feat: add preview support for ask_user tool

Author: voocel

internal/cron/cron.go

@@ -13,7 +13,6 @@ import (
 	"strconv"
 	"strings"
 	"sync"
-	"syscall"
 	"time"
 )
 
@@ -35,7 +34,7 @@ type Job struct {
 	Durable   bool   `json:"durable,omitempty"`
 
 	interval time.Duration // parsed interval (mutually exclusive with cronExpr)
-	cronExpr *CronExpr    // parsed cron expression
+	cronExpr *CronExpr     // parsed cron expression
 	nextFire time.Time
 }
 
@@ -67,8 +66,8 @@ type Store struct {
 
 	writeCh chan struct{} // capacity 1 — coalesces multiple write requests
 	closeCh chan struct{} // signals writer goroutine to stop
-	writeMu sync.Mutex   // serializes StartWriter/StopWriter calls
-	writing bool         // true while writer goroutine is running
+	writeMu sync.Mutex    // serializes StartWriter/StopWriter calls
+	writing bool          // true while writer goroutine is running
 }
 
 // NewStore creates an empty Store. Call SetConfigDir to enable durable storage.
@@ -609,14 +608,6 @@ func (s *Store) readLock(lockPath string) *lockData {
 	return &ld
 }
 
-// processAlive checks if a PID is alive by sending signal 0.
-func processAlive(pid int) bool {
-	if pid <= 0 {
-		return false
-	}
-	return syscall.Kill(pid, 0) == nil
-}
-
 // ---------------------------------------------------------------------------
 // Jitter — deterministic per-ID offset to avoid thundering herd
 // ---------------------------------------------------------------------------

internal/cron/process_alive_unix.go

@@ -0,0 +1,14 @@
+//go:build !windows
+
+package cron
+
+import "syscall"
+
+// processAlive checks whether the PID still exists on Unix-like systems.
+func processAlive(pid int) bool {
+	if pid <= 0 {
+		return false
+	}
+	err := syscall.Kill(pid, 0)
+	return err == nil || err == syscall.EPERM
+}

internal/cron/process_alive_windows.go

@@ -0,0 +1,23 @@
+//go:build windows
+
+package cron
+
+import "syscall"
+
+const processQueryLimitedInformation = 0x1000
+
+// processAlive checks whether the PID still exists on Windows.
+func processAlive(pid int) bool {
+	if pid <= 0 {
+		return false
+	}
+
+	handle, err := syscall.OpenProcess(processQueryLimitedInformation, false, uint32(pid))
+	if err == nil {
+		_ = syscall.CloseHandle(handle)
+		return true
+	}
+
+	// Access denied still means a process with that PID exists.
+	return err == syscall.ERROR_ACCESS_DENIED
+}

internal/tools/ask_user.go

@@ -11,10 +11,10 @@ import (
 	"github.com/voocel/agentcore/schema"
 )
 
-// AskUserResponse carries answers and optional user notes (from custom input).
+// AskUserResponse carries answers and optional user notes.
 type AskUserResponse struct {
 	Answers map[string]string // question text → answer
-	Notes   map[string]string // question text → custom note (only for "Type something")
+	Notes   map[string]string // question text → user note (from "Type something" or preview notes)
 }
 
 // AskUserHandler blocks until the user answers all questions.
@@ -33,6 +33,7 @@ type Question struct {
 type Option struct {
 	Label       string `json:"label"`
 	Description string `json:"description"`
+	Preview     string `json:"preview,omitempty"` // optional markdown preview content
 }
 
 // AskUserTool lets the LLM ask the user structured questions.
@@ -63,6 +64,7 @@ func (t *AskUserTool) Schema() map[string]any {
 	option := schema.Object(
 		schema.Property("label", schema.String("Display text (1-5 words)")).Required(),
 		schema.Property("description", schema.String("What this option means")).Required(),
+		schema.Property("preview", schema.String("Optional preview content (markdown) shown in a side panel when this option is focused")),
 	)
 	question := schema.Object(
 		schema.Property("question", schema.String("The complete question to ask")).Required(),
@@ -148,9 +150,16 @@ func formatAnswers(questions []Question, resp *AskUserResponse) string {
 			continue
 		}
 		entry := fmt.Sprintf("%q=%q", q.Question, answer)
-		if note, hasNote := resp.Notes[q.Question]; hasNote {
+		if note, hasNote := resp.Notes[q.Question]; hasNote && note != "" {
 			entry += " user notes: " + note
 		}
+		// Include preview content of the selected option for context.
+		for _, opt := range q.Options {
+			if opt.Label == answer && opt.Preview != "" {
+				entry += " preview: " + opt.Preview
+				break
+			}
+		}
 		parts = append(parts, entry)
 	}
 	return fmt.Sprintf("User has answered your questions: %s. You can now continue with the user's answers in mind.", strings.Join(parts, ", "))