TurboDraft is an external editor optimized for Ctrl-G loops in Claude Code and Codex CLI:

- very fast startup (on my machine: ~50ms to usable, <10ms to first render) - minimal editing surface focused on immediate typing - built specifically for prompt-edit iteration speed

Related tool: https://github.com/gradigit/claude-pager It keeps session context visible while editing and adds OSC-8 clickable links for file/web refs in supported terminals. (<5ms to first render)

It also has an "Improve Prompt" prompt engineering feature, but that's more for my own personal workflow.

I found it extremely useful to hook codex spark up to it, and have my draft prompts get engineered and optimized in <5s. Ever since spark release, pretty much all of my prompts follow a strict structure and it has greatly improved output quality for me.