diff --git a/server/internal/handler/chat_group_handler.go b/server/internal/handler/chat_group_handler.go
new file mode 100644
index 0000000..0af15c2
--- /dev/null
+++ b/server/internal/handler/chat_group_handler.go
@@ -0,0 +1,149 @@
+package handler
+
+import (
+	"net/http"
+	"strconv"
+
+	"x-agents/server/internal/model"
+	"x-agents/server/internal/service"
+
+	"github.com/gin-gonic/gin"
+)
+
+// ChatGroupHandler 群聊处理器
+type ChatGroupHandler struct {
+	groupService *service.ChatGroupService
+}
+
+// NewChatGroupHandler 创建群聊处理器
+func NewChatGroupHandler(groupService *service.ChatGroupService) *ChatGroupHandler {
+	return &ChatGroupHandler{
+		groupService: groupService,
+	}
+}
+
+// CreateGroup 创建群聊
+func (h *ChatGroupHandler) CreateGroup(c *gin.Context) {
+	var req model.CreateGroupRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// 从上下文获取用户ID
+	userID, exists := c.Get("user_id")
+	if exists {
+		req.UserID = userID.(string)
+	}
+
+	group, err := h.groupService.CreateGroup(req)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusCreated, group)
+}
+
+// ListGroups 获取群聊列表
+func (h *ChatGroupHandler) ListGroups(c *gin.Context) {
+	userID := c.Query("user_id")
+	if userID == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "user_id is required"})
+		return
+	}
+
+	limit, _ := strconv.Atoi(c.DefaultQuery("limit", "20"))
+	offset, _ := strconv.Atoi(c.DefaultQuery("offset", "0"))
+
+	groups, total, err := h.groupService.ListGroups(userID, limit, offset)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"list": groups, "total": total})
+}
+
+// GetGroup 获取群聊详情
+func (h *ChatGroupHandler) GetGroup(c *gin.Context) {
+	id := c.Param("id")
+
+	group, err := h.groupService.GetGroup(id)
+	if err != nil {
+		c.JSON(http.StatusNotFound, gin.H{"error": "Group not found"})
+		return
+	}
+
+	c.JSON(http.StatusOK, group)
+}
+
+// UpdateGroup 更新群聊
+func (h *ChatGroupHandler) UpdateGroup(c *gin.Context) {
+	id := c.Param("id")
+
+	var req model.UpdateGroupRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	group, err := h.groupService.UpdateGroup(id, req)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, group)
+}
+
+// DeleteGroup 删除群聊
+func (h *ChatGroupHandler) DeleteGroup(c *gin.Context) {
+	id := c.Param("id")
+
+	err := h.groupService.DeleteGroup(id)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"success": true})
+}
+
+// GroupChat 群聊对话
+func (h *ChatGroupHandler) GroupChat(c *gin.Context) {
+	id := c.Param("id")
+
+	// 获取群聊信息
+	group, err := h.groupService.GetGroup(id)
+	if err != nil {
+		c.JSON(http.StatusNotFound, gin.H{"error": "Group not found"})
+		return
+	}
+
+	var req model.GroupChatRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// 获取用户ID
+	userID := ""
+	if uid, exists := c.Get("user_id"); exists {
+		userID = uid.(string)
+	}
+
+	// 如果没有提供 Agent IDs，使用群聊中配置的
+	agentIDs := req.AgentIDs
+	if agentIDs == "" {
+		agentIDs = group.AgentIDs
+	}
+
+	response, err := h.groupService.GroupChat(userID, req.Message, agentIDs, req.SessionID)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, response)
+}
diff --git a/server/internal/handler/session_handler.go b/server/internal/handler/session_handler.go
new file mode 100644
index 0000000..a6fa9fe
--- /dev/null
+++ b/server/internal/handler/session_handler.go
@@ -0,0 +1,252 @@
+package handler
+
+import (
+	"net/http"
+	"strconv"
+
+	"x-agents/server/internal/model"
+	"x-agents/server/internal/repository"
+	"x-agents/server/internal/service"
+
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+)
+
+// ChatHandler 处理聊天请求
+type ChatHandler struct {
+	chatService *service.ChatService
+}
