Advancing Tool Support - Part 3

* Introduced ToolCallingManager to manage the tool calling activities for resolving and executing tools. A default implementation is provided. It can be used to handle explicit tool execution on the client-side, superseding the previous FunctionCallingHelper class. It’s ready to be instrumented via Micrometer, and support exception handling when tool calls fail.
* Introduced ToolCallExceptionConverter to handle exceptions in tool calling, and provided a default implementation propagating the error message to the chat morel.
* Introduced ToolCallbackResolver to resolve ToolCallback instances. A default implementation is provided (DelegatingToolCallbackResolver), capable of delegating the resolution to a series of resolvers, including static resolution (StaticToolCallbackResolver) and dynamic resolution from the Spring context (SpringBeanToolCallbackResolver).
* Improved configuration in ToolCallingChatOptions to enable/disable the tool execution within a ChatModel (superseding the previous proxyToolCalls option).
* Added unit and integration tests to cover all the new use cases and existing functionality which was not covered by autotests (tool resolution from Spring context).
* Deprecated FunctionCallbackResolver, AbstractToolCallSupport, and FunctionCallingHelper.

Relates to gh-2049

Signed-off-by: Thomas Vitale <[email protected]>

Author: ThomasVitale

spring-ai-core/src/main/java/org/springframework/ai/chat/model/AbstractToolCallSupport.java

@@ -32,6 +32,7 @@
 import org.springframework.ai.model.function.FunctionCallback;
 import org.springframework.ai.model.function.FunctionCallbackResolver;
 import org.springframework.ai.model.function.FunctionCallingOptions;
+import org.springframework.ai.model.tool.ToolCallingManager;
 import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 
@@ -44,7 +45,9 @@
  * @author Thomas Vitale
  * @author Jihoon Kim
  * @since 1.0.0
+ * @deprecated Use {@link ToolCallingManager} instead.
  */
+@Deprecated
 public abstract class AbstractToolCallSupport {
 
 	protected static final boolean IS_RUNTIME_CALL = true;

spring-ai-core/src/main/java/org/springframework/ai/chat/model/ChatResponse.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2023-2024 the original author or authors.
+ * Copyright 2023-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@
  * @author Soby Chacko
  * @author John Blum
  * @author Alexandros Pappas
+ * @author Thomas Vitale
  */
 public class ChatResponse implements ModelResponse<Generation> {
 
@@ -100,6 +101,16 @@ public ChatResponseMetadata getMetadata() {
 		return this.chatResponseMetadata;
 	}
 
+	/**
+	 * Whether the model has requested the execution of a tool.
+	 */
+	public boolean hasToolCalls() {
+		if (CollectionUtils.isEmpty(generations)) {
+			return false;
+		}
+		return generations.stream().anyMatch(generation -> generation.getOutput().hasToolCalls());
+	}
+
 	@Override
 	public String toString() {
 		return "ChatResponse [metadata=" + this.chatResponseMetadata + ", generations=" + this.generations + "]";

spring-ai-core/src/main/java/org/springframework/ai/model/function/DefaultFunctionCallbackResolver.java

@@ -28,6 +28,8 @@
 
 import org.springframework.ai.chat.model.ToolContext;
 import org.springframework.ai.model.function.FunctionCallback.SchemaType;
+import org.springframework.ai.tool.resolution.SpringBeanToolCallbackResolver;
+import org.springframework.ai.tool.resolution.TypeResolverHelper;
 import org.springframework.beans.BeansException;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
@@ -55,7 +57,9 @@
  * @author Christian Tzolov
  * @author Christopher Smith
  * @author Sebastien Deleuze
+ * @deprecated Use {@link SpringBeanToolCallbackResolver} instead.
  */
+@Deprecated
 public class DefaultFunctionCallbackResolver implements ApplicationContextAware, FunctionCallbackResolver {
 
 	private GenericApplicationContext applicationContext;

spring-ai-core/src/main/java/org/springframework/ai/model/function/FunctionCallbackResolver.java

@@ -16,14 +16,17 @@
 
 package org.springframework.ai.model.function;
 
+import org.springframework.ai.tool.resolution.ToolCallbackResolver;
 import org.springframework.lang.NonNull;
 
 /**
  * Strategy interface for resolving {@link FunctionCallback} instances.
  *
  * @author Christian Tzolov
  * @since 1.0.0
+ * @deprecated Use {@link ToolCallbackResolver} instead.
  */
+@Deprecated
 public interface FunctionCallbackResolver {
 
