diff --git a/docs b/docs
index 18dc676..de2f19d 160000
--- a/docs
+++ b/docs
@@ -1 +1 @@
-Subproject commit 18dc676a5f6d84a4c8a0497b3205651de7f634e7
+Subproject commit de2f19d644b8f971390a5886ff9a2ad9cb994a41
diff --git a/internal/ai/rag/index_retrieve_helpers_test.go b/internal/ai/rag/index_retrieve_helpers_test.go
new file mode 100644
index 0000000..bd2bbe5
--- /dev/null
+++ b/internal/ai/rag/index_retrieve_helpers_test.go
@@ -0,0 +1,91 @@
+package rag
+
+import (
+	"strings"
+	"testing"
+
+	"cs-agent/internal/models"
+)
+
+func TestBuildFAQChunkContent(t *testing.T) {
+	faq := &models.KnowledgeFAQ{
+		Question:         "如何退款",
+		SimilarQuestions: `["退款怎么申请","申请售后"]`,
+		Answer:           "在订单页发起退款。",
+	}
+
+	content := buildFAQChunkContent(faq)
+	if !strings.Contains(content, "问题：如何退款") {
+		t.Fatalf("expected question in content, got %q", content)
+	}
+	if !strings.Contains(content, "相似问：退款怎么申请；申请售后") {
+		t.Fatalf("expected similar questions in content, got %q", content)
+	}
+	if !strings.Contains(content, "回答：在订单页发起退款。") {
+		t.Fatalf("expected answer in content, got %q", content)
+	}
+}
+
+func TestBuildFAQChunkModel(t *testing.T) {
+	knowledgeBase := &models.KnowledgeBase{ID: 11}
+	faq := &models.KnowledgeFAQ{ID: 22, Question: "如何退款"}
+
+	chunk, chunkID := buildFAQChunkModel(knowledgeBase, faq, "问题：如何退款\n回答：在订单页发起退款。")
+	if chunkID == "" {
+		t.Fatalf("expected chunk id")
+	}
+	if chunk.KnowledgeBaseID != 11 || chunk.FaqID != 22 {
+		t.Fatalf("unexpected chunk identity: %#v", chunk)
+	}
+	if chunk.VectorID != chunkID {
+		t.Fatalf("expected vector id to match chunk id")
+	}
+	if chunk.Title != "如何退款" {
+		t.Fatalf("unexpected title: %q", chunk.Title)
+	}
+}
+
+func TestNormalizeContextResultsMergesAndDedupes(t *testing.T) {
+	results := normalizeContextResults([]RetrieveResult{
+		{DocumentID: 1, ChunkNo: 1, SectionPath: "A", Content: "第一段", Score: 0.7},
+		{DocumentID: 1, ChunkNo: 2, SectionPath: "A", Content: "第二段", Score: 0.9},
+		{DocumentID: 1, ChunkNo: 3, SectionPath: "A", Content: "第三段", Score: 0.6},
+		{DocumentID: 2, ChunkNo: 1, Title: "标题", Content: "独立段", Score: 0.5},
+		{FaqID: 9, FaqQuestion: "FAQ", Content: "FAQ内容", Score: 0.8},
+		{FaqID: 9, FaqQuestion: "FAQ", Content: "FAQ重复", Score: 0.7},
+	})
+
+	if len(results) != 3 {
+		t.Fatalf("expected 3 normalized results, got %d", len(results))
+	}
+	if !strings.Contains(results[0].Content, "第一段\n第二段") {
+		t.Fatalf("expected adjacent document chunks to merge, got %q", results[0].Content)
+	}
+	if results[0].Score != 0.9 {
+		t.Fatalf("expected merged score to keep max score, got %v", results[0].Score)
+	}
+	if results[1].Content != "独立段" {
+		t.Fatalf("expected section duplicates to be removed after merge, got %q", results[1].Content)
+	}
+}
+
+func TestBuildContextChunkText(t *testing.T) {
+	faqText := buildContextChunkText(RetrieveResult{
+		FaqID:       1,
+		FaqQuestion: "如何退款",
+		Content:     "在订单页发起退款。",
+	})
+	if !strings.Contains(faqText, "【FAQ：如何退款】") {
