From 26c5674acba9ff5a0ef58b6e8aee8fca4c0a99b6 Mon Sep 17 00:00:00 2001
From: Peter Dolukhanov <peter@decoded.consulting>
Date: Thu, 5 Sep 2024 12:27:02 -0700
Subject: [PATCH] Fix where previous Assistant Messages were not being added to
 the parts list.

Results in: io.grpc.StatusRuntimeException: INVALID_ARGUMENT: Unable to submit request because it must include at least one parts field, which describes the prompt input. Learn more: https://cloud.google.com/vertex-ai/generative-ai/docs/model-reference/gemini
---
 .../ai/vertexai/gemini/VertexAiGeminiChatModel.java             | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/models/spring-ai-vertex-ai-gemini/src/main/java/org/springframework/ai/vertexai/gemini/VertexAiGeminiChatModel.java b/models/spring-ai-vertex-ai-gemini/src/main/java/org/springframework/ai/vertexai/gemini/VertexAiGeminiChatModel.java
index 497a839140..faca97ae27 100644
--- a/models/spring-ai-vertex-ai-gemini/src/main/java/org/springframework/ai/vertexai/gemini/VertexAiGeminiChatModel.java
+++ b/models/spring-ai-vertex-ai-gemini/src/main/java/org/springframework/ai/vertexai/gemini/VertexAiGeminiChatModel.java
@@ -431,7 +431,7 @@ else if (message instanceof UserMessage userMessage) {
 		else if (message instanceof AssistantMessage assistantMessage) {
 			List<Part> parts = new ArrayList<>();
 			if (StringUtils.hasText(assistantMessage.getContent())) {
-				List.of(Part.newBuilder().setText(assistantMessage.getContent()).build());
+				parts.add(Part.newBuilder().setText(assistantMessage.getContent()).build());
 			}
 			if (!CollectionUtils.isEmpty(assistantMessage.getToolCalls())) {
 				parts.addAll(assistantMessage.getToolCalls()