 	/**

spring-ai-core/src/main/java/org/springframework/ai/model/function/FunctionCallingHelper.java

@@ -23,6 +23,7 @@
 import java.util.Set;
 import java.util.function.Function;
 
+import org.springframework.ai.model.tool.ToolCallingManager;
 import reactor.core.publisher.Flux;
 
 import org.springframework.ai.chat.messages.AssistantMessage;
@@ -40,7 +41,10 @@
  * Helper class that reuses the {@link AbstractToolCallSupport} to implement the function
  * call handling logic on the client side. Used when the withProxyToolCalls(true) option
  * is enabled.
+ *
+ * @deprecated Use {@link ToolCallingManager} instead.
  */
+@Deprecated
 public class FunctionCallingHelper extends AbstractToolCallSupport {
 
 	public FunctionCallingHelper() {

spring-ai-core/src/main/java/org/springframework/ai/model/tool/DefaultToolCallingChatOptions.java

@@ -21,8 +21,6 @@
 import org.springframework.ai.tool.ToolCallback;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
-import org.springframework.util.CollectionUtils;
-import org.springframework.util.StringUtils;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -46,7 +44,7 @@ public class DefaultToolCallingChatOptions implements ToolCallingChatOptions {
 	private Map<String, Object> toolContext = new HashMap<>();
 
 	@Nullable
-	private Boolean toolCallReturnDirect;
+	private Boolean toolExecutionEnabled;
 
 	@Nullable
 	private String model;
@@ -123,13 +121,13 @@ public void setToolContext(Map<String, Object> toolContext) {
 
 	@Override
 	@Nullable
-	public Boolean getToolCallReturnDirect() {
-		return this.toolCallReturnDirect;
+	public Boolean isToolExecutionEnabled() {
+		return this.toolExecutionEnabled;
 	}
 
 	@Override
-	public void setToolCallReturnDirect(@Nullable Boolean toolCallReturnDirect) {
-		this.toolCallReturnDirect = toolCallReturnDirect;
+	public void setToolExecutionEnabled(@Nullable Boolean toolExecutionEnabled) {
+		this.toolExecutionEnabled = toolExecutionEnabled;
 	}
 
 	@Override
@@ -139,7 +137,12 @@ public List<FunctionCallback> getFunctionCallbacks() {
 
 	@Override
 	public void setFunctionCallbacks(List<FunctionCallback> functionCallbacks) {
-		throw new UnsupportedOperationException("Not supported. Call setToolCallbacks instead.");
+		if (functionCallbacks.stream().allMatch(ToolCallback.class::isInstance)) {
+			setToolCallbacks(functionCallbacks.stream().map(ToolCallback.class::cast).toList());
+		}
+		else {
+			throw new IllegalArgumentException("functionCallbacks must be instances of ToolCallback");
+		}
 	}
 
 	@Override
@@ -155,12 +158,12 @@ public void setFunctions(Set<String> functions) {
 	@Override
 	@Nullable
 	public Boolean getProxyToolCalls() {
-		return getToolCallReturnDirect();
+		return !isToolExecutionEnabled();
 	}
 
 	@Override
 	public void setProxyToolCalls(@Nullable Boolean proxyToolCalls) {
-		setToolCallReturnDirect(proxyToolCalls != null && proxyToolCalls);
+		setToolExecutionEnabled(proxyToolCalls == null || !proxyToolCalls);
 	}
 
 	@Override
@@ -250,7 +253,7 @@ public <T extends ChatOptions> T copy() {
 		options.setToolCallbacks(getToolCallbacks());
 		options.setTools(getTools());
 		options.setToolContext(getToolContext());
-		options.setToolCallReturnDirect(getToolCallReturnDirect());
+		options.setToolExecutionEnabled(isToolExecutionEnabled());
 		options.setModel(getModel());
 		options.setFrequencyPenalty(getFrequencyPenalty());
 		options.setMaxTokens(getMaxTokens());
@@ -262,55 +265,6 @@ public <T extends ChatOptions> T copy() {
 		return (T) options;
 	}
 