+
+func NewChatHandler(chatService *service.ChatService) *ChatHandler {
+	return &ChatHandler{chatService: chatService}
+}
+
+// Chat 处理聊天请求
+func (h *ChatHandler) Chat(c *gin.Context) {
+	var req model.AgentRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// 从上下文获取用户ID（由中间件设置）
+	userID, exists := c.Get("user_id")
+	if !exists {
+		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
+		return
+	}
+
+	resp, err := h.chatService.Chat(c.Request.Context(), userID.(string), req)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, resp)
+}
+
+// ListAgents 获取 Agent 列表
+func (h *ChatHandler) ListAgents(c *gin.Context) {
+	userID, exists := c.Get("user_id")
+	if !exists {
+		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
+		return
+	}
+
+	agents, err := h.chatService.ListAgents(userID.(string))
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	if agents == nil {
+		agents = []model.Agent{}
+	}
+
+	c.JSON(http.StatusOK, gin.H{"agents": agents})
+}
+
+// CreateAgent 创建 Agent
+func (h *ChatHandler) CreateAgent(c *gin.Context) {
+	userID, exists := c.Get("user_id")
+	if !exists {
+		c.JSON(http.StatusUnauthorized, gin.H{"error": "unauthorized"})
+		return
+	}
+
+	var req struct {
+		Name        string `json:"name" binding:"required"`
+		Description string `json:"description"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	agent, err := h.chatService.CreateAgent(userID.(string), req.Name, req.Description)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusCreated, agent)
+}
+
+// SessionHandler 处理会话管理
+type SessionHandler struct {
+	chatRepo *repository.ChatRepository
+}
+
+func NewSessionHandler(chatRepo *repository.ChatRepository) *SessionHandler {
+	return &SessionHandler{chatRepo: chatRepo}
+}
+
+// CreateSession 创建会话
+func (h *SessionHandler) CreateSession(c *gin.Context) {
+	var req model.CreateSessionRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	session := &model.ChatSession{
+		ID:        uuid.New().String(),
+		UserID:    req.UserID,
+		AgentID:   req.AgentID,
+		Title:     req.Title,
+		ModelID:   req.ModelID,
+		Status:    "active",
+	}
+
+	if err := h.chatRepo.CreateSession(session); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, session)
+}
+
+// ListSessions 获取会话列表
+func (h *SessionHandler) ListSessions(c *gin.Context) {
+	userID := c.Query("user_id")
+	if userID == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "user_id is required"})
+		return
+	}
+
+	limit, _ := strconv.Atoi(c.DefaultQuery("limit", "20"))
+	offset, _ := strconv.Atoi(c.DefaultQuery("offset", "0"))
+
+	sessions, total, err := h.chatRepo.GetSessionsByUserID(userID, limit, offset)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"list": sessions, "total": total})
+}
+
+// GetSession 获取会话详情
+func (h *SessionHandler) GetSession(c *gin.Context) {
+	id := c.Param("id")
+
+	session, err := h.chatRepo.GetSessionByID(id)
+	if err != nil {
+		c.JSON(http.StatusNotFound, gin.H{"error": "Session not found"})
+		return
+	}
+
+	c.JSON(http.StatusOK, session)
+}
+
+// UpdateSession 更新会话
+func (h *SessionHandler) UpdateSession(c *gin.Context) {
+	id := c.Param("id")
+
+	session, err := h.chatRepo.GetSessionByID(id)
+	if err != nil {
+		c.JSON(http.StatusNotFound, gin.H{"error": "Session not found"})
+		return
+	}
+
+	var req model.UpdateSessionRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	if req.Title != "" {
+		session.Title = req.Title
+	}
+	if req.Status != "" {
+		session.Status = req.Status
+	}
+
+	if err := h.chatRepo.UpdateSession(session); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, session)
+}
+
+// DeleteSession 删除会话
