(chatBody.GetMessages())
 	// Build prompt and extract images inline as we process each message
 	messages := make([]string, len(filteredMessages))
 	for i := range filteredMessages {
@@ -183,7 +184,7 @@ func (lcp LCPCompletion) FormMsg(msg, role string, resume bool) (io.Reader, erro
 	}
 	logger.Debug("checking prompt for /completion", "tool_use", cfg.ToolUse,
 		"msg", msg, "resume", resume, "prompt", prompt, "multimodal_data_count", len(multimodalData))
-	payload := models.NewLCPReq(prompt, chatBody.Model, multimodalData,
+	payload := models.NewLCPReq(prompt, chatBody.GetModel(), multimodalData,
 		defaultLCPProps, chatBody.MakeStopSliceExcluding("", listChatRoles()))
 	data, err := json.Marshal(payload)
 	if err != nil {
@@ -289,17 +290,17 @@ func (op LCPChat) FormMsg(msg, role string, resume bool) (io.Reader, error) {
 			newMsg = models.NewRoleMsg(role, msg)
 		}
 		newMsg = *processMessageTag(&newMsg)
-		chatBody.Messages = append(chatBody.Messages, newMsg)
+		chatBody.AppendMessage(newMsg)
 		logger.Debug("LCPChat FormMsg: added message to chatBody", "role", newMsg.Role,
-			"content_len", len(newMsg.Content), "message_count_after_add", len(chatBody.Messages))
+			"content_len", len(newMsg.Content), "message_count_after_add", chatBody.GetMessageCount())
 	}
-	filteredMessages, _ := filterMessagesForCurrentCharacter(chatBody.Messages)
+	filteredMessages, _ := filterMessagesForCurrentCharacter(chatBody.GetMessages())
 	// openai /v1/chat does not support custom roles; needs to be user, assistant, system
 	// Add persona suffix to the last user message to indicate who the assistant should reply as
 	bodyCopy := &models.ChatBody{
 		Messages: make([]models.RoleMsg, len(filteredMessages)),
-		Model:    chatBody.Model,
-		Stream:   chatBody.Stream,
+		Model:    chatBody.GetModel(),
+		Stream:   chatBody.GetStream(),
 	}
 	for i := range filteredMessages {
 		strippedMsg := *stripThinkingFromMsg(&filteredMessages[i])
@@ -375,13 +376,13 @@ func (ds DeepSeekerCompletion) FormMsg(msg, role string, resume bool) (io.Reader
 	if msg != "" { // otherwise let the bot to continue
 		newMsg := models.RoleMsg{Role: role, Content: msg}
 		newMsg = *processMessageTag(&newMsg)
-		chatBody.Messages = append(chatBody.Messages, newMsg)
+		chatBody.AppendMessage(newMsg)
 	}
 	// sending description of the tools and how to use them
 	if cfg.ToolUse && !resume && role == cfg.UserRole && !containsToolSysMsg() {
-		chatBody.Messages = append(chatBody.Messages, models.RoleMsg{Role: cfg.ToolRole, Content: toolSysMsg})
+		chatBody.AppendMessage(models.RoleMsg{Role: cfg.ToolRole, Content: toolSysMsg})
 	}
-	filteredMessages, botPersona := filterMessagesForCurrentCharacter(chatBody.Messages)
+	filteredMessages, botPersona := filterMessagesForCurrentCharacter(chatBody.GetMessages())
 	messages := make([]string, len(filteredMessages))
 	for i := range filteredMessages {
 		messages[i] = stripThinkingFromMsg(&filteredMessages[i]).ToPrompt()
@@ -394,7 +395,7 @@ func (ds DeepSeekerCompletion) FormMsg(msg, role string, resume bool) (io.Reader
 	}
 	logger.Debug("checking prompt for /completion", "tool_use", cfg.ToolUse,
 		"msg", msg, "resume", resume, "prompt", prompt)
-	payload := models.NewDSCompletionReq(prompt, chatBody.Model,
+	payload := models.NewDSCompletionReq(prompt, chatBody.GetModel(),
 		defaultLCPProps["temp"],
 		chatBody.MakeStopSliceExcluding("", listChatRoles()))
 	data, err := json.Marshal(payload)
@@ -448,15 +449,15 @@ func (ds DeepSeekerChat) FormMsg(msg, role string, resume bool) (io.Reader, erro
 	if msg != "" { // otherwise let the bot continue
 		newMsg := models.RoleMsg{Role: role, Content: msg}