+		t.Fatalf("unexpected faq context text: %q", faqText)
+	}
+
+	docText := buildContextChunkText(RetrieveResult{
+		DocumentID:    2,
+		DocumentTitle: "退款文档",
+		SectionPath:   "售后/退款",
+		Content:       "文档内容",
+	})
+	if !strings.Contains(docText, "【文档：退款文档｜章节：售后/退款】") {
+		t.Fatalf("unexpected document context text: %q", docText)
+	}
+}
diff --git a/internal/ai/runtime/reply_helpers_test.go b/internal/ai/runtime/reply_helpers_test.go
new file mode 100644
index 0000000..803b381
--- /dev/null
+++ b/internal/ai/runtime/reply_helpers_test.go
@@ -0,0 +1,92 @@
+package runtime
+
+import (
+	"strings"
+	"testing"
+
+	"cs-agent/internal/pkg/toolx"
+)
+
+func TestSummaryPrimaryToolCodePrefersToolSearchTarget(t *testing.T) {
+	summary := &Summary{
+		InvokedToolCodes: []string{toolx.BuiltinToolSearch.Code},
+		TraceData: `{
+			"toolSearch": {
+				"items": [
+					{"targetToolCode":"mcp/server/tool_a"}
+				]
+			}
+		}`,
+	}
+
+	if got := summaryPrimaryToolCode(summary); got != "mcp/server/tool_a" {
+		t.Fatalf("unexpected primary tool code: %q", got)
+	}
+}
+
+func TestToRunLogFinalAction(t *testing.T) {
+	if got := toRunLogFinalAction(&Summary{PlannedSkillCode: "refund", ReplyText: "ok"}); got != "skill" {
+		t.Fatalf("expected skill final action, got %q", got)
+	}
+
+	graphSummary := &Summary{
+		ReplyText: "ok",
+		TraceData: `{
+			"graphTools": {
+				"items": [
+					{"toolCode":"` + toolx.GraphAnalyzeConversation.Code + `"}
+				]
+			}
+		}`,
+	}
+	if got := toRunLogFinalAction(graphSummary); got != "graph" {
+		t.Fatalf("expected graph final action, got %q", got)
+	}
+
+	if got := toRunLogFinalAction(&Summary{Status: "fallback"}); got != "fallback" {
+		t.Fatalf("expected fallback final action, got %q", got)
+	}
+}
+
+func TestExtractInterruptMessageAndCheckpointError(t *testing.T) {
+	if got := extractInterruptMessage(`{"message":"请补充订单号"}`); got != "请补充订单号" {
+		t.Fatalf("unexpected interrupt message: %q", got)
+	}
+	if got := extractInterruptMessage("not-json"); got != "" {
+		t.Fatalf("expected empty message for invalid json, got %q", got)
+	}
+
+	err := fakeErr("Failed to load from checkpoint: record does not exist")
+	if !isCheckpointMissingError(err) {
+		t.Fatalf("expected checkpoint missing error to be detected")
+	}
+	if isCheckpointMissingError(fakeErr("other error")) {
+		t.Fatalf("expected unrelated error to be ignored")
+	}
+}
+
+func TestGraphPlanReason(t *testing.T) {
+	summary := &Summary{
+		TraceData: `{
+			"graphTools": {
+				"items": [
+					{
+						"toolCode":"` + toolx.GraphTriageServiceRequest.Code + `",
+						"recommendedAction":"create_ticket",
+						"ticketDraftReady": true
+					}
+				]
+			}
+		}`,
+	}
+	got := graphPlanReason(summary)
+	if !strings.Contains(got, "create_ticket") || !strings.Contains(got, "ready ticket draft") {
+		t.Fatalf("unexpected graph plan reason: %q", got)
+	}
+}
+
+type fakeErr string
+
+func (e fakeErr) Error() string {
+	return string(e)
+}