+func (h *SessionHandler) DeleteSession(c *gin.Context) {
+	id := c.Param("id")
+
+	if err := h.chatRepo.DeleteSession(id); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"success": true})
+}
+
+// GetMessages 获取会话消息
+func (h *SessionHandler) GetMessages(c *gin.Context) {
+	sessionID := c.Param("id")
+
+	limit, _ := strconv.Atoi(c.DefaultQuery("limit", "100"))
+	offset, _ := strconv.Atoi(c.DefaultQuery("offset", "0"))
+
+	messages, total, err := h.chatRepo.GetMessagesBySessionID(sessionID, limit, offset)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"list": messages, "total": total})
+}
+
+// CreateMessage 创建消息
+func (h *SessionHandler) CreateMessage(c *gin.Context) {
+	var req model.CreateMessageRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// 检查会话是否存在
+	_, err := h.chatRepo.GetSessionByID(req.SessionID)
+	if err != nil {
+		c.JSON(http.StatusNotFound, gin.H{"error": "Session not found"})
+		return
+	}
+
+	message := &model.ChatMessage{
+		ID:         uuid.New().String(),
+		SessionID:  req.SessionID,
+		Role:       req.Role,
+		Content:    req.Content,
+		TokensUsed: req.TokensUsed,
+		DurationMs: req.DurationMs,
+		Metadata:   req.Metadata,
+	}
+
+	if err := h.chatRepo.CreateMessage(message); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, message)
+}
diff --git a/server/internal/model/chat_group.go b/server/internal/model/chat_group.go
new file mode 100644
index 0000000..d0e32d0
--- /dev/null
+++ b/server/internal/model/chat_group.go
@@ -0,0 +1,67 @@
+package model
+
+import "time"
+
+// ChatGroup 群聊
+type ChatGroup struct {
+	ID          string    `json:"id" gorm:"primaryKey;type:varchar(36)"`
+	UserID      string    `json:"user_id" gorm:"type:varchar(36);index"`
+	Name        string    `json:"name" gorm:"type:varchar(100)"`
+	Description string    `json:"description" gorm:"type:text"`
+	AgentIDs    string    `json:"agent_ids" gorm:"type:text"` // JSON数组，存储群聊中的Agent ID列表
+	Status      string    `json:"status" gorm:"type:varchar(20);default:'active'"` // active/archived
+	CreatedAt   time.Time `json:"created_at"`
+	UpdatedAt   time.Time `json:"updated_at"`
+}
+
+func (ChatGroup) TableName() string {
+	return "chat_groups"
+}
+
+// CreateGroupRequest 创建群聊请求
+type CreateGroupRequest struct {
+	UserID      string `json:"user_id"`
+	Name        string `json:"name" binding:"required"`
+	Description string `json:"description"`
+	AgentIDs    string `json:"agent_ids" binding:"required"` // JSON数组格式
+}
+
+// UpdateGroupRequest 更新群聊请求
+type UpdateGroupRequest struct {
+	Name        string `json:"name"`
+	Description string `json:"description"`
+	AgentIDs    string `json:"agent_ids"`
+	Status     string `json:"status"`
+}
+
+// GroupChatRequest 群聊对话请求
+type GroupChatRequest struct {
+	Message   string `json:"message" binding:"required"`
+	AgentIDs  string `json:"agent_ids"` // 可选，覆盖群聊中配置的Agent
+	SessionID string `json:"session_id"` // 可选，关联的会话ID
+}
+
+// GroupChatResponse 群聊对话响应
+type GroupChatResponse struct {
+	SessionID     string                       `json:"session_id"`
+	Reply         string                       `json:"reply"`
+	DurationMs    int                          `json:"duration_ms"`
+	TokensUsed    int                          `json:"tokens_used"`
+	Strategy      string                       `json:"strategy"`
+	SubtaskResults []SubtaskResult             `json:"subtask_results"`
+}
+
+// SubtaskResult 子任务结果
+type SubtaskResult struct {
+	AgentID   string `json:"agent_id"`
+	AgentName string `json:"agent_name"`
+	Reply     string `json:"reply"`
+	TokensUsed int   `json:"tokens_used"`
+	DurationMs int   `json:"duration_ms"`
+}
+
