feat: add /stats command for session statistics

- Add /stats command to display session metrics (messages, tokens, cost)
- Refactor stats calculation into separate module
- Update logging provider to track token usage
- Add stats display on session end

cmd/picoclaw/internal/stats/command.go

@@ -0,0 +1,118 @@
+package stats
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+
+	"github.com/sipeed/picoclaw/cmd/picoclaw/internal"
+	"github.com/sipeed/picoclaw/pkg/llmlog"
+)
+
+func NewStatsCommand() *cobra.Command {
+	var days int
+	var model string
+	var logDir string
+
+	cmd := &cobra.Command{
+		Use:     "stats",
+		Aliases: []string{"stat"},
+		Short:   "Show token usage statistics",
+		Long:    "Display token usage statistics from LLM call logs",
+		Example: `  picoclaw stats                  # Show all time statistics
+  picoclaw stats --days 7         # Show last 7 days statistics
+  picoclaw stats --days 30        # Show last 30 days statistics
+  picoclaw stats --model gpt-4o   # Filter by model
+  picoclaw stats --log-dir /path/to/logs  # Specify log directory`,
+		Run: func(cmd *cobra.Command, args []string) {
+			// Find log directory
+			resolvedLogDir := findLogDir(logDir)
+			if resolvedLogDir == "" {
+				fmt.Println("❌ 无法找到日志目录")
+				fmt.Println("提示: 使用 --log-dir 指定日志目录，或在配置文件中设置 tools.llm_call_log.log_dir")
+				os.Exit(1)
+			}
+
+			// Calculate statistics
+			result, err := llmlog.CalculateStats(resolvedLogDir, days, model)
+			if err != nil {
+				fmt.Printf("❌ Stats calculation failed: %v\n", err)
+				os.Exit(1)
+			}
+
+			// Print result
+			fmt.Println(llmlog.FormatStatsTable(result))
+		},
+	}
+
+	cmd.Flags().IntVarP(&days, "days", "d", 0, "Number of days to include (0 means all time)")
+	cmd.Flags().StringVarP(&model, "model", "m", "", "Filter by specific model")
+	cmd.Flags().StringVarP(&logDir, "log-dir", "l", "", "Log directory path (overrides config)")
+
+	return cmd
+}
+
+// findLogDir finds the LLM log directory with the following priority:
+// 1. Explicitly provided logDir parameter
+// 2. Config file: tools.llm_call_log.log_dir
+// 3. Environment variable: PICOCLAW_TOOLS_LLM_CALL_LOG_DIR
+// 4. Default locations: ~/.picoclaw/logs/llmcall, ~/picoclaw/workspace/logs/llmcall
+func findLogDir(logDir string) string {
+	// 1. Check explicit parameter
+	if logDir != "" {
+		if _, err := os.Stat(logDir); err == nil {
+			return logDir
+		}
+		// If explicitly provided but doesn't exist, still return it
+		// (error will be reported later)
+		return logDir
+	}
+
+	// 2. Check config file and environment variable
+	cfg, err := internal.LoadConfig()
+	if err == nil && cfg.Tools.LLMCallLog.LogDir != "" {
+		if _, err := os.Stat(cfg.Tools.LLMCallLog.LogDir); err == nil {
+			return cfg.Tools.LLMCallLog.LogDir
+		}
+	}
+
+	// 3. Check environment variable directly (in case config loading failed)
+	if envDir := os.Getenv("PICOCLAW_TOOLS_LLM_CALL_LOG_DIR"); envDir != "" {
+		if _, err := os.Stat(envDir); err == nil {
+			return envDir
+		}
+	}
+
+	// 4. Check default locations
+	homeDir, err := os.UserHomeDir()
+	if err != nil {
+		return ""
+	}
+
+	// Default: ~/.picoclaw/logs/llmcall
+	defaultDir := filepath.Join(homeDir, ".picoclaw", "logs", "llmcall")
+	if _, err := os.Stat(defaultDir); err == nil {
+		return defaultDir
+	}
+
+	// Alternative: workspace logs
+	workspaceLogDir := filepath.Join(homeDir, "picoclaw", "workspace", "logs", "llmcall")
+	if _, err := os.Stat(workspaceLogDir); err == nil {
+		return workspaceLogDir
+	}
+
+	// Legacy: check old directory names for backward compatibility
+	legacyDir := filepath.Join(homeDir, ".picoclaw", "logs", "llm")
+	if _, err := os.Stat(legacyDir); err == nil {
+		return legacyDir
+	}
+
+	legacyWorkspaceDir := filepath.Join(homeDir, "picoclaw", "workspace", "logs", "llm")
+	if _, err := os.Stat(legacyWorkspaceDir); err == nil {
+		return legacyWorkspaceDir
+	}
+
+	return ""
+}