 		newMsg = *processMessageTag(&newMsg)
-		chatBody.Messages = append(chatBody.Messages, newMsg)
+		chatBody.AppendMessage(newMsg)
 	}
 	// Create copy of chat body with standardized user role
-	filteredMessages, _ := filterMessagesForCurrentCharacter(chatBody.Messages)
+	filteredMessages, _ := filterMessagesForCurrentCharacter(chatBody.GetMessages())
 	// Add persona suffix to the last user message to indicate who the assistant should reply as
 	bodyCopy := &models.ChatBody{
 		Messages: make([]models.RoleMsg, len(filteredMessages)),
-		Model:    chatBody.Model,
-		Stream:   chatBody.Stream,
+		Model:    chatBody.GetModel(),
+		Stream:   chatBody.GetStream(),
 	}
 	for i := range filteredMessages {
 		strippedMsg := *stripThinkingFromMsg(&filteredMessages[i])
@@ -527,13 +528,13 @@ func (or OpenRouterCompletion) FormMsg(msg, role string, resume bool) (io.Reader
 	if msg != "" { // otherwise let the bot to continue
 		newMsg := models.RoleMsg{Role: role, Content: msg}
 		newMsg = *processMessageTag(&newMsg)
-		chatBody.Messages = append(chatBody.Messages, newMsg)
+		chatBody.AppendMessage(newMsg)
 	}
 	// sending description of the tools and how to use them
 	if cfg.ToolUse && !resume && role == cfg.UserRole && !containsToolSysMsg() {
-		chatBody.Messages = append(chatBody.Messages, models.RoleMsg{Role: cfg.ToolRole, Content: toolSysMsg})
+		chatBody.AppendMessage(models.RoleMsg{Role: cfg.ToolRole, Content: toolSysMsg})
 	}
-	filteredMessages, botPersona := filterMessagesForCurrentCharacter(chatBody.Messages)
+	filteredMessages, botPersona := filterMessagesForCurrentCharacter(chatBody.GetMessages())
 	messages := make([]string, len(filteredMessages))
 	for i := range filteredMessages {
 		messages[i] = stripThinkingFromMsg(&filteredMessages[i]).ToPrompt()
@@ -547,7 +548,7 @@ func (or OpenRouterCompletion) FormMsg(msg, role string, resume bool) (io.Reader
 	stopSlice := chatBody.MakeStopSliceExcluding("", listChatRoles())
 	logger.Debug("checking prompt for /completion", "tool_use", cfg.ToolUse,
 		"msg", msg, "resume", resume, "prompt", prompt, "stop_strings", stopSlice)
-	payload := models.NewOpenRouterCompletionReq(chatBody.Model, prompt,
+	payload := models.NewOpenRouterCompletionReq(chatBody.GetModel(), prompt,
 		defaultLCPProps, stopSlice)
 	data, err := json.Marshal(payload)
 	if err != nil {
@@ -633,15 +634,15 @@ func (or OpenRouterChat) FormMsg(msg, role string, resume bool) (io.Reader, erro
 			newMsg = models.NewRoleMsg(role, msg)
 		}
 		newMsg = *processMessageTag(&newMsg)
-		chatBody.Messages = append(chatBody.Messages, newMsg)
+		chatBody.AppendMessage(newMsg)
 	}
 	// Create copy of chat body with standardized user role
-	filteredMessages, _ := filterMessagesForCurrentCharacter(chatBody.Messages)
+	filteredMessages, _ := filterMessagesForCurrentCharacter(chatBody.GetMessages())
 	// Add persona suffix to the last user message to indicate who the assistant should reply as
 	bodyCopy := &models.ChatBody{
 		Messages: make([]models.RoleMsg, len(filteredMessages)),
-		Model:    chatBody.Model,
-		Stream:   chatBody.Stream,
+		Model:    chatBody.GetModel(),
+		Stream:   chatBody.GetStream(),
 	}
 	for i := range filteredMessages {
 		strippedMsg := *stripThinkingFromMsg(&filteredMessages[i])
--- a/models/models.go
+++ b/models/models.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"os"
 	"strings"
+	"sync"
 )

 type FuncCall struct {
@@ -639,3 +640,253 @@ type MultimodalToolResp struct {
 	Type  string              `json:"type"`
 	Parts []map[string]string `json:"parts"`
 }
+
+// SafeChatBody is a thread-safe wrapper around ChatBody using RWMutex.
