Invalid finish reason when max_tokens is the stop reason for Bedrock Converse Stream #4374
Description
Bug description
The finish reason is hard coded to tool_use when that are tool calls even if a stop reason of max_tokens is encountered.
Environment
Spring AI 1.0.1
Steps to reproduce
Set max output tokens to a low value with a prompt that should use a tool call.
Expected behavior
Finish reason should be max_tokens.
Minimal Complete Reproducible example
Index: models/spring-ai-bedrock-converse/src/test/java/org/springframework/ai/bedrock/converse/BedrockProxyChatModelIT.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/models/spring-ai-bedrock-converse/src/test/java/org/springframework/ai/bedrock/converse/BedrockProxyChatModelIT.java b/models/spring-ai-bedrock-converse/src/test/java/org/springframework/ai/bedrock/converse/BedrockProxyChatModelIT.java
--- a/models/spring-ai-bedrock-converse/src/test/java/org/springframework/ai/bedrock/converse/BedrockProxyChatModelIT.java (revision c2103b0e6c5030abf28c3a9b088d408bf9af8347)
+++ b/models/spring-ai-bedrock-converse/src/test/java/org/springframework/ai/bedrock/converse/BedrockProxyChatModelIT.java (date 1757625472524)
@@ -335,6 +335,35 @@
assertThat(content).contains("30", "10", "15");
}
+ @ParameterizedTest(name = "{displayName} - {0} ")
+ @ValueSource(ints = { 50, 200 })
+ void streamFunctionCallTestWithMaxTokens(int maxTokens) {
+
+ UserMessage userMessage = new UserMessage(
+ // "What's the weather like in San Francisco? Return the result in
+ // Celsius.");
+ "What's the weather like in San Francisco, Tokyo and Paris? Return the result in Celsius.");
+
+ List<Message> messages = new ArrayList<>(List.of(userMessage));
+
+ var promptOptions = BedrockChatOptions.builder()
+ .maxTokens(maxTokens)
+ .model("anthropic.claude-3-5-sonnet-20240620-v1:0")
+ .toolCallbacks(List.of(FunctionToolCallback.builder("getCurrentWeather", new MockWeatherService())
+ .description(
+ "Get the weather in location. Return temperature in 36°F or 36°C format. Use multi-turn if needed.")
+ .inputType(MockWeatherService.Request.class)
+ .build()))
+ .build();
+
+ Flux<ChatResponse> response = this.chatModel.stream(new Prompt(messages, promptOptions));
+ ChatResponse lastResponse = response.blockLast();
+ String finishReason = lastResponse.getResult().getMetadata().getFinishReason();
+
+ logger.info("Finish reason: {}", finishReason);
+ assertThat(finishReason).isEqualTo("max_tokens");
+ }
+
@Test
void validateCallResponseMetadata() {
String model = "anthropic.claude-3-5-sonnet-20240620-v1:0";