Worked on the aws/amazon-ssm-agent repository to enhance observability and reliability by improving serial port logging and error reporting. Developed a decoupled startup path for serial port logging, introduced a dedicated logging path for serial port interactions, and added environment-aware testing support to validate behavior across dry-run sandboxes and EC2 deployments. Addressed a logging sequence issue to ensure credential failures are consistently reported, streamlining error tracking and state visibility. Utilized Go for backend development, focusing on robust error handling, logging, and testing practices. These changes improved troubleshooting efficiency and credential retrieval reliability across multiple deployment environments within the agent.