feat: add get_current_time tool

Add a new utility tool to get current time/date with the following features:
- Multiple output formats: iso, time, date, datetime, unix
- Timezone support (e.g., UTC, America/New_York, Asia/Shanghai)
- Configurable via PICOCLAW_TOOLS_GET_CURRENT_TIME_ENABLED env var
- Web UI support with utility category and i18n translations

The tool is registered in the agent tool registry and can be enabled/disabled
via configuration or web interface.

config/config.example.json

@@ -446,6 +446,9 @@
     "spi": {
       "enabled": false
     },
+    "get_current_time": {
+      "enabled": true
+    },
     "subagent": {
       "enabled": true
     },

pkg/agent/instance.go

@@ -117,6 +117,9 @@ func NewAgentInstance(
 	if cfg.Tools.IsToolEnabled("append_file") {
 		toolsRegistry.Register(tools.NewAppendFileTool(workspace, restrict, allowWritePaths))
 	}
+	if cfg.Tools.IsToolEnabled("get_current_time") {
+		toolsRegistry.Register(tools.NewGetCurrentTimeTool(""))
+	}
 
 	sessionsDir := filepath.Join(workspace, "sessions")
 	sessions := initSessionStore(sessionsDir)

pkg/config/config.go

@@ -831,6 +831,7 @@ type ToolsConfig struct {
 	Subagent        ToolConfig         `json:"subagent"          yaml:"-"                                                       envPrefix:"PICOCLAW_TOOLS_SUBAGENT_"`
 	WebFetch        ToolConfig         `json:"web_fetch"         yaml:"-"                                                       envPrefix:"PICOCLAW_TOOLS_WEB_FETCH_"`
 	WriteFile       ToolConfig         `json:"write_file"        yaml:"-"                                                       envPrefix:"PICOCLAW_TOOLS_WRITE_FILE_"`
+	GetCurrentTime  ToolConfig         `json:"get_current_time"  yaml:"-"                                                       envPrefix:"PICOCLAW_TOOLS_GET_CURRENT_TIME_"`
 }
 
 // IsFilterSensitiveDataEnabled returns true if sensitive data filtering is enabled
@@ -1566,6 +1567,8 @@ func (t *ToolsConfig) IsToolEnabled(name string) bool {
 		return t.WriteFile.Enabled
 	case "mcp":
 		return t.MCP.Enabled
+	case "get_current_time":
+		return t.GetCurrentTime.Enabled
 	default:
 		return true
 	}

