diff --git a/internal/project/user_verbatim_anchor.go b/internal/project/user_verbatim_anchor.go
new file mode 100644
index 00000000..bed7676f
--- /dev/null
+++ b/internal/project/user_verbatim_anchor.go
@@ -0,0 +1,170 @@
+package project
+
+import (
+	"fmt"
+	"strings"
+
+	"cyberstrike-ai/internal/database"
+
+	"github.com/cloudwego/eino/adk"
+	"github.com/cloudwego/eino/schema"
+)
+
+const (
+	// UserVerbatimSectionHeading 用户原文锚点可读标题（块内保留，供 Agent 阅读）。
+	UserVerbatimSectionHeading = "## 用户历史输入（原文保留，勿省略或改写）"
+
+	// UserVerbatimSectionStartMarker / EndMarker：HTML 注释边界，供程序化替换；对模型无指令语义。
+	UserVerbatimSectionStartMarker = "<!-- user-verbatim-start -->"
+	UserVerbatimSectionEndMarker   = "<!-- user-verbatim-end -->"
+)
+
+// ExtractUserContentsFromMessages 按时间顺序提取 user 角色消息的原文（跳过空白）。
+func ExtractUserContentsFromMessages(msgs []database.Message) []string {
+	out := make([]string, 0, len(msgs))
+	for i := range msgs {
+		if !strings.EqualFold(strings.TrimSpace(msgs[i].Role), "user") {
+			continue
+		}
+		content := strings.TrimSpace(msgs[i].Content)
+		if content == "" {
+			continue
+		}
+		out = append(out, content)
+	}
+	return out
+}
+
+// BuildUserVerbatimAnchorBlockFromMessages 从 messages 表行构建用户原文锚点块。
+// maxRunes: 0 = 不截断；>0 = 总 rune 上限（仍保留每一轮，仅对超长单条做尾部截断提示）。
+func BuildUserVerbatimAnchorBlockFromMessages(msgs []database.Message, maxRunes int) string {
+	return BuildUserVerbatimAnchorBlock(ExtractUserContentsFromMessages(msgs), maxRunes)
+}
+
+// BuildUserVerbatimAnchorBlock 将各轮用户原文格式化为 system prompt 锚点块。
+func BuildUserVerbatimAnchorBlock(userContents []string, maxRunes int) string {
+	if len(userContents) == 0 {
+		return ""
+	}
+	lines := make([]string, 0, len(userContents))
+	for _, content := range userContents {
+		content = strings.TrimSpace(content)
+		if content == "" {
+			continue
+		}
+		lines = append(lines, fmt.Sprintf("[第%d轮] %s", len(lines)+1, content))
+	}
+	if len(lines) == 0 {
+		return ""
+	}
+	body := strings.Join(lines, "\n")
+	if maxRunes > 0 {
+		body = capUserVerbatimBody(body, maxRunes)
+	}
+	return wrapUserVerbatimBlock(UserVerbatimSectionHeading + "\n\n" + body)
+}
+
+func capUserVerbatimBody(body string, maxRunes int) string {
+	rs := []rune(body)
+	if len(rs) <= maxRunes {
+		return body
+	}
+	suffix := "\n\n...(用户原文锚点已达配置上限，更早轮次可能被截断；完整原文见 messages 表)..."
+	suffixRunes := []rune(suffix)
+	keep := maxRunes - len(suffixRunes)
+	if keep <= 0 {
+		return string(rs[:maxRunes])
+	}
+	return string(rs[:keep]) + suffix
+}
+
+func wrapUserVerbatimBlock(content string) string {
+	content = strings.TrimSpace(content)
+	if content == "" {
+		return ""
+	}
+	return UserVerbatimSectionStartMarker + "\n" + content + "\n" + UserVerbatimSectionEndMarker + "\n"
+}
+
+// ReplaceUserVerbatimAnchorSection 用 freshBlock 替换 content 中已有的用户原文锚点段。
+func ReplaceUserVerbatimAnchorSection(content, freshBlock string) (string, bool) {
+	content = strings.TrimSpace(content)
+	freshBlock = strings.TrimSpace(freshBlock)
+	if freshBlock == "" {
+		return content, false
+	}
+	start, ok := userVerbatimSectionStart(content)
+	if !ok {
+		return content, false
+	}
+	end, ok := userVerbatimSectionEnd(content, start)
+	if !ok {
+		return content, false
+	}
+	return strings.TrimSpace(content[:start] + freshBlock + content[end:]), true
+}
+
+func userVerbatimSectionStart(content string) (int, bool) {
+	idx := strings.Index(content, UserVerbatimSectionStartMarker)
+	if idx < 0 {
+		return 0, false
+	}
+	return idx, true
+}
+
+func userVerbatimSectionEnd(content string, start int) (int, bool) {
+	if start < 0 || start >= len(content) {
+		return 0, false
+	}
+	tail := content[start:]
+	idx := strings.LastIndex(tail, UserVerbatimSectionEndMarker)
+	if idx < 0 {
+		return 0, false
+	}
+	return start + idx + len(UserVerbatimSectionEndMarker), true
+}
+
+// RefreshUserVerbatimAnchorInMessages 在 summarization 等压缩后，用 freshBlock 刷新 system 中的用户原文锚点。
+// 若尚无锚点段，则追加到首条 system 消息；若无 system 消息则在开头插入一条。
+func RefreshUserVerbatimAnchorInMessages(msgs []adk.Message, freshBlock string) []adk.Message {
+	freshBlock = strings.TrimSpace(freshBlock)
+	if freshBlock == "" || len(msgs) == 0 {
+		return msgs
+	}
+
+	out := make([]adk.Message, len(msgs))
+	changed := false
+	for i, msg := range msgs {
+		if msg == nil || msg.Role != schema.System {
+			out[i] = msg
+			continue
+		}
+		newContent, ok := ReplaceUserVerbatimAnchorSection(msg.Content, freshBlock)
+		if !ok {
+			out[i] = msg
+			continue
+		}
+		cloned := *msg
+		cloned.Content = newContent
+		out[i] = &cloned
+		changed = true
+	}
+
+	if changed {
+		return out
+	}
+
+	for i, msg := range msgs {
+		if msg == nil || msg.Role != schema.System {
+			continue
+		}
+		cloned := *msg
+		cloned.Content = AppendSystemPromptBlock(cloned.Content, freshBlock)
+		out[i] = &cloned
+		return out
+	}
+
+	prefix := make([]adk.Message, 0, len(msgs)+1)
+	prefix = append(prefix, schema.SystemMessage(freshBlock))
+	return append(prefix, msgs...)
