Add test coverage for functions

[kowyo]

Summary

Add comprehensive test coverage for agent functions that can be verified by the agent itself.

Motivation

Currently, there's no automated way to verify that agent functions work correctly. Adding test coverage inspired by OpenAI's Harness Engineering approach will improve reliability and enable self-verification.

Proposed Solution

• Implement test coverage using pytest
• Design tests that the agent can run to verify its own functionality
• Focus on critical agent functions and edge cases

Acceptance Criteria

• Test framework (pytest) set up and configured
• Core agent functions have test coverage
• Tests can be run by the agent for self-verification
• Documentation on how to run tests

Additional Context

Inspired by https://openai.com/index/harness-engineering/