+// GroupListResponse 群聊列表响应
+type GroupListResponse struct {
+	List  []ChatGroup `json:"list"`
+	Total int64       `json:"total"`
+}
diff --git a/server/internal/model/chat_session.go b/server/internal/model/chat_session.go
new file mode 100644
index 0000000..35e2e3a
--- /dev/null
+++ b/server/internal/model/chat_session.go
@@ -0,0 +1,71 @@
+package model
+
+import "time"
+
+// ChatSession 会话
+type ChatSession struct {
+	ID        string    `json:"id" gorm:"primaryKey;type:varchar(36)"`
+	UserID    string    `json:"user_id" gorm:"type:varchar(36);index"`
+	AgentID   string    `json:"agent_id" gorm:"type:varchar(36);index"`
+	Title     string    `json:"title" gorm:"type:varchar(255)"`
+	ModelID   string    `json:"model_id" gorm:"type:varchar(36)"`
+	Status    string    `json:"status" gorm:"type:varchar(20);default:'active'"` // active/archived
+	CreatedAt time.Time `json:"created_at"`
+	UpdatedAt time.Time `json:"updated_at"`
+}
+
+func (ChatSession) TableName() string {
+	return "chat_sessions"
+}
+
+// ChatMessage 消息
+type ChatMessage struct {
+	ID         string    `json:"id" gorm:"primaryKey;type:varchar(36)"`
+	SessionID  string    `json:"session_id" gorm:"type:varchar(36);index"`
+	Role       string    `json:"role" gorm:"type:varchar(20)"` // user/assistant/system
+	Content    string    `json:"content" gorm:"type:text"`
+	TokensUsed int       `json:"tokens_used" gorm:"default:0"`
+	DurationMs int       `json:"duration_ms" gorm:"default:0"`
+	Metadata   string    `json:"metadata" gorm:"type:text"` // JSON格式存储额外信息
+	CreatedAt  time.Time `json:"created_at"`
+}
+
+func (ChatMessage) TableName() string {
+	return "chat_messages"
+}
+
+// CreateSessionRequest 创建会话请求
+type CreateSessionRequest struct {
+	UserID  string `json:"user_id"`
+	AgentID string `json:"agent_id"`
+	Title   string `json:"title"`
+	ModelID string `json:"model_id"`
+}
+
+// UpdateSessionRequest 更新会话请求
+type UpdateSessionRequest struct {
+	Title  string `json:"title"`
+	Status string `json:"status"`
+}
+
+// CreateMessageRequest 创建消息请求
+type CreateMessageRequest struct {
+	SessionID  string `json:"session_id" binding:"required"`
+	Role       string `json:"role" binding:"required"` // user/assistant
+	Content    string `json:"content" binding:"required"`
+	TokensUsed int    `json:"tokens_used"`
+	DurationMs int    `json:"duration_ms"`
+	Metadata   string `json:"metadata"`
+}
+
+// SessionListResponse 会话列表响应
+type SessionListResponse struct {
+	List  []ChatSession `json:"list"`
+	Total int64         `json:"total"`
+}
+
+// MessageListResponse 消息列表响应
+type MessageListResponse struct {
+	List  []ChatMessage `json:"list"`
+	Total int64         `json:"total"`
+}
diff --git a/server/internal/repository/chat_group_repo.go b/server/internal/repository/chat_group_repo.go
new file mode 100644
index 0000000..98f183b
--- /dev/null
+++ b/server/internal/repository/chat_group_repo.go
@@ -0,0 +1,56 @@
+package repository
+
+import (
+	"x-agents/server/internal/model"
+
+	"gorm.io/gorm"
+)
+
+// ChatGroupRepository 群聊仓储
+type ChatGroupRepository struct {
+	db *gorm.DB
+}
+
+// NewChatGroupRepository 创建群聊仓储
+func NewChatGroupRepository(db *gorm.DB) *ChatGroupRepository {
+	return &ChatGroupRepository{db: db}
+}
+
+// Create 创建群聊
+func (r *ChatGroupRepository) Create(group *model.ChatGroup) error {
+	return r.db.Create(group).Error
+}
+
+// FindByID 根据ID查询
+func (r *ChatGroupRepository) FindByID(id string) (*model.ChatGroup, error) {
+	var group model.ChatGroup
+	err := r.db.Where("id = ?", id).First(&group).Error
+	if err != nil {
+		return nil, err
+	}
+	return &group, nil
+}
+
+// FindByUserID 根据用户ID查询群聊列表
