Documentation inconsistency for `config` + MCP startup silently fails
Resolved 💬 0 comments Opened Sep 30, 2025 by varunursekar Closed Nov 10, 2025
What version of Codex is running?
codex-cli 0.42.0
Which model were you using?
gpt-5
What platform is your computer?
Darwin 24.6.0 arm64 arm
What steps can reproduce the bug?
Run codex --help and you will see that the documentation says that config overrides should be in JSON format.
<img width="1212" height="359" alt="Image" src="https://github.com/user-attachments/assets/bbe60570-8202-4e89-8124-1f2108db5a82" />
If you look at this section of the README on Github on the other hand, it says you should use TOML format.
I tried using JSON to configure and instantiate an MCP server at run time. Start up of the server failed silently, which is perhaps the more worrying bug.
What is the expected behavior?
_No response_
What do you see instead?
_No response_
Additional information
_No response_