cmd/picoclaw/main.go

@@ -20,6 +20,7 @@ import (
 	"github.com/sipeed/picoclaw/cmd/picoclaw/internal/migrate"
 	"github.com/sipeed/picoclaw/cmd/picoclaw/internal/onboard"
 	"github.com/sipeed/picoclaw/cmd/picoclaw/internal/skills"
+	"github.com/sipeed/picoclaw/cmd/picoclaw/internal/stats"
 	"github.com/sipeed/picoclaw/cmd/picoclaw/internal/status"
 	"github.com/sipeed/picoclaw/cmd/picoclaw/internal/version"
 )
@@ -42,6 +43,7 @@ func NewPicoclawCommand() *cobra.Command {
 		cron.NewCronCommand(),
 		migrate.NewMigrateCommand(),
 		skills.NewSkillsCommand(),
+		stats.NewStatsCommand(),
 		version.NewVersionCommand(),
 	)
 

cmd/picoclaw/main_test.go

@@ -40,6 +40,7 @@ func TestNewPicoclawCommand(t *testing.T) {
 		"migrate",
 		"onboard",
 		"skills",
+		"stats",
 		"status",
 		"version",
 	}

pkg/agent/loop.go

@@ -52,6 +52,10 @@ type AgentLoop struct {
 	// Task cancellation support
 	currentCancel   context.CancelFunc
 	currentCancelMu sync.Mutex
+
+	// Token statistics for current session
+	tokenStats   *commands.TokenStats
+	tokenStatsMu sync.RWMutex
 }
 
 // processOptions configures how a message is processed
@@ -432,6 +436,34 @@ func (al *AgentLoop) CancelCurrentTask() bool {
 	return true
 }
 
+// updateTokenStats updates the token statistics for the current session.
+func (al *AgentLoop) updateTokenStats(model string, promptTokens, completionTokens int) {
+	al.tokenStatsMu.Lock()
+	defer al.tokenStatsMu.Unlock()
+
+	if al.tokenStats == nil {
+		al.tokenStats = &commands.TokenStats{Model: model}
+	}
+	al.tokenStats.PromptTokens += promptTokens
+	al.tokenStats.CompletionTokens += completionTokens
+	al.tokenStats.TotalTokens += promptTokens + completionTokens
+	al.tokenStats.CallCount++
+}
+
+// getTokenStats returns the current session's token statistics.
+func (al *AgentLoop) getTokenStats() *commands.TokenStats {
+	al.tokenStatsMu.RLock()
+	defer al.tokenStatsMu.RUnlock()
+	return al.tokenStats
+}
+
+// resetTokenStats resets the token statistics for a new session.
+func (al *AgentLoop) resetTokenStats() {
+	al.tokenStatsMu.Lock()
+	defer al.tokenStatsMu.Unlock()
+	al.tokenStats = nil
+}
+
 func (al *AgentLoop) RegisterTool(tool tools.Tool) {
 	for _, agentID := range al.registry.ListAgentIDs() {
 		if agent, ok := al.registry.GetAgent(agentID); ok {
@@ -1165,6 +1197,12 @@ func (al *AgentLoop) runLLMIteration(
 				"target_channel": al.targetReasoningChannelID(opts.Channel),
 				"channel":        opts.Channel,
 			})
+
+		// Update token statistics for current session
+		if response.Usage != nil {
+			al.updateTokenStats(activeModel, response.Usage.PromptTokens, response.Usage.CompletionTokens)
+		}
+
 		// Check if no tool calls - then check reasoning content if any
 		if len(response.ToolCalls) == 0 {
 			finalContent = response.Content
@@ -1871,7 +1909,9 @@ func (al *AgentLoop) handleCommandAsync(ctx context.Context, msg bus.InboundMess
 