+}
diff --git a/internal/project/user_verbatim_anchor_test.go b/internal/project/user_verbatim_anchor_test.go
new file mode 100644
index 00000000..2ace353f
--- /dev/null
+++ b/internal/project/user_verbatim_anchor_test.go
@@ -0,0 +1,96 @@
+package project
+
+import (
+	"strings"
+	"testing"
+
+	"cyberstrike-ai/internal/database"
+
+	"github.com/cloudwego/eino/adk"
+	"github.com/cloudwego/eino/schema"
+)
+
+func TestBuildUserVerbatimAnchorBlock_MultiTurn(t *testing.T) {
+	msgs := []database.Message{
+		{Role: "user", Content: "目标 https://a.com 仅测 /api"},
+		{Role: "assistant", Content: "好的"},
+		{Role: "user", Content: "用 admin:test 登录"},
+	}
+	block := BuildUserVerbatimAnchorBlockFromMessages(msgs, 0)
+	if block == "" {
+		t.Fatal("expected non-empty block")
+	}
+	if !strings.Contains(block, UserVerbatimSectionStartMarker) {
+		t.Error("missing start marker")
+	}
+	if !strings.Contains(block, "[第1轮]") || !strings.Contains(block, "https://a.com") {
+		t.Error("missing first user turn")
+	}
+	if !strings.Contains(block, "[第2轮]") || !strings.Contains(block, "admin:test") {
+		t.Error("missing second user turn")
+	}
+	if strings.Contains(block, "好的") {
+		t.Error("assistant content should not appear")
+	}
+}
+
+func TestReplaceUserVerbatimAnchorSection(t *testing.T) {
+	old := "prefix\n\n" + wrapUserVerbatimBlock("## old\n\n[第1轮] a") + "\nsuffix"
+	newBlock := wrapUserVerbatimBlock(UserVerbatimSectionHeading + "\n\n[第1轮] b\n[第2轮] c")
+	out, ok := ReplaceUserVerbatimAnchorSection(old, newBlock)
+	if !ok {
+		t.Fatal("expected replace ok")
+	}
+	if !strings.Contains(out, "[第2轮] c") {
+		t.Errorf("expected new block, got %q", out)
+	}
+	if !strings.HasPrefix(strings.TrimSpace(out), "prefix") {
+		t.Error("prefix should remain")
+	}
+	if !strings.Contains(out, "suffix") {
+		t.Error("suffix should remain")
+	}
+}
+
+func TestRefreshUserVerbatimAnchorInMessages_ReplaceExisting(t *testing.T) {
+	oldBlock := wrapUserVerbatimBlock(UserVerbatimSectionHeading + "\n\n[第1轮] old")
+	msgs := []adk.Message{
+		schema.SystemMessage("instr\n\n" + oldBlock),
+		schema.UserMessage("hi"),
+	}
+	newBlock := wrapUserVerbatimBlock(UserVerbatimSectionHeading + "\n\n[第1轮] new")
+	out := RefreshUserVerbatimAnchorInMessages(msgs, newBlock)
+	if len(out) != 2 {
+		t.Fatalf("message count: got %d", len(out))
+	}
+	if !strings.Contains(out[0].Content, "[第1轮] new") {
+		t.Errorf("system content: %q", out[0].Content)
+	}
+	if strings.Contains(out[0].Content, "[第1轮] old") {
+		t.Error("old anchor should be replaced")
+	}
+}
+
+func TestRefreshUserVerbatimAnchorInMessages_InsertWhenMissing(t *testing.T) {
+	msgs := []adk.Message{
+		schema.SystemMessage("base instruction"),
+		schema.UserMessage("hi"),
+	}
+	block := wrapUserVerbatimBlock(UserVerbatimSectionHeading + "\n\n[第1轮] anchor")
+	out := RefreshUserVerbatimAnchorInMessages(msgs, block)
+	if !strings.Contains(out[0].Content, "[第1轮] anchor") {
+		t.Errorf("expected appended anchor, got %q", out[0].Content)
+	}
+}
+
+func TestBuildUserVerbatimAnchorBlock_MaxRunes(t *testing.T) {
+	long := strings.Repeat("字", 200)
+	block := BuildUserVerbatimAnchorBlock([]string{long}, 50)
+	body := block
+	if idx := strings.Index(body, UserVerbatimSectionStartMarker); idx >= 0 {
+		body = strings.TrimPrefix(body[idx+len(UserVerbatimSectionStartMarker):], "\n")
+	}
+	if len([]rune(body)) > 120 {
+		t.Errorf("expected capped body, got %d runes", len([]rune(body)))
+	}
+}