Kristina focused on enhancing the reliability and security of the OpenID4VP authentication flow in the openid/OpenID4VP repository. She addressed a bug where the client_id in incoming requests did not consistently match the aud claim in responses, which could have led to client misidentification. By aligning these parameters, Kristina reduced the risk of authentication errors and improved the overall robustness of the Verified Presentation flow. Her work involved targeted changes using OAuth 2.0 and OpenID Connect protocols, delivered as a concise, auditable update. The fix was implemented in text-based configuration, allowing for straightforward testing and rollback if necessary.