Worked on backend improvements for the jlowin/fastmcp and run-llama/llama_index repositories, focusing on reliability and developer experience. Developed a Python decorator to standardize API error handling in fastmcp, addressing rate limits and timeouts while enhancing documentation, type checking, and test coverage. In llama_index, implemented a mechanism to coerce filter values to match Weaviate collection schema types, reducing query errors and improving data integrity. Expanded testing and updated lockfiles to ensure reproducible builds across both projects. Leveraged skills in API development, data handling, and error handling to deliver features that streamline backend workflows and support robust API integrations.