Developed an opt-in feature for the openai/codex repository to enhance terminal visualization guidance within the Codex TUI. The work focused on gating new instructions behind a feature flag, allowing targeted testing by TUI dogfooders without impacting existing workflows. By appending additional guidance to developer instructions for specific TUI flows, the approach enabled controlled rollout and reduced risk of disruption. The implementation leveraged Rust for TUI development and incorporated configuration management and feature gating techniques. This groundwork supports future expansion of terminal-based visualization features while maintaining stability and flexibility for users who choose to enable the new functionality during testing.