Configuration & Setup

Articles on Codex config.toml, hooks, environment setup and customisation.

307 articles

How Coding Agents Fail Their Users: What 20,574 Real-World Sessions Reveal About Misalignment — and How Codex CLI Defends Against the Seven Failure Forms

A large-scale observational study of 20,574 coding-agent sessions identifies seven recurring misalignment forms. We map each failure pattern to Codex CLI's constraint enforcement layer — hooks, approval policies, AGENTS.md, and sandbox isolation — showing how deterministic guardrails absorb what probabilistic instruction-following cannot.

Rule Taxonomy and Evolution in AI IDEs: What 7,310 Mined Rules Reveal About How Developers Configure Coding Agents — and How to Structure Codex CLI's AGENTS.md

Two empirical studies — 7,310 rules from 83 projects and 401 Cursor repositories — reveal a five-category taxonomy of coding agent rules, a persistent gap between what developers value and what they write, and a 22.99% compliance improvement from iterative evolution. Mapped to Codex CLI AGENTS.md structure, per-directory overrides, and PostToolUse enforcement hooks.

Beyond the Prompt: Codex CLI Mastery

Most developers treat Codex CLI as a chat box. The real value sits past the prompt, in AGENTS.md, skills, subagents, profiles, MCP servers and directory layout. This guide covers everything between installation and genuine mastery.

Codex CLI v0.120 Release Deep Dive

Codex CLI v0.120.0 landed on 11 April 2026, one day after the feature-heavy v0.119.0 release that brought Realtime V2 voice sessions and richer MCP App.

Advanced AGENTS.md Patterns for Monorepos

Monorepos concentrate a large surface area of code under a single Git root, and that concentration creates a fundamental tension for AI coding agents.

Migrating from Cursor to Codex CLI

Cursor's June 2025 pricing overhaul — replacing predictable 500-request plans with variable credit pools — sent a visible slice of its user base searching.