 	response, handled := al.handleCommand(ctx, msg, agent, opts)
 	if !handled {
-		// Command not recognized or passed through, ignore
+		// Command not recognized or passed through (e.g., strict command with extra args)
+		// Process as normal message through the agent
+		al.processMessageAsync(ctx, msg)
 		return
 	}
 
@@ -1955,6 +1995,7 @@ func (al *AgentLoop) buildCommandsRuntime(agent *AgentInstance, opts *processOpt
 			return nil
 		},
 		CancelCurrentTask: al.CancelCurrentTask,
+		GetTokenStats:     al.getTokenStats,
 	}
 	if agent != nil {
 		rt.GetModelInfo = func() (string, string) {

pkg/commands/builtin.go

@@ -14,5 +14,6 @@ func BuiltinDefinitions() []Definition {
 		checkCommand(),
 		stopCommand(),
 		clearCommand(),
+		statsCommand(),
 	}
 }

pkg/commands/cmd_stats.go

@@ -0,0 +1,39 @@
+package commands
+
+import (
+	"context"
+	"fmt"
+)
+
+// statsCommand returns the definition for the /stats command
+func statsCommand() Definition {
+	return Definition{
+		Name:        "stats",
+		Description: "Show token usage statistics for current session",
+		Handler:     handleStats,
+		Strict:      true,
+	}
+}
+
+func handleStats(ctx context.Context, req Request, rt *Runtime) error {
+	if rt.GetTokenStats == nil {
+		return req.Reply("Token stats not available")
+	}
+
+	stats := rt.GetTokenStats()
+	if stats == nil {
+		return req.Reply("No token usage data for current session")
+	}
+
+	return req.Reply(fmt.Sprintf(`Token Stats (Current Session)
+Model: %s
+Prompt: %d
+Completion: %d
+Total: %d
+Calls: %d`,
+		stats.Model,
+		stats.PromptTokens,
+		stats.CompletionTokens,
+		stats.TotalTokens,
+		stats.CallCount))
+}

pkg/commands/runtime.go

@@ -2,6 +2,15 @@ package commands
 
 import "github.com/sipeed/picoclaw/pkg/config"
 
+// TokenStats represents token usage statistics for the current session
+type TokenStats struct {
+	Model            string
+	PromptTokens     int
+	CompletionTokens int
+	TotalTokens      int
+	CallCount        int
+}
+
 // Runtime provides runtime dependencies to command handlers. It is constructed
 // per-request by the agent loop so that per-request state (like session scope)
 // can coexist with long-lived callbacks (like GetModelInfo).
@@ -15,4 +24,5 @@ type Runtime struct {
 	SwitchChannel      func(value string) error
 	CancelCurrentTask  func() bool // Cancel the currently running task, returns true if a task was cancelled
 	ClearHistory       func() error
+	GetTokenStats      func() *TokenStats // Get token usage statistics for current session
 }