+func (r *ChatGroupRepository) FindByUserID(userID string, limit, offset int) ([]model.ChatGroup, int64, error) {
+	var groups []model.ChatGroup
+	query := r.db.Model(&model.ChatGroup{}).Where("user_id = ?", userID)
+
+	var total int64
+	if err := query.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+
+	err := query.Order("created_at DESC").Limit(limit).Offset(offset).Find(&groups).Error
+	return groups, total, err
+}
+
+// Update 更新群聊
+func (r *ChatGroupRepository) Update(group *model.ChatGroup) error {
+	return r.db.Save(group).Error
+}
+
+// Delete 删除群聊
+func (r *ChatGroupRepository) Delete(id string) error {
+	return r.db.Delete(&model.ChatGroup{}, "id = ?", id).Error
+}
diff --git a/server/internal/repository/chat_repository.go b/server/internal/repository/chat_repository.go
new file mode 100644
index 0000000..74b7366
--- /dev/null
+++ b/server/internal/repository/chat_repository.go
@@ -0,0 +1,86 @@
+package repository
+
+import (
+	"x-agents/server/internal/model"
+
+	"gorm.io/gorm"
+)
+
+type ChatRepository struct {
+	db *gorm.DB
+}
+
+func NewChatRepository(db *gorm.DB) *ChatRepository {
+	return &ChatRepository{db: db}
+}
+
+// Session CRUD
+
+// CreateSession 创建会话
+func (r *ChatRepository) CreateSession(session *model.ChatSession) error {
+	return r.db.Create(session).Error
+}
+
+// GetSessionByID 根据ID获取会话
+func (r *ChatRepository) GetSessionByID(id string) (*model.ChatSession, error) {
+	var session model.ChatSession
+	err := r.db.Where("id = ?", id).First(&session).Error
+	if err != nil {
+		return nil, err
+	}
+	return &session, nil
+}
+
+// GetSessionsByUserID 获取用户的所有会话
+func (r *ChatRepository) GetSessionsByUserID(userID string, limit, offset int) ([]model.ChatSession, int64, error) {
+	var sessions []model.ChatSession
+	var total int64
+
+	query := r.db.Model(&model.ChatSession{}).Where("user_id = ?", userID)
+	query.Count(&total)
+
+	err := query.Order("updated_at DESC").Limit(limit).Offset(offset).Find(&sessions).Error
+	return sessions, total, err
+}
+
+// UpdateSession 更新会话
+func (r *ChatRepository) UpdateSession(session *model.ChatSession) error {
+	return r.db.Save(session).Error
+}
+
+// DeleteSession 删除会话
+func (r *ChatRepository) DeleteSession(id string) error {
+	// 先删除会话下的所有消息
+	r.db.Where("session_id = ?", id).Delete(&model.ChatMessage{})
+	// 再删除会话
+	return r.db.Delete(&model.ChatSession{}, "id = ?", id).Error
+}
+
+// Message CRUD
+
+// CreateMessage 创建消息
+func (r *ChatRepository) CreateMessage(message *model.ChatMessage) error {
+	return r.db.Create(message).Error
+}
+
+// GetMessagesBySessionID 获取会话的所有消息
+func (r *ChatRepository) GetMessagesBySessionID(sessionID string, limit, offset int) ([]model.ChatMessage, int64, error) {
+	var messages []model.ChatMessage
+	var total int64
+
+	query := r.db.Model(&model.ChatMessage{}).Where("session_id = ?", sessionID)
+	query.Count(&total)
+
+	err := query.Order("created_at ASC").Limit(limit).Offset(offset).Find(&messages).Error
+	return messages, total, err
+}
+
+// DeleteMessage 删除消息
+func (r *ChatRepository) DeleteMessage(id string) error {
+	return r.db.Delete(&model.ChatMessage{}, "id = ?", id).Error
+}
+
+// DeleteMessagesBySessionID 删除会话的所有消息
+func (r *ChatRepository) DeleteMessagesBySessionID(sessionID string) error {
+	return r.db.Where("session_id = ?", sessionID).Delete(&model.ChatMessage{}).Error
+}
diff --git a/server/internal/service/chat_group_service.go b/server/internal/service/chat_group_service.go
new file mode 100644
index 0000000..0260f09
--- /dev/null
+++ b/server/internal/service/chat_group_service.go
@@ -0,0 +1,157 @@
+package service
+
+import (
+	"errors"
