Experiment: a Codex plugin for reusable project guidance maps in AGENTS.md

[Heyu2002]

I built a lightweight Codex plugin experiment around repository-local guidance maps:

https://github.com/Heyu2002/Code-Project-Guidance-Map

The plugin generates and refreshes a compact AGENTS.md action map for a codebase. It focuses on information that future Codex sessions often need before editing:

• module ownership
• task routing
• dependency boundaries
• project-specific editing rules
• key entry points for each module

The goal is not to create broad project documentation or replace reading source code. The goal is to give Codex a small, durable navigation layer so it can understand large modular repositories faster and make fewer wrong assumptions.

This experiment was inspired by a Codex feature request I opened here:

#26007

For now I’m treating this as an external/plugin-level workflow, not a request for an unsolicited core PR. I’m mainly interested in feedback from people using Codex on larger repositories:

• Do you run into repeated architecture rediscovery across sessions?
• Would a compact AGENTS.md module map help?
• What information would be most useful or dangerous to persist?
• Should this stay as a plugin-level convention, or is there value in a standardized built-in workflow later?

Feedback and use cases are welcome.

If this resonates with your workflow, comments on either the forum thread or the GitHub issue would help clarify whether this is a broader Codex need or just a niche workflow.