diff --git a/config/config.example.json b/config/config.example.json
index 77a8c0683..b3a26f811 100644
--- a/config/config.example.json
+++ b/config/config.example.json
@@ -9,6 +9,11 @@
       "max_tool_iterations": 20
     }
   },
+  "session": {
+    "memory_message_limit": 20,
+    "memory_token_percent": 75,
+    "memory_notify_user": false
+  },
   "model_list": [
     {
       "model_name": "gpt4",
diff --git a/pkg/agent/loop.go b/pkg/agent/loop.go
index b36f4a0c4..3d9da2946 100644
--- a/pkg/agent/loop.go
+++ b/pkg/agent/loop.go
@@ -29,6 +29,11 @@ import (
 	"github.com/sipeed/picoclaw/pkg/utils"
 )
 
+const (
+	defaultMemoryMessageLimit = 20
+	defaultMemoryTokenPercent = 75
+)
+
 type AgentLoop struct {
 	bus            *bus.MessageBus
 	cfg            *config.Config
@@ -747,19 +752,35 @@ func (al *AgentLoop) updateToolContexts(agent *AgentInstance, channel, chatID st
 func (al *AgentLoop) maybeSummarize(agent *AgentInstance, sessionKey, channel, chatID string) {
 	newHistory := agent.Sessions.GetHistory(sessionKey)
 	tokenEstimate := al.estimateTokens(newHistory)
-	threshold := agent.ContextWindow * 75 / 100
 
-	if len(newHistory) > 20 || tokenEstimate > threshold {
+	msgLimit := defaultMemoryMessageLimit
+	tokenPercent := defaultMemoryTokenPercent
+	notifyUser := false
+	if al.cfg != nil {
+		if al.cfg.Session.MemoryMessageLimit > 0 {
+			msgLimit = al.cfg.Session.MemoryMessageLimit
+		}
+		if al.cfg.Session.MemoryTokenPercent > 0 {
+			tokenPercent = al.cfg.Session.MemoryTokenPercent
+		}
+		notifyUser = al.cfg.Session.MemoryNotifyUser
+	}
+	threshold := agent.ContextWindow * tokenPercent / 100
+
+	if len(newHistory) > msgLimit || tokenEstimate > threshold {
 		summarizeKey := agent.ID + ":" + sessionKey
 		if _, loading := al.summarizing.LoadOrStore(summarizeKey, true); !loading {
 			go func() {
 				defer al.summarizing.Delete(summarizeKey)
-				if !constants.IsInternalChannel(channel) {
+				if notifyUser && !constants.IsInternalChannel(channel) {
 					al.bus.PublishOutbound(bus.OutboundMessage{
 						Channel: channel,
 						ChatID:  chatID,
 						Content: "Memory threshold reached. Optimizing conversation history...",
 					})
+				} else if !constants.IsInternalChannel(channel) {
+					logger.InfoCF("agent", "Memory threshold reached, optimizing conversation history",
+						map[string]interface{}{"session_key": sessionKey})
 				}
 				al.summarizeSession(agent, sessionKey)
 			}()
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 20556011a..b0684bb8d 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -164,6 +164,10 @@ type AgentBinding struct {
 type SessionConfig struct {
 	DMScope       string              `json:"dm_scope,omitempty"`
 	IdentityLinks map[string][]string `json:"identity_links,omitempty"`
+	// Memory summarization: trigger when history exceeds message count or token percent of context window
+	MemoryMessageLimit int  `json:"memory_message_limit,omitempty"` // default 20
+	MemoryTokenPercent int  `json:"memory_token_percent,omitempty"` // default 75
+	MemoryNotifyUser   bool `json:"memory_notify_user,omitempty"`   // if true, send "Memory threshold reached..." to user; default false
 }
 
 type AgentDefaults struct {