Worked on the anthropics/claude-agent-sdk-python repository to enhance security by addressing a DNS rebinding vulnerability in the MCP dependency. Focused on dependency management and security patching, the developer upgraded MCP to version 1.23.0 or higher, ensuring that new installations of the SDK would not include the vulnerable library. This targeted update aligned with security advisories and improved the SDK’s secure defaults, reducing risk for downstream users. The work involved careful release hygiene and attention to security best practices, utilizing TOML for dependency specification and Python for SDK maintenance, and demonstrated a methodical approach to open source security maintenance.