single string tool response should just be string

[benjibc]

No description provided.

[Copilot]

Pull Request Overview

This PR refactors how tool response content is formatted in the Agent class to optimize for OpenAI API semantics, where single text responses can be represented as plain strings rather than arrays.

• Extracts tool content formatting logic into a dedicated _format_tool_message_content method
• Returns plain strings for single text responses instead of always using arrays
• Maintains backwards compatibility by still returning arrays for multiple text items

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
eval_protocol/pytest/default_agent_rollout_processor.py	Refactors tool message content formatting by extracting logic into a new method and optimizing single text responses
tests/pytest/test_tool_response_single_string.py	Adds comprehensive test coverage for the new tool content formatting behavior

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[Copilot]

The return type annotation is missing the import for Union. Add 'from typing import Union' to the imports.

[benjibc]

lol