+// This allows safe concurrent access to chat state from multiple goroutines.
+type SafeChatBody struct {
+	mu sync.RWMutex
+	ChatBody
+}
+
+// NewSafeChatBody creates a new SafeChatBody from an existing ChatBody.
+// If cb is nil, creates an empty ChatBody.
+func NewSafeChatBody(cb *ChatBody) *SafeChatBody {
+	if cb == nil {
+		return &SafeChatBody{
+			ChatBody: ChatBody{
+				Messages: []RoleMsg{},
+			},
+		}
+	}
+	return &SafeChatBody{
+		ChatBody: *cb,
+	}
+}
+
+// GetModel returns the model name (thread-safe read).
+func (s *SafeChatBody) GetModel() string {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.Model
+}
+
+// SetModel sets the model name (thread-safe write).
+func (s *SafeChatBody) SetModel(model string) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.Model = model
+}
+
+// GetStream returns the stream flag (thread-safe read).
+func (s *SafeChatBody) GetStream() bool {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.Stream
+}
+
+// SetStream sets the stream flag (thread-safe write).
+func (s *SafeChatBody) SetStream(stream bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.Stream = stream
+}
+
+// GetMessages returns a copy of all messages (thread-safe read).
+// Returns a copy to prevent race conditions after the lock is released.
+func (s *SafeChatBody) GetMessages() []RoleMsg {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	// Return a copy to prevent external modification
+	messagesCopy := make([]RoleMsg, len(s.Messages))
+	copy(messagesCopy, s.Messages)
+	return messagesCopy
+}
+
+// SetMessages replaces all messages (thread-safe write).
+func (s *SafeChatBody) SetMessages(messages []RoleMsg) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.Messages = messages
+}
+
+// AppendMessage adds a message to the end (thread-safe write).
+func (s *SafeChatBody) AppendMessage(msg RoleMsg) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.Messages = append(s.Messages, msg)
+}
+
+// GetMessageAt returns a message at a specific index (thread-safe read).
+// Returns the message and a boolean indicating if the index was valid.
+func (s *SafeChatBody) GetMessageAt(index int) (RoleMsg, bool) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	if index < 0 || index >= len(s.Messages) {
+		return RoleMsg{}, false
+	}
+	return s.Messages[index], true
+}
+
+// SetMessageAt updates a message at a specific index (thread-safe write).
+// Returns false if index is out of bounds.
+func (s *SafeChatBody) SetMessageAt(index int, msg RoleMsg) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if index < 0 || index >= len(s.Messages) {
+		return false
+	}
+	s.Messages[index] = msg
+	return true
+}
+
+// GetLastMessage returns the last message (thread-safe read).
+// Returns the message and a boolean indicating if the chat has messages.
+func (s *SafeChatBody) GetLastMessage() (RoleMsg, bool) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	if len(s.Messages) == 0 {
+		return RoleMsg{}, false
+	}
+	return s.Messages[len(s.Messages)-1], true
+}
+
+// GetMessageCount returns the number of messages (thread-safe read).
+func (s *SafeChatBody) GetMessageCount() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.Messages)
+}
+
+// RemoveLastMessage removes the last message (thread-safe write).
+// Returns false if there are no messages.
+func (s *SafeChatBody) RemoveLastMessage() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if len(s.Messages) == 0 {
+		return false
+	}
+	s.Messages = s.Messages[:len(s.Messages)-1]
+	return true
+}
+
+// TruncateMessages keeps only the first n messages (thread-safe write).
+func (s *SafeChatBody) TruncateMessages(n int) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if n < len(s.Messages) {
+		s.Messages = s.Messages[:n]
+	}
+}
+
+// ClearMessages removes all messages (thread-safe write).
+func (s *SafeChatBody) ClearMessages() {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.Messages = []RoleMsg{}
+}
+
+// Rename renames all occurrences of oldname to newname in messages (thread-safe read-modify-write).
+func (s *SafeChatBody) Rename(oldname, newname string) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for i := range s.Messages {
+		s.Messages[i].Content = strings.ReplaceAll(s.Messages[i].Content, oldname, newname)
+		s.Messages[i].Role = strings.ReplaceAll(s.Messages[i].Role, oldname, newname)
+	}
+}
+
+// ListRoles returns all unique roles in messages (thread-safe read).
