feat: Enhance Anthropic integration with Thinking

- The `thinking` option is added to `AnthropicChatOptions` and `ChatCompletionRequest`.
- The `AnthropicApi` and `AnthropicChatModel` now handle `THINKING` and `REDACTED_THINKING` content blocks in responses.  New tests verify parsing of these blocks.
- Updated method signatures on ChatCompletionRequestBuilder, deprecating old builders with `with*` prefix in favor of those without.

Signed-off-by: Alexandros Pappas <[email protected]>

Author: apappascs

models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatModel.java

@@ -18,6 +18,7 @@
 
 import java.util.ArrayList;
 import java.util.Base64;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -36,6 +37,7 @@
 import org.springframework.ai.tool.definition.ToolDefinition;
 import org.springframework.ai.util.json.JsonParser;
 import org.springframework.lang.Nullable;
+
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
@@ -379,46 +381,49 @@ private ChatResponse toChatResponse(ChatCompletionResponse chatCompletion, Usage
 			return new ChatResponse(List.of());
 		}
 
-		List<Generation> generations = chatCompletion.content()
-			.stream()
-			.filter(content -> content.type() != ContentBlock.Type.TOOL_USE)
-			.map(content -> new Generation(new AssistantMessage(content.text(), Map.of()),
-					ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build()))
-			.toList();
-
-		List<Generation> allGenerations = new ArrayList<>(generations);
+		List<Generation> generations = new ArrayList<>();
+		List<AssistantMessage.ToolCall> toolCalls = new ArrayList<>();
+		for (ContentBlock content : chatCompletion.content()) {
+			switch (content.type()) {
+				case TEXT, TEXT_DELTA:
+					generations.add(new Generation(new AssistantMessage(content.text(), Map.of()),
+							ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build()));
+					break;
+				case THINKING, THINKING_DELTA:
+					Map<String, Object> thinkingProperties = new HashMap<>();
+					thinkingProperties.put("signature", content.signature());
+					generations.add(new Generation(new AssistantMessage(content.thinking(), thinkingProperties),
+							ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build()));
+					break;
+				case REDACTED_THINKING:
+					Map<String, Object> redactedProperties = new HashMap<>();
+					redactedProperties.put("data", content.data());
+					generations.add(new Generation(new AssistantMessage(null, redactedProperties),
+							ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build()));
+					break;
+				case TOOL_USE:
+					var functionCallId = content.id();
+					var functionName = content.name();
+					var functionArguments = JsonParser.toJson(content.input());
+					toolCalls.add(
+							new AssistantMessage.ToolCall(functionCallId, "function", functionName, functionArguments));
+					break;
+			}
+		}
 
 		if (chatCompletion.stopReason() != null && generations.isEmpty()) {
 			Generation generation = new Generation(new AssistantMessage(null, Map.of()),
 					ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build());
-			allGenerations.add(generation);
+			generations.add(generation);
 		}
 
-		List<ContentBlock> toolToUseList = chatCompletion.content()
-			.stream()
-			.filter(c -> c.type() == ContentBlock.Type.TOOL_USE)
-			.toList();
-
-		if (!CollectionUtils.isEmpty(toolToUseList)) {
-			List<AssistantMessage.ToolCall> toolCalls = new ArrayList<>();
-
-			for (ContentBlock toolToUse : toolToUseList) {
-
-				var functionCallId = toolToUse.id();
-				var functionName = toolToUse.name();
-				var functionArguments = JsonParser.toJson(toolToUse.input());
-
-				toolCalls
-					.add(new AssistantMessage.ToolCall(functionCallId, "function", functionName, functionArguments));
-			}
-
+		if (!CollectionUtils.isEmpty(toolCalls)) {
 			AssistantMessage assistantMessage = new AssistantMessage("", Map.of(), toolCalls);
 			Generation toolCallGeneration = new Generation(assistantMessage,
 					ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build());
-			allGenerations.add(toolCallGeneration);
+			generations.add(toolCallGeneration);
 		}
-
-		return new ChatResponse(allGenerations, this.from(chatCompletion, usage));
+		return new ChatResponse(generations, this.from(chatCompletion, usage));
 	}
 
 	private ChatResponseMetadata from(AnthropicApi.ChatCompletionResponse result) {
@@ -575,7 +580,7 @@ else if (message.getMessageType() == MessageType.TOOL) {
 		List<ToolDefinition> toolDefinitions = this.toolCallingManager.resolveToolDefinitions(requestOptions);
 		if (!CollectionUtils.isEmpty(toolDefinitions)) {
 			request = ModelOptionsUtils.merge(request, this.defaultOptions, ChatCompletionRequest.class);
-			request = ChatCompletionRequest.from(request).withTools(getFunctionTools(toolDefinitions)).build();
+			request = ChatCompletionRequest.from(request).tools(getFunctionTools(toolDefinitions)).build();
 		}
 
 		return request;

models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatOptions.java

@@ -56,6 +56,7 @@ public class AnthropicChatOptions implements ToolCallingChatOptions {
 	private @JsonProperty("temperature") Double temperature;
 	private @JsonProperty("top_p") Double topP;
 	private @JsonProperty("top_k") Integer topK;
+	private @JsonProperty("thinking") ChatCompletionRequest.ThinkingConfig thinking;
 
 	/**
 	 * Collection of {@link ToolCallback}s to be used for tool calling in the chat
@@ -94,6 +95,7 @@ public static AnthropicChatOptions fromOptions(AnthropicChatOptions fromOptions)
 			.temperature(fromOptions.getTemperature())
 			.topP(fromOptions.getTopP())
 			.topK(fromOptions.getTopK())
+			.thinking(fromOptions.getThinking())
 			.toolCallbacks(fromOptions.getToolCallbacks())
 			.toolNames(fromOptions.getToolNames())
 			.internalToolExecutionEnabled(fromOptions.isInternalToolExecutionEnabled())
@@ -163,6 +165,14 @@ public void setTopK(Integer topK) {
 		this.topK = topK;
 	}
 
+	public ChatCompletionRequest.ThinkingConfig getThinking() {
+		return this.thinking;
+	}
+
+	public void setThinking(ChatCompletionRequest.ThinkingConfig thinking) {
+		this.thinking = thinking;
+	}
+
 	@Override
 	@JsonIgnore
 	public List<FunctionCallback> getToolCallbacks() {
@@ -319,6 +329,16 @@ public Builder topK(Integer topK) {
 			return this;
 		}
 
+		public Builder thinking(ChatCompletionRequest.ThinkingConfig thinking) {
+			this.options.thinking = thinking;
+			return this;
+		}
+
+		public Builder thinking(AnthropicApi.ThinkingType type, Integer budgetTokens) {
+			this.options.thinking = new ChatCompletionRequest.ThinkingConfig(type, budgetTokens);
+			return this;
+		}
+
 		public Builder toolCallbacks(List<FunctionCallback> toolCallbacks) {
 			this.options.setToolCallbacks(toolCallbacks);
 			return this;