Comment by nextaccountic

9 hours ago

Codex CLI is quite happy running RTK. Well with GPT 5.5 xhigh anyway

One thing that irks me is that when it doesn't support eg. a cli flag of find, it gives an error message rather than sending the full output of the command instead. Then the agent wastes tokens retrying, or worse, doesn't even try because the prompting may make them afraid to not run commands without rtk

how effective is RTK for you? worth using?

  • I found judicial use of rtk on specific commands that you know can be improved with rtk, e.g. go test, pnpm test (vitest), etc. to be worthwhile, at least in CC. But using their default setup which is to prepend rtk to everything is more trouble than its worth. I have a custom-built hook that prepends rtk based on a hierarchical whitelist.

    And you should disable the savings reporting feature since it’s worse than useless—it breaks sandboxing and always reports ~100% savings for me because rtk obviously doesn’t know about the head/tail the agent pipes into.

  • I can't find the relevant issues in their repo, but I've been somewhat skeptical of their tool over-reporting token savings and there are many issues to that effect in the repo.

    I'm not likely to install it again in my latest configuration, instead applying some specific tricks to things like `make test` to spit out zero output exit on unsuccessful error codes, that sort of thing. Anecdotally, I see GPT-5.5 often automatically applying context limiting flags to the bash it writes :shrug:

    • I've had the same experience with RTK, where my agent got stuck in a loop with a faulty RTK command and could not escape it since RTK hard overwrites anything automatically. I've uninstalled it again for the time being.