+func (s *SafeChatBody) ListRoles() []string {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	namesMap := make(map[string]struct{})
+	for i := range s.Messages {
+		namesMap[s.Messages[i].Role] = struct{}{}
+	}
+	resp := make([]string, len(namesMap))
+	i := 0
+	for k := range namesMap {
+		resp[i] = k
+		i++
+	}
+	return resp
+}
+
+// MakeStopSlice returns stop strings for all roles (thread-safe read).
+func (s *SafeChatBody) MakeStopSlice() []string {
+	return s.MakeStopSliceExcluding("", s.ListRoles())
+}
+
+// MakeStopSliceExcluding returns stop strings excluding a specific role (thread-safe read).
+func (s *SafeChatBody) MakeStopSliceExcluding(excludeRole string, roleList []string) []string {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	ss := []string{}
+	for _, role := range roleList {
+		if role == excludeRole {
+			continue
+		}
+		ss = append(ss,
+			role+":\n",
+			role+":",
+			role+": ",
+			role+":  ",
+			role+":  \n",
+			role+":   ",
+		)
+	}
+	return ss
+}
+
+// UpdateMessageFunc updates a message at index using a provided function.
+// The function receives the current message and returns the updated message.
+// This is atomic and thread-safe (read-modify-write under single lock).
+// Returns false if index is out of bounds.
+func (s *SafeChatBody) UpdateMessageFunc(index int, updater func(RoleMsg) RoleMsg) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if index < 0 || index >= len(s.Messages) {
+		return false
+	}
+	s.Messages[index] = updater(s.Messages[index])
+	return true
+}
+
+// AppendMessageFunc appends a new message created by a provided function.
+// The function receives the current message count and returns the new message.
+// This is atomic and thread-safe.
+func (s *SafeChatBody) AppendMessageFunc(creator func(count int) RoleMsg) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	msg := creator(len(s.Messages))
+	s.Messages = append(s.Messages, msg)
+}
+
+// GetMessagesForLLM returns a filtered copy of messages for sending to LLM.
+// This is thread-safe and returns a copy safe for external modification.
+func (s *SafeChatBody) GetMessagesForLLM(filterFunc func([]RoleMsg) []RoleMsg) []RoleMsg {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	if filterFunc == nil {
+		messagesCopy := make([]RoleMsg, len(s.Messages))
+		copy(messagesCopy, s.Messages)
+		return messagesCopy
+	}
+	return filterFunc(s.Messages)
+}
+
+// WithLock executes a function while holding the write lock.
+// Use this for complex operations that need to be atomic.
+func (s *SafeChatBody) WithLock(fn func(*ChatBody)) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	fn(&s.ChatBody)
+}
+
+// WithRLock executes a function while holding the read lock.
+// Use this for complex read-only operations.
+func (s *SafeChatBody) WithRLock(fn func(*ChatBody)) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	fn(&s.ChatBody)
+}
--- a/popups.go
+++ b/popups.go
@@ -50,7 +50,7 @@ func showModelSelectionPopup() {
 	// Find the current model index to set as selected
 	currentModelIndex := -1
 	for i, model := range modelList {
-		if strings.TrimPrefix(model, models.LoadedMark) == chatBody.Model {
+		if strings.TrimPrefix(model, models.LoadedMark) == chatBody.GetModel() {
 			currentModelIndex = i
 		}
 		modelListWidget.AddItem(model, "", 0, nil)
@@ -61,8 +61,8 @@ func showModelSelectionPopup() {
 	}
 	modelListWidget.SetSelectedFunc(func(index int, mainText string, secondaryText string, shortcut rune) {
 		modelName := strings.TrimPrefix(mainText, models.LoadedMark)
-		chatBody.Model = modelName
-		cfg.CurrentModel = chatBody.Model
+		chatBody.SetModel(modelName)
+		cfg.CurrentModel = chatBody.GetModel()
 		pages.RemovePage("modelSelectionPopup")
 		app.SetFocus(textArea)
 		updateCachedModelColor()
@@ -156,9 +156,9 @@ func showAPILinkSelectionPopup() {
 		}
 		newModelList := getModelListForAPI(cfg.CurrentAPI)
 		// Ensure chatBody.Model is in the new list; if not, set to first available model
-		if len(newModelList) > 0 && !slices.Contains(newModelList, chatBody.Model) {
-			chatBody.Model = strings.TrimPrefix(newModelList[0], models.LoadedMark)
-			cfg.CurrentModel = chatBody.Model
+		if len(newModelList) > 0 && !slices.Contains(newModelList, chatBody.GetModel()) {
