diff --git a/api/internal/crawl/crawler/crawler.go b/api/internal/crawl/crawler/crawler.go
index 31cabc2b7..934a3e4ec 100644
--- a/api/internal/crawl/crawler/crawler.go
+++ b/api/internal/crawl/crawler/crawler.go
@@ -105,6 +105,7 @@ func doCrawl(ctx context.Context, docsPtr *CrawlSeed, crawlers []Crawler, conv C
 	SetCreatedErrCount := 0
 	convErrCount := 0
 	deleteDocCount := 0
+	crawledDocCount := 0
 
 	// During the execution of the for loop, more Documents may be added into (*docsPtr).
 	for len(*docsPtr) > 0 {
@@ -114,7 +115,11 @@ func doCrawl(ctx context.Context, docsPtr *CrawlSeed, crawlers []Crawler, conv C
 		// remove the last Document in (*docPtr)
 		*docsPtr = (*docsPtr)[:(len(*docsPtr) - 1)]
 
+		crawledDocCount++
+		logger.Printf("Crawling doc %d: %s %s", crawledDocCount, tail.RepositoryURL, tail.FilePath)
+
 		if _, ok := seen[tail.ID()]; ok {
+			logger.Printf("this doc has been seen before")
 			seenDocCount++
 			continue
 		}
@@ -132,7 +137,15 @@ func doCrawl(ctx context.Context, docsPtr *CrawlSeed, crawlers []Crawler, conv C
 			continue
 		}
 
-		logger.Println("Crawling ", tail.RepositoryURL, tail.FilePath)
+		// If the Document represents a kustomization root, FetchDcoument will change
+		// the `filePath` field of the Document by adding `kustomization.yaml` or
+		// `kustomization.yml` or `kustomization` into the the field.
+		// Therefore, it is necessary to add the ID of the Document into seen before
+		// calling FetchDocument. Otherwise, the binary may enter into an infinite loop
+		// if a kustomization file points to its kustmozation root in its `resources` or
+		// `bases` field.
+		seen[tail.ID()] = struct{}{}
+
 		if err := match.FetchDocument(ctx, tail); err != nil {
 			logger.Printf("FetchDocument failed on %s %s: %v",
 				tail.RepositoryURL, tail.FilePath, err)
@@ -274,8 +287,12 @@ func CrawlGithub(ctx context.Context, crawlers []Crawler, conv Converter,
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
+		docCount := 0
 		for cdoc := range ch {
+			docCount++
+			logger.Printf("Processing doc %d found on Github", docCount)
 			if _, ok := seen[cdoc.ID()]; ok {
+				logger.Printf("the doc has been seen before")
 				continue
 			}
 			match := findMatch(cdoc.GetDocument(), crawlers)
diff --git a/api/internal/crawl/index/elasticsearch.go b/api/internal/crawl/index/elasticsearch.go
index 3226b4970..7d7ce2b9e 100644
--- a/api/internal/crawl/index/elasticsearch.go
+++ b/api/internal/crawl/index/elasticsearch.go
@@ -87,7 +87,7 @@ func (idx *index) responseErrorOrNil(info string, res *esapi.Response,
 
 	defer res.Body.Close()
 	if res.IsError() {
-		return fmt.Errorf("%s: %s", messageStart, res.String())
+		return fmt.Errorf("%s: %s [%d]", messageStart, res.String(), res.StatusCode)
 	}
 
 	if reader != nil {