diff --git a/internal/handler/agent_progress_callback_test.go b/internal/handler/agent_progress_callback_test.go
index 8c2b0da5..ea2bd69e 100644
--- a/internal/handler/agent_progress_callback_test.go
+++ b/internal/handler/agent_progress_callback_test.go
@@ -3,7 +3,6 @@ package handler
 import (
 	"context"
 	"fmt"
-	"os"
 	"path/filepath"
 	"strings"
 	"sync"
@@ -86,6 +85,7 @@ func TestCreateProgressCallback_HidesInternalEinoDiagnostics(t *testing.T) {
 	if err != nil {
 		t.Fatalf("NewDB: %v", err)
 	}
+	t.Cleanup(func() { _ = db.Close() })
 	conv, err := db.CreateConversation("diag-hidden", database.ConversationCreateMeta{})
 	if err != nil {
 		t.Fatalf("CreateConversation: %v", err)
@@ -133,6 +133,7 @@ func TestCreateProgressCallback_PersistsRunningResponseBeforeDone(t *testing.T)
 	if err != nil {
 		t.Fatalf("NewDB: %v", err)
 	}
+	t.Cleanup(func() { _ = db.Close() })
 	conv, err := db.CreateConversation("refresh-running", database.ConversationCreateMeta{})
 	if err != nil {
 		t.Fatalf("CreateConversation: %v", err)
@@ -178,8 +179,8 @@ func TestCreateProgressCallback_FlushesReasoningOnDone(t *testing.T) {
 	if err != nil {
 		t.Fatalf("NewDB: %v", err)
 	}
-	defer os.RemoveAll(tmp)
 
+	t.Cleanup(func() { _ = db.Close() })
 	conv, err := db.CreateConversation("test", database.ConversationCreateMeta{})
 	if err != nil {
 		t.Fatalf("CreateConversation: %v", err)
diff --git a/internal/handler/hitl.go b/internal/handler/hitl.go
index c136499d..44b8b4a4 100644
--- a/internal/handler/hitl.go
+++ b/internal/handler/hitl.go
@@ -153,7 +153,8 @@ SELECT msg.id, msg.conversation_id,
            SELECT MIN(later.created_at)
            FROM messages later
            WHERE later.conversation_id = msg.conversation_id
-             AND later.created_at > msg.created_at
+             AND (later.created_at > msg.created_at
+                  OR (later.created_at = msg.created_at AND later.rowid > msg.rowid))
        ), (
            SELECT MAX(pd.created_at)
            FROM process_details pd
@@ -177,7 +178,8 @@ WHERE msg.role = 'assistant'
       OR EXISTS (
           SELECT 1 FROM messages later
           WHERE later.conversation_id = msg.conversation_id
-            AND later.created_at > msg.created_at
+            AND (later.created_at > msg.created_at
+                  OR (later.created_at = msg.created_at AND later.rowid > msg.rowid))
       )
   )`)
 	if err != nil {
diff --git a/internal/handler/hitl_context_test.go b/internal/handler/hitl_context_test.go
index cdf3870c..baa538e9 100644
--- a/internal/handler/hitl_context_test.go
+++ b/internal/handler/hitl_context_test.go
@@ -1,7 +1,6 @@
 package handler
 
 import (
-	"os"
 	"path/filepath"
 	"testing"
 
@@ -16,7 +15,7 @@ func TestEnrichHitlApprovalPayload(t *testing.T) {
 	if err != nil {
 		t.Fatalf("db: %v", err)
 	}
-	defer os.RemoveAll(tmp)
+	t.Cleanup(func() { _ = db.Close() })
 
 	conv, err := db.CreateConversation("hitl ctx", database.ConversationCreateMeta{})
 	if err != nil {
diff --git a/internal/handler/hitl_restart_test.go b/internal/handler/hitl_restart_test.go
index f5ec1475..00df54ee 100644
--- a/internal/handler/hitl_restart_test.go
+++ b/internal/handler/hitl_restart_test.go
@@ -98,9 +98,16 @@ func TestEnsureSchemaFinalizesOnlyHistoricalPlaceholdersWithTerminalEvidence(t *
 	if err != nil {
 		t.Fatalf("create superseded placeholder: %v", err)
 	}
-	if _, err := db.AddMessage(supersededConversation.ID, "user", "继续", nil); err != nil {
+	later, err := db.AddMessage(supersededConversation.ID, "user", "继续", nil)
+	if err != nil {
 		t.Fatalf("create later message: %v", err)
 	}
+	// Coarse clocks (notably Windows) can give consecutive messages the same
+	// timestamp. Match the message ordering used by GetMessages: time, then rowid.
+	if _, err := db.Exec(`UPDATE messages SET created_at =
+		(SELECT created_at FROM messages WHERE id = ?) WHERE id = ?`, superseded.ID, later.ID); err != nil {
+		t.Fatalf("give consecutive messages equal timestamps: %v", err)
+	}
 
 	timeoutConversation, err := db.CreateConversation("timeout placeholder", database.ConversationCreateMeta{})
 	if err != nil {
@@ -136,10 +143,18 @@ func TestEnsureSchemaFinalizesOnlyHistoricalPlaceholdersWithTerminalEvidence(t *
 	if err != nil {
 		t.Fatalf("create active conversation: %v", err)
 	}
+	earlier, err := db.AddMessage(activeConversation.ID, "user", "开始", nil)
+	if err != nil {
+		t.Fatalf("create preceding message: %v", err)
+	}
 	potentiallyActive, err := db.AddMessage(activeConversation.ID, "assistant", "处理中...", nil)
 	if err != nil {
 		t.Fatalf("create potentially active placeholder: %v", err)
 	}
+	if _, err := db.Exec(`UPDATE messages SET created_at =
+		(SELECT created_at FROM messages WHERE id = ?) WHERE id = ?`, potentiallyActive.ID, earlier.ID); err != nil {
+		t.Fatalf("give preceding message equal timestamp: %v", err)
+	}
 
 	if err := manager.EnsureSchema(); err != nil {
 		t.Fatalf("reconcile historical placeholders: %v", err)
diff --git a/internal/handler/tool_guard_test.go b/internal/handler/tool_guard_test.go
index 570c659c..e2d77cd2 100644
--- a/internal/handler/tool_guard_test.go
+++ b/internal/handler/tool_guard_test.go
@@ -50,6 +50,10 @@ func toolGuardRequest(t *testing.T, handler gin.HandlerFunc, body interface{}) *
 
 func TestToolGuardSavePersistsAndAppliesWithoutChangingHITL(t *testing.T) {
 	h := newToolGuardTestHandler(t)
+	before, err := os.Stat(h.configPath)
+	if err != nil {
+		t.Fatal(err)
+	}
 	cfg := toolguard.DefaultConfig()
 	cfg.Rules[0].Message = "识别到 {match}，禁止攻击政府网站，请检查目标。"
 	w := toolGuardRequest(t, h.UpdateToolGuard, cfg)
@@ -68,7 +72,7 @@ func TestToolGuardSavePersistsAndAppliesWithoutChangingHITL(t *testing.T) {
 	}
 	info, _ := os.Stat(h.configPath)
 	data, _ := os.ReadFile(h.configPath)
-	if info.Mode().Perm() != 0600 || !strings.Contains(string(data), "# keep this comment") {
+	if info.Mode().Perm() != before.Mode().Perm() || !strings.Contains(string(data), "# keep this comment") {
 		t.Fatal("file permissions or comments were lost")
 	}
 	match := h.toolGuard.Check("scan", map[string]interface{}{"target": "agency.gov.cn"})