Worked on the TonicAI/textual repository to deliver a new API feature supporting customizable redaction workflows. Developed and integrated a custom_entities parameter into redact, redact_bulk, and download_redacted_file endpoints, enabling users to specify custom PII entity IDs and ensuring consistent behavior across the API. Focused on aligning endpoint logic and error handling to reduce integration risk and future maintenance overhead. Enhanced developer documentation by clarifying the use of custom_entities in TextualNer docstrings, improving overall API usability. Utilized Python for API development and data redaction, with an emphasis on privacy compliance, operational efficiency, and facilitating third-party integration.