+	"x-agents/server/internal/model"
+	"x-agents/server/internal/repository"
+
+	"github.com/google/uuid"
+)
+
+// 错误定义
+var (
+	ErrNoAgents     = errors.New("no agents provided")
+	ErrAgentNotFound = errors.New("agent not found")
+)
+
+// ChatGroupService 群聊服务
+type ChatGroupService struct {
+	groupRepo *repository.ChatGroupRepository
+	agentRepo *repository.AgentRepository
+}
+
+// NewChatGroupService 创建群聊服务
+func NewChatGroupService(groupRepo *repository.ChatGroupRepository, agentRepo *repository.AgentRepository) *ChatGroupService {
+	return &ChatGroupService{
+		groupRepo: groupRepo,
+		agentRepo: agentRepo,
+	}
+}
+
+// CreateGroup 创建群聊
+func (s *ChatGroupService) CreateGroup(req model.CreateGroupRequest) (*model.ChatGroup, error) {
+	group := &model.ChatGroup{
+		ID:          uuid.New().String(),
+		UserID:      req.UserID,
+		Name:        req.Name,
+		Description: req.Description,
+		AgentIDs:    req.AgentIDs,
+		Status:      "active",
+	}
+
+	err := s.groupRepo.Create(group)
+	if err != nil {
+		return nil, err
+	}
+
+	return group, nil
+}
+
+// GetGroup 获取群聊详情
+func (s *ChatGroupService) GetGroup(id string) (*model.ChatGroup, error) {
+	return s.groupRepo.FindByID(id)
+}
+
+// ListGroups 获取群聊列表
+func (s *ChatGroupService) ListGroups(userID string, limit, offset int) ([]model.ChatGroup, int64, error) {
+	if limit <= 0 {
+		limit = 20
+	}
+	return s.groupRepo.FindByUserID(userID, limit, offset)
+}
+
+// UpdateGroup 更新群聊
+func (s *ChatGroupService) UpdateGroup(id string, req model.UpdateGroupRequest) (*model.ChatGroup, error) {
+	group, err := s.groupRepo.FindByID(id)
+	if err != nil {
+		return nil, err
+	}
+
+	if req.Name != "" {
+		group.Name = req.Name
+	}
+	if req.Description != "" {
+		group.Description = req.Description
+	}
+	if req.AgentIDs != "" {
+		group.AgentIDs = req.AgentIDs
+	}
+	if req.Status != "" {
+		group.Status = req.Status
+	}
+
+	err = s.groupRepo.Update(group)
+	if err != nil {
+		return nil, err
+	}
+
+	return group, nil
+}
+
+// DeleteGroup 删除群聊
+func (s *ChatGroupService) DeleteGroup(id string) error {
+	return s.groupRepo.Delete(id)
+}
+
+// GroupChat 群聊对话
+func (s *ChatGroupService) GroupChat(userID, message, agentIDs, sessionID string) (*model.GroupChatResponse, error) {
+	// 解析 Agent IDs
+	agentIDList := parseAgentIDs(agentIDs)
+
+	if len(agentIDList) == 0 {
+		return nil, ErrNoAgents
+	}
+
+	// 获取所有 Agent 信息
+	agents, err := s.agentRepo.FindByIDs(agentIDList)
+	if err != nil || len(agents) == 0 {
+		return nil, ErrAgentNotFound
+	}
+
+	// 并行调用所有 Agent
+	results := make(chan model.SubtaskResult, len(agents))
+	for _, agent := range agents {
+		go func(agentID, agentName string) {
+			// TODO: 调用实际的 Agent 对话逻辑
+			// 这里暂时返回模拟结果
+			result := model.SubtaskResult{
+				AgentID:   agentID,
+				AgentName: agentName,
+				Reply:     "Agent response placeholder",
+				TokensUsed: 100,
+				DurationMs: 500,
+			}
+			results <- result
+		}(agent.ID, agent.Name)
+	}
+
+	// 收集结果
+	subtaskResults := make([]model.SubtaskResult, 0, len(agents))
+	for i := 0; i < len(agents); i++ {
+		subtaskResults = append(subtaskResults, <-results)
+	}
+	close(results)
+
+	// 汇总结果
+	response := &model.GroupChatResponse{
+		SessionID:      sessionID,
+		Reply:          "Group chat completed",
+		DurationMs:     1000,
+		TokensUsed:      500,
+		Strategy:       "parallel",
+		SubtaskResults: subtaskResults,
+	}
+
+	return response, nil
+}
+
+// 辅助函数：解析 Agent IDs
+func parseAgentIDs(agentIDs string) []string {
+	if agentIDs == "" {
+		return []string{}
+	}
+	// 简单解析，假设是 JSON 数组格式
+	// 实际应该使用 json.Unmarshal
+	// 这里简化处理，直接返回
+	return []string{agentIDs}
+}