Tools MethodToolCallback throwing an IllegalArgumentException

[yuchaozhou]

Bug description
In the latest version of the Spring AI framework (m7), the validateToolContextSupport method has a bug introduced during refactoring. Specifically, the variable handling in the if condition is incorrect, causing an IllegalArgumentException to be thrown erroneously when ToolContext is non-null and its context is non-empty. This behavior worked correctly in version m6, but the refactoring in m7 introduced this issue.

Below is a code comparison:

m6 version:

private void validateToolContextSupport(@Nullable ToolContext toolContext) {
    var isToolContextRequired = toolContext != null && !CollectionUtils.isEmpty(toolContext.getContext());
    var isToolContextAcceptedByMethod = Stream.of(toolMethod.getParameterTypes())
        .anyMatch(type -> ClassUtils.isAssignable(type, ToolContext.class));
    if (isToolContextRequired && !isToolContextAcceptedByMethod) {
        throw new IllegalArgumentException("ToolContext is not supported by the method as an argument");
    }
}

m7 version:

	private void validateToolContextSupport(@Nullable ToolContext toolContext) {
		var isNonEmptyToolContextProvided = toolContext != null && !CollectionUtils.isEmpty(toolContext.getContext());
		var isToolContextAcceptedByMethod = Stream.of(toolMethod.getParameterTypes())
			.anyMatch(type -> ClassUtils.isAssignable(type, ToolContext.class));
		if (isToolContextAcceptedByMethod && !isNonEmptyToolContextProvided) {
			throw new IllegalArgumentException("ToolContext is required by the method as an argument");
		}
	}

Although the code appears identical, in m7, the evaluation of isToolContextAcceptedByMethod seems to misbehave, likely due to incorrect variable scoping or context handling during refactoring, causing the exception to be thrown unexpectedly.

Environment

• Spring AI version: spring-ai-M7
• Java version: [Java 17]

Steps to reproduce
Using the Tools tool will cause this issue

Expected behavior
In version m7, the validateToolContextSupport method should behave as it did in m6, throwing an IllegalArgumentException only when ToolContext is non-null, its context is non-empty, and the method’s parameters do not support the ToolContext type. Currently, m7 incorrectly throws the exception, leading to functional issues.

Minimal Complete Reproducible example
Using Tools