pkg/llmlog/stats.go

@@ -0,0 +1,204 @@
+package llmlog
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+)
+
+// TokenStats represents token usage statistics for a model
+type TokenStats struct {
+	Model            string
+	PromptTokens     int
+	CompletionTokens int
+	TotalTokens      int
+	CallCount        int
+	ErrorCount       int
+}
+
+// StatsResult represents the result of a stats query
+type StatsResult struct {
+	ByModel  map[string]*TokenStats
+	Total    *TokenStats
+	StartDay string
+	EndDay   string
+}
+
+// CalculateStats calculates token usage statistics from log files
+// If days is 0, it calculates all available logs
+// If modelFilter is empty, it includes all models
+// Supports filename formats: "2006-01-02.jsonl" and "llmcall_2006-01-02.jsonl"
+func CalculateStats(logDir string, days int, modelFilter string) (*StatsResult, error) {
+	result := &StatsResult{
+		ByModel: make(map[string]*TokenStats),
+		Total: &TokenStats{
+			Model: "Total",
+		},
+	}
+
+	now := time.Now()
+	var startDate time.Time
+	if days > 0 {
+		startDate = now.AddDate(0, 0, -days)
+		result.StartDay = startDate.Format("2006-01-02")
+	} else {
+		startDate = time.Time{} // zero time means all
+	}
+	result.EndDay = now.Format("2006-01-02")
+
+	// Find all log files
+	files, err := filepath.Glob(filepath.Join(logDir, "*.jsonl"))
+	if err != nil {
+		return nil, fmt.Errorf("failed to list log files: %w", err)
+	}
+
+	for _, file := range files {
+		// Parse date from filename
+		// Supported formats: "2006-01-02.jsonl" and "llmcall_2006-01-02.jsonl"
+		filename := filepath.Base(file)
+		dateStr := strings.TrimSuffix(filename, ".jsonl")
+		
+		// Handle "llmcall_" prefix
+		if strings.HasPrefix(dateStr, "llmcall_") {
+			dateStr = strings.TrimPrefix(dateStr, "llmcall_")
+		}
+		
+		fileDate, err := time.Parse("2006-01-02", dateStr)
+		if err != nil {
+			continue // skip files with invalid names
+		}
+
+		// Check if file is within date range
+		if !startDate.IsZero() && fileDate.Before(startDate) {
+			continue
+		}
+
+		// Process file
+		if err := processLogFile(file, modelFilter, result); err != nil {
+			// Log error but continue processing other files
+			continue
+		}
+	}
+
+	// Sort models by total tokens for consistent output
+	return result, nil
+}
+
+func processLogFile(filePath string, modelFilter string, result *StatsResult) error {
+	file, err := os.Open(filePath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	decoder := json.NewDecoder(file)
+	for decoder.More() {
+		var record CallRecord
+		if err := decoder.Decode(&record); err != nil {
+			continue // skip malformed records
+		}
+
+		// Filter by model if specified
+		if modelFilter != "" && record.Model != modelFilter {
+			continue
+		}
+
+		// Get or create stats for this model
+		stats, exists := result.ByModel[record.Model]
+		if !exists {
+			stats = &TokenStats{Model: record.Model}
+			result.ByModel[record.Model] = stats
+		}
+
+		// Update stats
+		stats.PromptTokens += record.PromptTokens
+		stats.CompletionTokens += record.CompletionTokens
+		stats.TotalTokens += record.TotalTokens
+		stats.CallCount++
+		if record.Error != "" {
+			stats.ErrorCount++
+		}
+
+		// Update totals
+		result.Total.PromptTokens += record.PromptTokens
+		result.Total.CompletionTokens += record.CompletionTokens
+		result.Total.TotalTokens += record.TotalTokens
+		result.Total.CallCount++
+		if record.Error != "" {
+			result.Total.ErrorCount++
+		}
+	}
+
+	return nil
+}
+
+// FormatStatsTable formats the stats result as a table string
+func FormatStatsTable(result *StatsResult) string {
+	if len(result.ByModel) == 0 {