+			chatBody.SetModel(strings.TrimPrefix(newModelList[0], models.LoadedMark))
+			cfg.CurrentModel = chatBody.GetModel()
 			updateToolCapabilities()
 		}
 		pages.RemovePage("apiLinkSelectionPopup")
@@ -229,7 +229,7 @@ func showUserRoleSelectionPopup() {
 		// Update the user role in config
 		cfg.WriteNextMsgAs = mainText
 		// role got switch, update textview with character specific context for user
-		filtered := filterMessagesForCharacter(chatBody.Messages, mainText)
+		filtered := filterMessagesForCharacter(chatBody.GetMessages(), mainText)
 		textView.SetText(chatToText(filtered, cfg.ShowSys))
 		// Remove the popup page
 		pages.RemovePage("userRoleSelectionPopup")
--- a/session.go
+++ b/session.go
@@ -29,7 +29,7 @@ func historyToSJSON(msgs []models.RoleMsg) (string, error) {
 }

 func exportChat() error {
-	data, err := json.MarshalIndent(chatBody.Messages, "", "  ")
+	data, err := json.MarshalIndent(chatBody.GetMessages(), "", "  ")
 	if err != nil {
 		return err
 	}
@@ -54,7 +54,7 @@ func importChat(filename string) error {
 	if _, ok := chatMap[activeChatName]; !ok {
 		addNewChat(activeChatName)
 	}
-	chatBody.Messages = messages
+	chatBody.SetMessages(messages)
 	cfg.AssistantRole = messages[1].Role
 	if cfg.AssistantRole == cfg.UserRole {
 		cfg.AssistantRole = messages[2].Role
--- a/tables.go
+++ b/tables.go
@@ -128,8 +128,8 @@ func makeChatTable(chatMap map[string]models.Chat) *tview.Table {
 				pages.RemovePage(historyPage)
 				return
 			}
-			chatBody.Messages = history
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			chatBody.SetMessages(history)
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			activeChatName = selectedChat
 			pages.RemovePage(historyPage)
 			return
@@ -149,8 +149,8 @@ func makeChatTable(chatMap map[string]models.Chat) *tview.Table {
 			}
 			showToast("chat deleted", selectedChat+" was deleted")
 			// load last chat
-			chatBody.Messages = loadOldChatOrGetNew()
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			chatBody.SetMessages(loadOldChatOrGetNew())
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			pages.RemovePage(historyPage)
 			return
 		case "update card":
@@ -163,16 +163,24 @@ func makeChatTable(chatMap map[string]models.Chat) *tview.Table {
 				showToast("error", "no such card: "+agentName)
 				return
 			}
-			cc.SysPrompt = chatBody.Messages[0].Content
-			cc.FirstMsg = chatBody.Messages[1].Content
+			if msg0, ok := chatBody.GetMessageAt(0); ok {
+				cc.SysPrompt = msg0.Content
+			}
+			if msg1, ok := chatBody.GetMessageAt(1); ok {
+				cc.FirstMsg = msg1.Content
+			}
 			if err := pngmeta.WriteToPng(cc.ToSpec(cfg.UserRole), cc.FilePath, cc.FilePath); err != nil {
 				logger.Error("failed to write charcard", "error", err)
 			}
 			return
 		case "move sysprompt onto 1st msg":
-			chatBody.Messages[1].Content = chatBody.Messages[0].Content + chatBody.Messages[1].Content
-			chatBody.Messages[0].Content = rpDefenitionSysMsg
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			chatBody.WithLock(func(cb *models.ChatBody) {
+				if len(cb.Messages) >= 2 {
+					cb.Messages[1].Content = cb.Messages[0].Content + cb.Messages[1].Content
+					cb.Messages[0].Content = rpDefenitionSysMsg
+				}
+			})
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			activeChatName = selectedChat
 			pages.RemovePage(historyPage)
 			return
@@ -563,7 +571,7 @@ func makeAgentTable(agentList []string) *tview.Table {
 				return
 			}
 			// replace textview
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			colorText()
 			updateStatusLine()
 			// sysModal.ClearButtons()
@@ -732,7 +740,7 @@ func makeImportChatTable(filenames []string) *tview.Table {
 			colorText()
 			updateStatusLine()
 			// redraw the text in text area
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			pages.RemovePage(historyPage)
 			app.SetFocus(textArea)
 			return
--- a/tools.go
+++ b/tools.go
@@ -1215,11 +1215,11 @@ func isCommandAllowed(command string, args ...string) bool {
 }

 func summarizeChat(args map[string]string) []byte {
-	if len(chatBody.Messages) == 0 {
+	if chatBody.GetMessageCount() == 0 {
 		return []byte("No chat history to summarize.")