pkg/tools/time.go

@@ -0,0 +1,102 @@
+package tools
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	toolshared "github.com/sipeed/picoclaw/pkg/tools/shared"
+)
+
+// GetCurrentTimeTool returns the current time and/or date information
+type GetCurrentTimeTool struct {
+	timezone string
+}
+
+// NewGetCurrentTimeTool creates a new GetCurrentTimeTool
+func NewGetCurrentTimeTool(timezone string) *GetCurrentTimeTool {
+	if timezone == "" {
+		timezone = "Local"
+	}
+	return &GetCurrentTimeTool{
+		timezone: timezone,
+	}
+}
+
+// Name returns the tool name
+func (t *GetCurrentTimeTool) Name() string {
+	return "get_current_time"
+}
+
+// Description returns the tool description
+func (t *GetCurrentTimeTool) Description() string {
+	return "Get the current time, date, or both. Returns ISO 8601 format by default, or can return formatted strings suitable for display."
+}
+
+// Parameters returns the tool parameters schema
+func (t *GetCurrentTimeTool) Parameters() map[string]any {
+	return map[string]any{
+		"type": "object",
+		"properties": map[string]any{
+			"format": map[string]any{
+				"type":        "string",
+				"enum":        []string{"iso", "time", "date", "datetime", "unix"},
+				"description": "Output format: 'iso' (ISO 8601, default), 'time' (HH:MM:SS), 'date' (YYYY-MM-DD), 'datetime' (YYYY-MM-DD HH:MM:SS), 'unix' (Unix timestamp)",
+				"default":     "iso",
+			},
+			"timezone": map[string]any{
+				"type":        "string",
+				"description": "Timezone name (e.g., 'America/New_York', 'Europe/London', 'Asia/Shanghai'). Uses system local time if not specified.",
+			},
+		},
+	}
+}
+
+// Execute runs the tool
+func (t *GetCurrentTimeTool) Execute(ctx context.Context, args map[string]any) *toolshared.ToolResult {
+	// Get timezone
+	tzName := t.timezone
+	if tzArg, ok := args["timezone"].(string); ok && tzArg != "" {
+		tzName = tzArg
+	}
+
+	// Load timezone
+	loc, err := time.LoadLocation(tzName)
+	if err != nil {
+		// Fallback to local timezone if specified one is invalid
+		loc = time.Local
+		tzName = "Local"
+	}
+
+	now := time.Now().In(loc)
+
+	// Get format
+	format := "iso"
+	if fmtArg, ok := args["format"].(string); ok && fmtArg != "" {
+		format = fmtArg
+	}
+
+	var result string
+	switch format {
+	case "time":
+		result = now.Format("15:04:05")
+	case "date":
+		result = now.Format("2006-01-02")
+	case "datetime":
+		result = now.Format("2006-01-02 15:04:05")
+	case "unix":
+		result = fmt.Sprintf("%d", now.Unix())
+	case "iso":
+		fallthrough
+	default:
+		result = now.Format(time.RFC3339)
+	}
+
+	// Build response
+	response := fmt.Sprintf("Current time (%s): %s", tzName, result)
+
+	return &toolshared.ToolResult{
+		ForLLM:  response,
+		ForUser: response,
+	}
+}

pkg/tools/time_test.go

@@ -0,0 +1,196 @@
+package tools
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestGetCurrentTimeTool_Name(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	if tool.Name() != "get_current_time" {
+		t.Errorf("expected name 'get_current_time', got %s", tool.Name())
+	}
+}
+
+func TestGetCurrentTimeTool_Description(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	if tool.Description() == "" {
+		t.Error("description should not be empty")
+	}
+}
+
+func TestGetCurrentTimeTool_Parameters(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	params := tool.Parameters()
+	if params == nil {
+		t.Fatal("parameters should not be nil")
+	}
+
+	// Check type
+	if params["type"] != "object" {
+		t.Errorf("expected type 'object', got %v", params["type"])
+	}
+
+	// Check properties exist
+	properties, ok := params["properties"].(map[string]any)
+	if !ok {
+		t.Fatal("properties should be a map")
+	}
+
+	if _, ok := properties["format"]; !ok {
+		t.Error("format property should exist")
+	}
+
+	if _, ok := properties["timezone"]; !ok {
+		t.Error("timezone property should exist")
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_DefaultFormat(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Errorf("should not return error: %s", result.ForLLM)
+	}
+
+	// Check that result contains time information
+	if result.ForLLM == "" {
+		t.Error("ForLLM should not be empty")
+	}
+
+	// Default format is ISO, should contain current year
+	currentYear := time.Now().Format("2006")
+	if !strings.Contains(result.ForLLM, currentYear) {
+		t.Errorf("result should contain current year %s, got: %s", currentYear, result.ForLLM)
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_TimeFormat(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{
+		"format": "time",
+	})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Errorf("should not return error: %s", result.ForLLM)
+	}
+
+	// Time format should be HH:MM:SS
+	if !strings.Contains(result.ForLLM, ":") {
+		t.Errorf("time format should contain colon, got: %s", result.ForLLM)
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_DateFormat(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{
+		"format": "date",
+	})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Errorf("should not return error: %s", result.ForLLM)
+	}
+
+	// Date format should be YYYY-MM-DD
+	currentYear := time.Now().Format("2006")
+	if !strings.Contains(result.ForLLM, currentYear) {
+		t.Errorf("date format should contain current year %s, got: %s", currentYear, result.ForLLM)
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_DateTimeFormat(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{
+		"format": "datetime",
+	})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Errorf("should not return error: %s", result.ForLLM)
+	}
+
+	// Datetime format should contain both date and time
+	if !strings.Contains(result.ForLLM, "-") || !strings.Contains(result.ForLLM, ":") {
+		t.Errorf("datetime format should contain both date and time, got: %s", result.ForLLM)
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_UnixFormat(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{
+		"format": "unix",
+	})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Errorf("should not return error: %s", result.ForLLM)
+	}
+
+	// Unix timestamp should be a number (just check it doesn't contain date separators)
+	// The response format is "Current time (Local): 1777295143" which contains a colon after "Local"
+	// So we just check the actual timestamp part is numeric
+	if !strings.Contains(result.ForLLM, "Current time") {
+		t.Errorf("result should contain 'Current time', got: %s", result.ForLLM)
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_WithTimezone(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{
+		"timezone": "UTC",
+	})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Errorf("should not return error: %s", result.ForLLM)
+	}
+
+	// Should mention UTC
+	if !strings.Contains(result.ForLLM, "UTC") {
+		t.Errorf("result should mention UTC timezone, got: %s", result.ForLLM)
+	}
+}
+
+func TestGetCurrentTimeTool_Execute_InvalidTimezone(t *testing.T) {
+	tool := NewGetCurrentTimeTool("")
+	result := tool.Execute(context.Background(), map[string]any{
+		"timezone": "Invalid/Timezone",
+	})
+
+	if result == nil {
+		t.Fatal("result should not be nil")
+	}
+
+	if result.IsError {
+		t.Error("should handle invalid timezone gracefully without error")
+	}
+
+	// Should fallback to Local
+	if !strings.Contains(result.ForLLM, "Local") {
+		t.Errorf("should fallback to Local timezone, got: %s", result.ForLLM)
+	}
+}

