Codex CLI Ignores Available MCP Servers Until Manually Prompted

I think Codex CLI has an issue with MCP loading and discovery. I’ve run multiple sessions, and unless I nudge the model to use a specific MCP server or tool, it doesn’t seem to recognize they exist. I have to keep prompting it until it uses them, at which point they become available in context. However, if it encounters a problem that another MCP server could help in solving, it still doesn’t recognize that it has the right tool for the job. I’m not sure if this is an issue with Codex itself or the GPT model, but it tends to stick to raw terminal commands rather than using the MCP tools I provide. I’ve tried GPT models in other harnesses, and while they were generally weaker at discovering and using tools than other providers, something like OpenCode was much better at finding and using MCP servers compared to Codex. I’d like to point this out in case others have seen the same issue and to figure out steps to reproduce it so it can be fixed. Also, every time you type /new, it reloads the MCP servers and makes you wait, which feels unnecessary. Other harnesses load them once in the background without forcing me to wait for MCP server initialization.

codex-cli 0.141.0
Windows:
Edition Windows 11 Pro
Version 25H2
OS build 26200.8655
Experience Windows Feature Experience Pack 1000.26100.315.0

GPT model used: GPT 5.5- high

Terminal: Windows Terminal
Shell: Powershell