AGENTS.md is silently truncated and instructions near the end ignored

What version of Codex CLI is running?

0.108.0-alpha.3

What subscription do you have?

Pro

Which model were you using?

gpt-5.3-codex

What platform is your computer?

macOS

What terminal emulator and version are you using (if applicable)?

iTerm

What issue are you seeing?

Codex silently truncates AGENTS.md at 32 KB (roughly 600–800 lines). Any instructions past that limit are dropped and never sent to the model - with no warning anywhere in the TUI, /stats, exec, or VS Code extension.

What steps can reproduce the bug?

1. Create an AGENTS.md larger than 32 KB with important instructions near the end
2. Start a Codex session
3. Ask Codex to follow those instructions or ask it to recall instructions near the end of the document - it won't, because they were never loaded.

What is the expected behavior?

Expected behavior: Codex should warn the user at startup when AGENTS.md is being truncated so they can take action (reduce the file or adjust project_doc_max_bytes in config.toml).

Actual behavior: No warning at all. Users assume Codex is unreliable or that AGENTS.md doesn't work properly, when in reality their instructions are being silently clipped.

Additional information

Claude Code on the other hand clearly and prominently displays a warning when the CLAUDE.md file is too big. This encourages users to trim down their instructions or customize configured limits.