 	}
 	// Format chat history for the agent
-	chatText := chatToText(chatBody.Messages, true) // include system and tool messages
+	chatText := chatToText(chatBody.GetMessages(), true) // include system and tool messages
 	return []byte(chatText)
 }

--- a/tui.go
+++ b/tui.go
@@ -355,7 +355,7 @@ func init() {
 				searchResults = nil       // Clear search results
 				searchResultLengths = nil // Clear search result lengths
 				originalTextForSearch = ""
-				textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys)) // Reset text without search regions
+				textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys)) // Reset text without search regions
 				colorText()                                                  // Apply normal chat coloring
 			} else {
 				// Original logic if no search is active
@@ -436,9 +436,11 @@ func init() {
 				pages.RemovePage(editMsgPage)
 				return nil
 			}
-			chatBody.Messages[selectedIndex].SetText(editedMsg)
+			chatBody.WithLock(func(cb *models.ChatBody) {
+				cb.Messages[selectedIndex].SetText(editedMsg)
+			})
 			// change textarea
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			pages.RemovePage(editMsgPage)
 			editMode = false
 			return nil
@@ -466,9 +468,11 @@ func init() {
 					pages.RemovePage(roleEditPage)
 					return
 				}
-				if selectedIndex >= 0 && selectedIndex < len(chatBody.Messages) {
-					chatBody.Messages[selectedIndex].Role = newRole
-					textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+				if selectedIndex >= 0 && selectedIndex < chatBody.GetMessageCount() {
+					chatBody.WithLock(func(cb *models.ChatBody) {
+						cb.Messages[selectedIndex].Role = newRole
+					})
+					textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 					colorText()
 					pages.RemovePage(roleEditPage)
 				}
@@ -497,7 +501,7 @@ func init() {
 				return nil
 			}
 			selectedIndex = siInt
-			if len(chatBody.Messages)-1 < selectedIndex || selectedIndex < 0 {
+			if chatBody.GetMessageCount()-1 < selectedIndex || selectedIndex < 0 {
 				msg := "chosen index is out of bounds, will copy user input"
 				logger.Warn(msg, "index", selectedIndex)
 				showToast("error", msg)
@@ -507,7 +511,7 @@ func init() {
 				hideIndexBar() // Hide overlay instead of removing page directly
 				return nil
 			}
-			m := chatBody.Messages[selectedIndex]
+			m := chatBody.GetMessages()[selectedIndex]
 			switch {
 			case roleEditMode:
 				hideIndexBar() // Hide overlay first
@@ -574,7 +578,7 @@ func init() {
 					searchResults = nil
 					searchResultLengths = nil
 					originalTextForSearch = ""
-					textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+					textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 					colorText()
 					return
 				} else {
@@ -632,7 +636,7 @@ func init() {
 	//
 	textArea.SetMovedFunc(updateStatusLine)
 	updateStatusLine()
-	textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+	textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 	colorText()
 	if scrollToEndEnabled {
 		textView.ScrollToEnd()
@@ -646,7 +650,7 @@ func init() {
 		if event.Key() == tcell.KeyRune && event.Rune() == '5' && event.Modifiers()&tcell.ModAlt != 0 {
 			// switch cfg.ShowSys
 			cfg.ShowSys = !cfg.ShowSys
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			colorText()
 		}
 		if event.Key() == tcell.KeyRune && event.Rune() == '3' && event.Modifiers()&tcell.ModAlt != 0 {
@@ -679,7 +683,7 @@ func init() {
 		// Handle Alt+T to toggle thinking block visibility
 		if event.Key() == tcell.KeyRune && event.Rune() == 't' && event.Modifiers()&tcell.ModAlt != 0 {
 			thinkingCollapsed = !thinkingCollapsed
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			colorText()
 			status := "expanded"
 			if thinkingCollapsed {