+		return "📊 no stats data found"
+	}
+
+	var sb strings.Builder
+
+	if result.StartDay != "" {
+		sb.WriteString(fmt.Sprintf("📊 Token Count (%s ~ %s)\n\n", result.StartDay, result.EndDay))
+	} else {
+		sb.WriteString(fmt.Sprintf("📊 Token Count (All，Until %s)\n\n", result.EndDay))
+	}
+
+	// Sort models by total tokens descending
+	models := make([]string, 0, len(result.ByModel))
+	for model := range result.ByModel {
+		models = append(models, model)
+	}
+	sort.Slice(models, func(i, j int) bool {
+		return result.ByModel[models[i]].TotalTokens > result.ByModel[models[j]].TotalTokens
+	})
+
+	// Table header
+	sb.WriteString("┌──────────────────────┬──────────────┬─────────────────┬──────────────┬──────────┐\n")
+	sb.WriteString("│ Model                │ Prompt Tokens│Completion Tokens│ Total Tokens │Call Count│\n")
+	sb.WriteString("├──────────────────────┼──────────────┼─────────────────┼──────────────┼──────────┤\n")
+
+	// Table rows
+	for _, model := range models {
+		stats := result.ByModel[model]
+		// Truncate model name if too long
+		displayModel := model
+		if len(displayModel) > 20 {
+			displayModel = displayModel[:17] + "..."
+		}
+		sb.WriteString(fmt.Sprintf("│ %-20s │ %12d │ %15d │ %12d │ %8d │\n",
+			displayModel, stats.PromptTokens, stats.CompletionTokens, stats.TotalTokens, stats.CallCount))
+	}
+
+	// Total row
+	sb.WriteString("├──────────────────────┼──────────────┼─────────────────┼──────────────┼──────────┤\n")
+	sb.WriteString(fmt.Sprintf("│ %-20s │ %12d │ %15d │ %12d │ %8d │\n",
+		"Total", result.Total.PromptTokens, result.Total.CompletionTokens, result.Total.TotalTokens, result.Total.CallCount))
+	sb.WriteString("└──────────────────────┴──────────────┴─────────────────┴──────────────┴──────────┘\n")
+
+	return sb.String()
+}
+
+// FormatSimpleStats formats stats for a single model (used in runtime /stats command)
+func FormatSimpleStats(stats *TokenStats) string {
+	var sb strings.Builder
+
+	sb.WriteString(fmt.Sprintf("📊 Token Stats (Current Session)\n"))
+	sb.WriteString(fmt.Sprintf("Model: %s\n", stats.Model))
+	sb.WriteString("┌─────────────────────┬───────────┐\n")
+	sb.WriteString("│ Metric              │ Value     │\n")
+	sb.WriteString("├─────────────────────┼───────────┤\n")
+	sb.WriteString(fmt.Sprintf("│ %-19s │ %9d │\n", "Prompt Tokens", stats.PromptTokens))
+	sb.WriteString(fmt.Sprintf("│ %-19s │ %9d │\n", "Completion Tokens", stats.CompletionTokens))
+	sb.WriteString(fmt.Sprintf("│ %-19s │ %9d │\n", "Total Tokens", stats.TotalTokens))
+	sb.WriteString(fmt.Sprintf("│ %-19s │ %9d │\n", "Call Count", stats.CallCount))
+	sb.WriteString("└─────────────────────┴───────────┘\n")
+
+	return sb.String()
+}

pkg/llmlog/types.go

@@ -18,7 +18,9 @@ type CallRecord struct {
 	Messages         []Message     `json:"messages"`
 	Response         string        `json:"response"`
 	Duration         time.Duration `json:"duration"`
-	TokensUsed  int           `json:"tokens_used,omitempty"`
+	PromptTokens     int           `json:"prompt_tokens,omitempty"`
+	CompletionTokens int           `json:"completion_tokens,omitempty"`
+	TotalTokens      int           `json:"total_tokens,omitempty"`
 	Error            string        `json:"error,omitempty"`
 	IsStreaming      bool          `json:"is_streaming"`
 }

pkg/providers/logging_provider.go

@@ -66,7 +66,9 @@ func (p *LoggingProvider) Chat(
 	} else {
 		record.Response = resp.Content
 		if resp.Usage != nil {
-			record.TokensUsed = resp.Usage.TotalTokens
+			record.PromptTokens = resp.Usage.PromptTokens
+			record.CompletionTokens = resp.Usage.CompletionTokens
+			record.TotalTokens = resp.Usage.TotalTokens
 		}
 	}