Developed the Apex Performance Antipattern Detection and Auto-Fix Toolkit for the salesforcecli/mcp repository, introducing an AST-based analysis pipeline to identify and automatically correct common Apex performance issues such as SOQL queries lacking WHERE or LIMIT clauses and unused fields. Leveraged JavaScript and TypeScript to implement static analysis detectors, comprehensive fix instructions with severity levels, and robust unit testing that achieved over 95% coverage. Integrated the toolkit into the MCP workflow, streamlined AST handling under a unified parser, and improved code maintainability by removing redundancies. Enhanced collaboration and stability by addressing test reliability and updating documentation for developer onboarding.