@@ -691,7 +695,7 @@ func init() {
 		// Handle Ctrl+T to toggle tool call/response visibility
 		if event.Key() == tcell.KeyCtrlT {
 			toolCollapsed = !toolCollapsed
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			colorText()
 			status := "expanded"
 			if toolCollapsed {
@@ -734,14 +738,14 @@ func init() {
 		}
 		if event.Key() == tcell.KeyF2 && !botRespMode {
 			// regen last msg
-			if len(chatBody.Messages) == 0 {
+			if chatBody.GetMessageCount() == 0 {
 				showToast("info", "no messages to regenerate")
 				return nil
 			}
-			chatBody.Messages = chatBody.Messages[:len(chatBody.Messages)-1]
+			chatBody.TruncateMessages(chatBody.GetMessageCount() - 1)
 			// there is no case where user msg is regenerated
-			// lastRole := chatBody.Messages[len(chatBody.Messages)-1].Role
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			// lastRole := chatBody.GetMessages()[chatBody.GetMessageCount()-1].Role
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			// go chatRound("", cfg.UserRole, textView, true, false)
 			if cfg.TTS_ENABLED {
 				TTSDoneChan <- true
@@ -760,12 +764,12 @@ func init() {
 				colorText()
 				return nil
 			}
-			if len(chatBody.Messages) == 0 {
+			if chatBody.GetMessageCount() == 0 {
 				showToast("info", "no messages to delete")
 				return nil
 			}
-			chatBody.Messages = chatBody.Messages[:len(chatBody.Messages)-1]
-			textView.SetText(chatToText(chatBody.Messages, cfg.ShowSys))
+			chatBody.TruncateMessages(chatBody.GetMessageCount() - 1)
+			textView.SetText(chatToText(chatBody.GetMessages(), cfg.ShowSys))
 			if cfg.TTS_ENABLED {
 				TTSDoneChan <- true
 			}
@@ -813,7 +817,7 @@ func init() {
 		if event.Key() == tcell.KeyF7 {
 			// copy msg to clipboard
 			editMode = false
-			m := chatBody.Messages[len(chatBody.Messages)-1]
+			m := chatBody.GetMessages()[chatBody.GetMessageCount()-1]
 			msgText := m.GetText()
 			if err := copyToClipboard(msgText); err != nil {
 				logger.Error("failed to copy to clipboard", "error", err)
@@ -997,10 +1001,10 @@ func init() {
 			TTSDoneChan <- true
 		}
 		if event.Key() == tcell.KeyRune && event.Rune() == '0' && event.Modifiers()&tcell.ModAlt != 0 && cfg.TTS_ENABLED {
-			if len(chatBody.Messages) > 0 {
+			if chatBody.GetMessageCount() > 0 {
 				// Stop any currently playing TTS first
 				TTSDoneChan <- true
-				lastMsg := chatBody.Messages[len(chatBody.Messages)-1]
+				lastMsg := chatBody.GetMessages()[chatBody.GetMessageCount()-1]
 				cleanedText := models.CleanText(lastMsg.GetText())
 				if cleanedText != "" {
 					// nolint: errcheck
@@ -1012,7 +1016,7 @@ func init() {
 		if event.Key() == tcell.KeyCtrlW {
 			// INFO: continue bot/text message
 			// without new role
-			lastRole := chatBody.Messages[len(chatBody.Messages)-1].Role
+			lastRole := chatBody.GetMessages()[chatBody.GetMessageCount()-1].Role
 			// go chatRound("", lastRole, textView, false, true)
 			chatRoundChan <- &models.ChatRoundReq{Role: lastRole, Resume: true}
 			return nil
@@ -1098,7 +1102,7 @@ func init() {
 		if event.Key() == tcell.KeyRune && event.Modifiers() == tcell.ModAlt && event.Rune() == '9' {
 			// Warm up (load) the currently selected model
 			go warmUpModel()
-			showToast("model warmup", "loading model: "+chatBody.Model)
+			showToast("model warmup", "loading model: "+chatBody.GetModel())
 			return nil
 		}
 		// cannot send msg in editMode or botRespMode
@@ -1137,7 +1141,7 @@ func init() {
 				}
 				// add user icon before user msg
 				fmt.Fprintf(textView, "%s[-:-:b](%d) <%s>: [-:-:-]\n%s\n",
-					nl, len(chatBody.Messages), persona, msgText)
+					nl, chatBody.GetMessageCount(), persona, msgText)
 				textArea.SetText("", true)
 				if scrollToEndEnabled {
 					textView.ScrollToEnd()