diff --git a/engine.go b/engine.go
index 9d64e39..f3de816 100644
--- a/engine.go
+++ b/engine.go
@@ -179,15 +179,14 @@ func (e *Engine) SavePendingSummary(name, text string) error {
 	return os.WriteFile(e.pendingPath(name), []byte(t+"\n"), 0o644)
 }
 
-// autoSummary 在没有任何人工摘要时，依据本次改动自动生成一句话摘要（仅本地记录用）。
-func (e *Engine) autoSummary(repoPath string) string {
+// statusFiles 返回工作区相对改动文件列表（用于自动摘要；须在 git add 之前调用）。
+func (e *Engine) statusFiles(repoPath string) []string {
 	out, err := gitRun(repoPath, 15*time.Second, "status", "--porcelain")
 	if err != nil {
-		return "自动提交"
+		return nil
 	}
-	lines := strings.Split(strings.TrimSpace(out), "\n")
 	var files []string
-	for _, ln := range lines {
+	for _, ln := range strings.Split(strings.TrimSpace(out), "\n") {
 		ln = strings.TrimSpace(ln)
 		if ln == "" {
 			continue
@@ -201,6 +200,12 @@ func (e *Engine) autoSummary(repoPath string) string {
 			files = append(files, p)
 		}
 	}
+	return files
+}
+
+// autoSummary 在没有任何人工摘要时，依据本次改动自动生成一句话摘要（仅本地记录用）。
+// files 须为提交前的改动文件列表（见 statusFiles）。
+func (e *Engine) autoSummary(files []string) string {
 	if len(files) == 0 {
 		return "自动提交（无改动文件）"
 	}
@@ -728,6 +733,10 @@ func (e *Engine) syncOnce(s *repoState, trigger string) {
 			if pend != "" {
 				cmsg = pend
 			}
+			var autoFiles []string
+			if pend == "" {
+				autoFiles = e.statusFiles(cfg.RepoPath)
+			}
 			if _, cerr := gitRun(cfg.RepoPath, 120*time.Second, "commit", "-m", cmsg); cerr != nil {
 				e.setFail(s, "自动提交失败: "+cerr.Error())
 				return
@@ -735,7 +744,7 @@ func (e *Engine) syncOnce(s *repoState, trigger string) {
 			if sha, serr := gitRun(cfg.RepoPath, 10*time.Second, "rev-parse", "--short", "HEAD"); serr == nil {
 				sum := cmsg
 				if pend == "" {
-					sum = e.autoSummary(cfg.RepoPath)
+					sum = e.autoSummary(autoFiles)
 				}
 				e.RecordCommit(s.cfg.Name, sha, sum)
 			}