diff --git a/pkg/agent/loop.go b/pkg/agent/loop.go
index e16a691..3625858 100644
--- a/pkg/agent/loop.go
+++ b/pkg/agent/loop.go
@@ -137,6 +137,14 @@ type StartupSelfCheckReport struct {
 	CompactedSessions int
 }
 
+type tokenUsageTotals struct {
+	input  int
+	output int
+	total  int
+}
+
+type tokenUsageTotalsKey struct{}
+
 func (sr *stageReporter) Publish(stage int, total int, status string, detail string) {
 	if sr == nil || sr.onUpdate == nil {
 		return
@@ -405,6 +413,7 @@ func (al *AgentLoop) runSessionWorker(ctx context.Context, sessionKey string, wo
 		case msg := <-worker.queue:
 			func() {
 				taskCtx, cancel := context.WithCancel(ctx)
+				taskCtx, tokenTotals := withTokenUsageTotals(taskCtx)
 				worker.cancelMu.Lock()
 				worker.cancel = cancel
 				worker.cancelMu.Unlock()
@@ -429,6 +438,17 @@ func (al *AgentLoop) runSessionWorker(ctx context.Context, sessionKey string, wo
 				}
 
 				if response != "" && shouldPublishSyntheticResponse(msg) {
+					if al != nil && al.sessions != nil && tokenTotals != nil {
+						al.sessions.AddTokenUsage(
+							msg.SessionKey,
+							tokenTotals.input,
+							tokenTotals.output,
+							tokenTotals.total,
+						)
+					}
+					response += formatTokenUsageSuffix(
+						tokenTotals,
+					)
 					al.bus.PublishOutbound(bus.OutboundMessage{
 						Buttons: nil,
 						Channel: msg.Channel,
@@ -919,6 +939,49 @@ func shouldHandleControlIntents(msg bus.InboundMessage) bool {
 	return !isSyntheticMessage(msg)
 }
 
+func withTokenUsageTotals(ctx context.Context) (context.Context, *tokenUsageTotals) {
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	totals := &tokenUsageTotals{}
+	return context.WithValue(ctx, tokenUsageTotalsKey{}, totals), totals
+}
+
+func tokenUsageTotalsFromContext(ctx context.Context) *tokenUsageTotals {
+	if ctx == nil {
+		return nil
+	}
+	totals, _ := ctx.Value(tokenUsageTotalsKey{}).(*tokenUsageTotals)
+	return totals
+}
+
+func addTokenUsageToContext(ctx context.Context, usage *providers.UsageInfo) {
+	totals := tokenUsageTotalsFromContext(ctx)
+	if totals == nil || usage == nil {
+		return
+	}
+	totals.input += usage.PromptTokens
+	totals.output += usage.CompletionTokens
+	if usage.TotalTokens > 0 {
+		totals.total += usage.TotalTokens
+	} else {
+		totals.total += usage.PromptTokens + usage.CompletionTokens
+	}
+}
+
+func formatTokenUsageSuffix(totals *tokenUsageTotals) string {
+	input := 0
+	output := 0
+	total := 0
+	if totals != nil {
+		input = totals.input
+		output = totals.output
+		total = totals.total
+	}
+	return fmt.Sprintf("\n\nUsage: in %d, out %d, total %d",
+		input, output, total)
+}
+
 func withUserLanguageHint(ctx context.Context, sessionKey, content string) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
@@ -943,14 +1006,11 @@ func (al *AgentLoop) naturalizeUserFacingText(ctx context.Context, fallback stri
 	}
 
 	targetLanguage := "English"
-	if al != nil {
-		if hint, ok := ctx.Value(userLanguageHintKey{}).(userLanguageHint); ok {
-			if al.preferChineseUserFacingText(hint.sessionKey, hint.content) {
-				targetLanguage = "Simplified Chinese"
-			}
+	if hint, ok := ctx.Value(userLanguageHintKey{}).(userLanguageHint); ok {
+		if al.preferChineseUserFacingText(hint.sessionKey, hint.content) {
+			targetLanguage = "Simplified Chinese"
 		}
 	}
-
 	llmCtx, cancel := context.WithTimeout(ctx, 4*time.Second)
 	defer cancel()
 
