Worked on enhancing agent reliability for the mastra-ai/mastra repository by focusing on robust error handling and testing strategies. Addressed a critical bug by implementing comprehensive TypeScript tests that validate the agent’s fallback behavior during authentication failures, ensuring seamless transition from primary to secondary models. This approach involved integrating API error scenarios and verifying end-to-end fallback flows, which reduced the risk of downtime caused by credential issues. Emphasized thorough test coverage and traceability, reinforcing the agent’s resilience against authentication disruptions. Utilized TypeScript and testing frameworks to strengthen guardrails around authentication, ultimately improving service continuity and reducing incident risk.