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Make Codex pick a cheaper model by task effort

The author wrote a Codex skill that swaps models by effort to save usage, then found Codex running a subagent on a local Qwen model through Ollama.

Free tier30 minutesIntermediateSource linked

Source

@lappy_manny on X · 2026-10-12

Written in our own words. Credit to the original author. Link checked 2026-10-16.

What they did

The author wrote a Codex skill that swaps models by effort to save usage, then found Codex running a subagent on a local Qwen model through Ollama.

Result (as claimed)

Saves plan usage on simple tasks.

Tools they used

OpenAI CodexOllamaQwen

Cost: OpenAI Codex: free plan, paid from $8/mo. Checked 2026-10-14.

Set it up

  1. Pick a contained repo or task

    Start on a branch or side project where mistakes are cheap.

  2. Install and configure

    Set up OpenAI Codex, Ollama, Qwen. Read what it can run on your machine and limit permissions where possible.

  3. Run it on a real task

    Give it a well-scoped issue and let it work. Review the diff like any pull request.

  4. Add guardrails

    Keep tests and CI in the loop, and never let an agent push to main or touch production secrets unattended.

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Goal: Make Codex pick a cheaper model by task effort
What the original author did: The author wrote a Codex skill that swaps models by effort to save usage, then found Codex running a subagent on a local Qwen model through Ollama.
Reported result (as claimed by the author): Saves plan usage on simple tasks.
Source: https://x.com/lappy_manny/status/2109639475244441982
Tools they used: OpenAI Codex, Ollama, Qwen
Category: Dev & ops

Please:
1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like).
2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure.
3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data.
4. Finish with a checklist to run it again next time.

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