@@ -1717,6 +1777,7 @@ func (al *AgentLoop) callLLMWithModelFallback(
 		for idx, model := range candidates {
 			response, err := al.provider.Chat(ctx, messages, tools, model, options)
 			if err == nil {
+				addTokenUsageToContext(ctx, response.Usage)
 				if al.model != model {
 					logger.WarnCF("agent", "Model switched after quota/rate-limit error", map[string]interface{}{
 						"from_model": al.model,
@@ -1761,6 +1822,7 @@ func (al *AgentLoop) callLLMWithModelFallback(
 		for midx, model := range modelCandidates {
 			response, err := proxyProvider.Chat(ctx, messages, tools, model, options)
 			if err == nil {
+				addTokenUsageToContext(ctx, response.Usage)
 				if al.proxy != proxyName {
 					logger.WarnCF("agent", "Proxy switched after model unavailability", map[string]interface{}{
 						"from_proxy": al.proxy,
diff --git a/pkg/session/manager.go b/pkg/session/manager.go
index c2ddf2e..68af46c 100644
--- a/pkg/session/manager.go
+++ b/pkg/session/manager.go
@@ -19,6 +19,9 @@ type Session struct {
 	Key      string              `json:"key"`
 	Messages []providers.Message `json:"messages"`
 	Summary  string              `json:"summary,omitempty"`
+	TokenIn  int                 `json:"token_in,omitempty"`
+	TokenOut int                 `json:"token_out,omitempty"`
+	TokenSum int                 `json:"token_sum,omitempty"`
 	Created  time.Time           `json:"created"`
 	Updated  time.Time           `json:"updated"`
 	mu       sync.RWMutex
@@ -283,11 +286,23 @@ func (sm *SessionManager) Save(session *Session) error {
 		return nil
 	}
 
+	session.mu.RLock()
+	summary := session.Summary
+	updated := session.Updated
+	created := session.Created
+	tokenIn := session.TokenIn
+	tokenOut := session.TokenOut
+	tokenSum := session.TokenSum
+	session.mu.RUnlock()
+
 	metaPath := filepath.Join(sm.storage, session.Key+".meta")
 	meta := map[string]interface{}{
-		"summary": session.Summary,
-		"updated": session.Updated,
-		"created": session.Created,
+		"summary":   summary,
+		"updated":   updated,
+		"created":   created,
+		"token_in":  tokenIn,
+		"token_out": tokenOut,
+		"token_sum": tokenSum,
 	}
 	data, err := json.MarshalIndent(meta, "", "  ")
 	if err != nil {
@@ -296,6 +311,29 @@ func (sm *SessionManager) Save(session *Session) error {
 	return os.WriteFile(metaPath, data, 0644)
 }
 
+func (sm *SessionManager) AddTokenUsage(sessionKey string, in, out, sum int) {
+	session := sm.GetOrCreate(sessionKey)
+	if sum <= 0 {
+		sum = in + out
+	}
+
+	session.mu.Lock()
+	session.TokenIn += in
+	session.TokenOut += out
+	session.TokenSum += sum
+	session.Updated = time.Now()
+	session.mu.Unlock()
+
+	if sm.storage != "" {
+		if err := sm.Save(session); err != nil {
+			logger.WarnCF("session", "Failed to persist token usage", map[string]interface{}{
+				"session_key":     sessionKey,
+				logger.FieldError: err.Error(),
+			})
+		}
+	}
+}
+
 func (sm *SessionManager) loadSessions() error {
 	files, err := os.ReadDir(sm.storage)
 	if err != nil {
@@ -342,14 +380,20 @@ func (sm *SessionManager) loadSessions() error {
 			data, err := os.ReadFile(filepath.Join(sm.storage, file.Name()))
 			if err == nil {
 				var meta struct {
-					Summary string    `json:"summary"`
-					Updated time.Time `json:"updated"`
-					Created time.Time `json:"created"`
+					Summary  string    `json:"summary"`
+					Updated  time.Time `json:"updated"`
+					Created  time.Time `json:"created"`
+					TokenIn  int       `json:"token_in"`
+					TokenOut int       `json:"token_out"`
+					TokenSum int       `json:"token_sum"`
 				}
 				if err := json.Unmarshal(data, &meta); err == nil {
 					session.Summary = meta.Summary
 					session.Updated = meta.Updated
 					session.Created = meta.Created
+					session.TokenIn = meta.TokenIn
+					session.TokenOut = meta.TokenOut
+					session.TokenSum = meta.TokenSum
 				}
 			}
 		}