Bugfix

internal/knowledge/store.go

@@ -41,7 +41,7 @@ func Load(ctx context.Context, dir, dataDir string, embedder Embedder, rag bool,
 	}
 	entries, err := os.ReadDir(dir)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("read knowledge directory %q: %w", dir, err)
 	}
 	for _, e := range entries {
 		if e.IsDir() || !strings.HasSuffix(strings.ToLower(e.Name()), ".json") {
@@ -70,14 +70,27 @@ func Load(ctx context.Context, dir, dataDir string, embedder Embedder, rag bool,
 		s.docs = append(s.docs, d)
 	}
 	if rag && len(s.docs) > 0 {
+		if s.embedder == nil {
+			return nil, fmt.Errorf("RAG is enabled but no embedding provider is configured")
+		}
 		if err := s.index(ctx); err != nil {
 			return s, err
 		}
 	}
 	return s, nil
 }
-func (s *Store) Count() int { s.mu.RLock(); defer s.mu.RUnlock(); return len(s.docs) }
+func (s *Store) Count() int {
+	if s == nil {
+		return 0
+	}
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.docs)
+}
 func (s *Store) ByID(id string) (model.KnowledgeDoc, bool) {
+	if s == nil {
+		return model.KnowledgeDoc{}, false
+	}
 	s.mu.RLock()
 	defer s.mu.RUnlock()
 	for _, d := range s.docs {
@@ -88,6 +101,9 @@ func (s *Store) ByID(id string) (model.KnowledgeDoc, bool) {
 	return model.KnowledgeDoc{}, false
 }
 func (s *Store) Search(ctx context.Context, text string, topK int) ([]model.KnowledgeHit, error) {
+	if s == nil {
+		return nil, fmt.Errorf("knowledge store is not initialized")
+	}
 	s.mu.RLock()
 	docs := append([]model.KnowledgeDoc(nil), s.docs...)
 	vecs := make(map[string][]float64, len(s.vectors))

internal/knowledge/store_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 )
 
@@ -50,3 +51,38 @@ func TestLoadRequiresSourceMetadata(t *testing.T) {
 		t.Fatal("expected missing source to fail")
 	}
 }
+
+func TestLoadMissingDirectoryReturnsHelpfulError(t *testing.T) {
+	missing := filepath.Join(t.TempDir(), "does-not-exist")
+	_, err := Load(context.Background(), missing, t.TempDir(), nil, false, []string{"internal-kb"})
+	if err == nil {
+		t.Fatal("expected missing knowledge directory to fail")
+	}
+	if got := err.Error(); !strings.Contains(got, "read knowledge directory") || !strings.Contains(got, missing) {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}
+
+func TestNilStoreHelpersDoNotPanic(t *testing.T) {
+	var s *Store
+	if got := s.Count(); got != 0 {
+		t.Fatalf("Count()=%d, want 0", got)
+	}
+	if _, ok := s.ByID("KB1"); ok {
+		t.Fatal("nil store unexpectedly returned a document")
+	}
+	if _, err := s.Search(context.Background(), "vpn", 1); err == nil {
+		t.Fatal("expected Search on nil store to return an error")
+	}
+}
+
+func TestRAGRequiresEmbedderWhenDocumentsExist(t *testing.T) {
+	dir := t.TempDir()
+	doc := `{"id":"I1","title":"VPN intern","text":"gateway vpn","answer":"x","source":"internal-kb","language":"de-DE","communication_style":"formal"}`
+	if err := os.WriteFile(filepath.Join(dir, "internal.json"), []byte(doc), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := Load(context.Background(), dir, t.TempDir(), nil, true, []string{"internal-kb"}); err == nil {
+		t.Fatal("expected RAG without embedder to fail")
+	}
+}