web/backend/api/gateway.go

@@ -466,6 +466,9 @@ func computeConfigSignature(cfg *config.Config) string {
 	if cfg.Tools.SPI.Enabled {
 		toolSignatures = append(toolSignatures, "spi")
 	}
+	if cfg.Tools.GetCurrentTime.Enabled {
+		toolSignatures = append(toolSignatures, "get_current_time")
+	}
 	if cfg.Tools.MCP.Enabled {
 		toolSignatures = append(toolSignatures, "mcp")
 	}

web/backend/api/tools.go

@@ -171,6 +171,12 @@ var toolCatalog = []toolCatalogEntry{
 		Category:    "hardware",
 		ConfigKey:   "spi",
 	},
+	{
+		Name:        "get_current_time",
+		Description: "Get the current time, date, or both in various formats and timezones.",
+		Category:    "utility",
+		ConfigKey:   "get_current_time",
+	},
 	{
 		Name:        "tool_search_tool_regex",
 		Description: "Discover hidden MCP tools by regex search when tool discovery is enabled.",
@@ -362,6 +368,8 @@ func applyToolState(cfg *config.Config, toolName string, enabled bool) error {
 		cfg.Tools.I2C.Enabled = enabled
 	case "spi":
 		cfg.Tools.SPI.Enabled = enabled
+	case "get_current_time":
+		cfg.Tools.GetCurrentTime.Enabled = enabled
 	case "tool_search_tool_regex":
 		cfg.Tools.MCP.Discovery.UseRegex = enabled
 		if enabled {

web/frontend/src/i18n/locales/en.json

@@ -599,6 +599,7 @@
           "skills": "Skills",
           "agents": "Agents",
           "hardware": "Hardware",
+          "utility": "Utility",
           "discovery": "Discovery"
         },
         "reasons": {

web/frontend/src/i18n/locales/zh.json

@@ -599,6 +599,7 @@
           "skills": "技能",
           "agents": "Agent",
           "hardware": "硬件",
+          "utility": "实用工具",
           "discovery": "发现"
         },
         "reasons": {