-	/**
-	 * Merge the given {@link ChatOptions} into this instance.
-	 */
-	public ToolCallingChatOptions merge(ChatOptions options) {
-		ToolCallingChatOptions.Builder builder = ToolCallingChatOptions.builder();
-		builder.model(StringUtils.hasText(options.getModel()) ? options.getModel() : this.getModel());
-		builder.frequencyPenalty(
-				options.getFrequencyPenalty() != null ? options.getFrequencyPenalty() : this.getFrequencyPenalty());
-		builder.maxTokens(options.getMaxTokens() != null ? options.getMaxTokens() : this.getMaxTokens());
-		builder.presencePenalty(
-				options.getPresencePenalty() != null ? options.getPresencePenalty() : this.getPresencePenalty());
-		builder.stopSequences(options.getStopSequences() != null ? new ArrayList<>(options.getStopSequences())
-				: this.getStopSequences());
-		builder.temperature(options.getTemperature() != null ? options.getTemperature() : this.getTemperature());
-		builder.topK(options.getTopK() != null ? options.getTopK() : this.getTopK());
-		builder.topP(options.getTopP() != null ? options.getTopP() : this.getTopP());
-
-		if (options instanceof ToolCallingChatOptions toolOptions) {
-			List<ToolCallback> toolCallbacks = new ArrayList<>(this.toolCallbacks);
-			if (!CollectionUtils.isEmpty(toolOptions.getToolCallbacks())) {
-				toolCallbacks.addAll(toolOptions.getToolCallbacks());
-			}
-			builder.toolCallbacks(toolCallbacks);
-
-			Set<String> tools = new HashSet<>(this.tools);
-			if (!CollectionUtils.isEmpty(toolOptions.getTools())) {
-				tools.addAll(toolOptions.getTools());
-			}
-			builder.tools(tools);
-
-			Map<String, Object> toolContext = new HashMap<>(this.toolContext);
-			if (!CollectionUtils.isEmpty(toolOptions.getToolContext())) {
-				toolContext.putAll(toolOptions.getToolContext());
-			}
-			builder.toolContext(toolContext);
-
-			builder.toolCallReturnDirect(toolOptions.getToolCallReturnDirect() != null
-					? toolOptions.getToolCallReturnDirect() : this.getToolCallReturnDirect());
-		}
-		else {
-			builder.toolCallbacks(this.toolCallbacks);
-			builder.tools(this.tools);
-			builder.toolContext(this.toolContext);
-			builder.toolCallReturnDirect(this.toolCallReturnDirect);
-		}
-
-		return builder.build();
-	}
-
 	public static Builder builder() {
 		return new Builder();
 	}
@@ -363,16 +317,21 @@ public ToolCallingChatOptions.Builder toolContext(String key, Object value) {
 		}
 
 		@Override
-		public ToolCallingChatOptions.Builder toolCallReturnDirect(@Nullable Boolean toolCallReturnDirect) {
-			this.options.setToolCallReturnDirect(toolCallReturnDirect);
+		public ToolCallingChatOptions.Builder toolExecutionEnabled(@Nullable Boolean toolExecutionEnabled) {
+			this.options.setToolExecutionEnabled(toolExecutionEnabled);
 			return this;
 		}
 
 		@Override
 		@Deprecated // Use toolCallbacks() instead
 		public ToolCallingChatOptions.Builder functionCallbacks(List<FunctionCallback> functionCallbacks) {
 			Assert.notNull(functionCallbacks, "functionCallbacks cannot be null");
-			return toolCallbacks(functionCallbacks.stream().map(ToolCallback.class::cast).toList());
+			if (functionCallbacks.stream().allMatch(ToolCallback.class::isInstance)) {
+				return toolCallbacks(functionCallbacks.stream().map(ToolCallback.class::cast).toList());
+			}
+			else {
+				throw new IllegalArgumentException("functionCallbacks must be instances of ToolCallback");
+			}
 		}
 
 		@Override
@@ -395,9 +354,9 @@ public ToolCallingChatOptions.Builder function(String function) {
 		}
 
 		@Override
-		@Deprecated // Use toolCallReturnDirect() instead
+		@Deprecated // Use toolExecutionEnabled() instead
 		public ToolCallingChatOptions.Builder proxyToolCalls(@Nullable Boolean proxyToolCalls) {
-			return toolCallReturnDirect(proxyToolCalls != null && proxyToolCalls);
+			return toolExecutionEnabled(proxyToolCalls == null || !proxyToolCalls);
 		}
 
 		@Override