Worked on the modelcontextprotocol/typescript-sdk repository to enhance the reliability of OAuth 2.0 authentication flows. Focused on stabilizing the token exchange process by ensuring the redirect_uri from the provider configuration was correctly included in the token exchange request body. This adjustment addressed failures in authorization-code exchanges and improved security checks within the OAuth flow. The work involved client-side development and API integration, utilizing TypeScript to implement and test the fix. By resolving a critical bug in the authentication process, the changes contributed to a more robust and secure integration experience for applications relying on OAuth-based authentication.