diff --git a/pkg/providers/openai/chat_stream_test.go b/pkg/providers/openai/chat_stream_test.go
index 31373579..e331cb1d 100644
--- a/pkg/providers/openai/chat_stream_test.go
+++ b/pkg/providers/openai/chat_stream_test.go
@@ -85,6 +85,10 @@ func TestOpenAIClient_ChatStreamRequest(t *testing.T) {
 			for {
 				chunk, err := stream.Recv()
 
+				if err == io.EOF {
+					return
+				}
+
 				require.NoError(t, err)
 				require.NotNil(t, chunk)
 			}
diff --git a/pkg/providers/testing/lang.go b/pkg/providers/testing/lang.go
index d14c439e..982bad8e 100644
--- a/pkg/providers/testing/lang.go
+++ b/pkg/providers/testing/lang.go
@@ -60,7 +60,7 @@ func (m *RespStreamMock) Open() error {
 }
 
 func (m *RespStreamMock) Recv() (*schemas.ChatStreamChunk, error) {
-	if m.idx < len(m.Chunks) {
+	if m.idx >= len(m.Chunks) {
 		return nil, io.EOF
 	}
 
@@ -124,7 +124,7 @@ func (c *ProviderMock) Chat(_ context.Context, _ *schemas.ChatRequest) (*schemas
 }
 
 func (c *ProviderMock) ChatStream(_ context.Context, _ *schemas.ChatRequest) (clients.ChatStream, error) {
-	if c.chatStreams == nil || c.idx < len(*c.chatStreams) {
+	if c.chatStreams == nil || c.idx >= len(*c.chatStreams) {
 		return nil, clients.ErrProviderUnavailable
 	}
 
diff --git a/pkg/routers/router_test.go b/pkg/routers/router_test.go
index e0b28c90..92e0ab3e 100644
--- a/pkg/routers/router_test.go
+++ b/pkg/routers/router_test.go
@@ -260,14 +260,28 @@ func TestLangRouter_ChatStream(t *testing.T) {
 	langModels := []*providers.LanguageModel{
 		providers.NewLangModel(
 			"first",
-			ptesting.NewProviderMock([]ptesting.RespMock{{Msg: "1"}, {Msg: "2"}}),
+			ptesting.NewStreamProviderMock([]ptesting.RespStreamMock{
+				ptesting.NewRespStreamMock([]ptesting.RespMock{
+					{Msg: "Bill"},
+					{Msg: "Gates"},
+					{Msg: "entered"},
+					{Msg: "the"},
+					{Msg: "bar"},
+				}),
+			}),
 			budget,
 			*latConfig,
 			1,
 		),
 		providers.NewLangModel(
 			"second",
-			ptesting.NewProviderMock([]ptesting.RespMock{{Msg: "1"}}),
+			ptesting.NewStreamProviderMock([]ptesting.RespStreamMock{
+				ptesting.NewRespStreamMock([]ptesting.RespMock{
+					{Msg: "Knock"},
+					{Msg: "Knock"},
+					{Msg: "joke"},
+				}),
+			}),
 			budget,
 			*latConfig,
 			1,
@@ -298,13 +312,19 @@ func TestLangRouter_ChatStream(t *testing.T) {
 
 	go router.ChatStream(ctx, req, respC)
 
-	select {
-	case chunkResult := <-respC:
-		require.Nil(t, chunkResult.Error())
-		require.NotNil(t, chunkResult.Chunk().ModelResponse.Message.Content)
-	case <-time.Tick(5 * time.Second):
-		t.Error("Timeout while waiting for stream chat chunk")
+	chunks := make([]string, 0, 5)
+
+	for range 5 {
+		select { //nolint:gosimple
+		case chunk := <-respC:
+			require.Nil(t, chunk.Error())
+			require.NotNil(t, chunk.Chunk().ModelResponse.Message.Content)
+
+			chunks = append(chunks, chunk.Chunk().ModelResponse.Message.Content)
+		}
 	}
+
+	require.Equal(t, []string{"Bill", "Gates", "entered", "the", "bar"}, chunks)
 }
 
 func TestLangRouter_ChatStream_AllModelsUnavailable(t *testing.T) {
@@ -355,18 +375,16 @@ func TestLangRouter_ChatStream_AllModelsUnavailable(t *testing.T) {
 	respC := make(chan *schemas.ChatStreamResult)
 	defer close(respC)
 
-	actualErrReasons := make([]string, 0, 3)
-
 	go router.ChatStream(context.Background(), schemas.NewChatFromStr("tell me a dad joke"), respC)
 
+	errs := make([]string, 0, 3)
+
 	for range 3 {
 		result := <-respC
 		require.Nil(t, result.Chunk())
 
-		actualErrReasons = append(actualErrReasons, result.Error().Reason)
+		errs = append(errs, result.Error().Reason)
 	}
 
-	// TODO: We should not send the error message if the model was unavailable at the very begging,
-	//  so we have not started any streaming yet using it
-	require.Equal(t, []string{"modelUnavailable", "modelUnavailable", "allModelsUnavailable"}, actualErrReasons)
+	require.Equal(t, []string{"modelUnavailable", "modelUnavailable", "allModelsUnavailable"}, errs)
 }