Fix dashscope structured output

[Mozhimomo]

AgentScope-Java Version

2.0.0-SNAPSHOT

Description

This PR fixes DashScope structured output for calls such as ReActAgent.call(msgs, MyClass.class, ctx).

Previously, DashScopeChatModel advertised native structured-output support, so ReActAgent selected the native response_format path. However, the DashScope formatter did not map GenerateOptions.responseFormat into DashScopeParameters.responseFormat, so the actual DashScope request body did not include response_format. As a result, DashScope could return natural-language text instead of JSON, wrapNativeStructuredResult(...) failed to parse it, and Msg.hasStructuredData() remained false.

Changes made:

• Set DashScopeChatModel.supportsNativeStructuredOutput() to false, so DashScope structured-output calls use the fallback generate_response tool path.
• Added GenerateOptions.responseFormat mapping in DashScopeToolsHelper.applyOptions(...), so explicit DashScope response_format options are no longer dropped.
• Added regression tests for response format mapping and DashScope structured-output routing.
• Added a developer note documenting the root cause, fix, and verification steps.

How to test:

• mvn -pl agentscope-core "-Dtest=DashScopeToolsHelperComprehensiveTest,DashScopeChatModelTest" test
• mvn -pl agentscope-core spotless:check

Checklist

Please check the following items before code is ready to be reviewed.

• Code has been formatted with mvn spotless:apply
• All tests are passing (mvn test)
• Javadoc comments are complete and follow project conventions
• Related documentation has been updated (e.g. links, examples, etc.)
• Code is ready for review

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[itxaiohanglover]

Good fix! Setting supportsNativeStructuredOutput to false for DashScope and forwarding ResponseFormat through the tools helper ensures structured output works correctly. The test coverage for the response format forwarding is solid.