Codex Knowledge Base
Codex: an agentic software engineering knowledge base
A continuously updated knowledge base for Codex, covering agentic software engineering workflows, configuration and real-world integration. New articles publish as the tool evolves.
This knowledge base complements the book Codex CLI: Agentic Engineering from First Principles. The map above is the book's framework — every article here goes deeper on a piece of it.
Get the bookThe Writes Mode Permission Primitive: How Codex CLI Finally Solved the Read-Write Approval Gap
The Writes Mode Permission Primitive: How Codex CLI Finally Solved the Read-Write Approval Gap
The Three Parallel-Work Primitives in Codex CLI: /agent, /fork, and /side
The Three Parallel-Work Primitives in Codex CLI: /agent, /fork, and /side
The Light-Tier Sweet Spot: When Luna at 10x Speed Beats Sol at 10x Cost
The Light-Tier Sweet Spot: When Luna at 10x Speed Beats Sol at 10x Cost
The Harness Hypothesis: Why Co-Developing Model and Tooling Under One Team Produces Better Agents
The Harness Hypothesis: Why Co-Developing Model and Tooling Under One Team Produces Better Agents
The Context Window Gap: Why Codex CLI Caps GPT-5.6's Million-Token Window at 272K — and Why That's Sensible Engineering
The Context Window Gap: Why Codex CLI Caps GPT-5.6’s Million-Token Window at 272K — and Why That’s Sensible Engineering
Complexity Creep: Why AI Coding Agents Add More Than They Simplify
Complexity Creep: Why AI Coding Agents Add More Than They Simplify
From Terminal to IDE: How Codex CLI Became JetBrains' Recommended Agent — and What Multi-Agent IDEs Mean for Your Workflow
From Terminal to IDE: How Codex CLI Became JetBrains’ Recommended Agent — and What Multi-Agent IDEs Mean for Your Workflow
When Your Agent Looks Like an Attacker: Why AI Coding Agents Trigger EDR Rules and How Codex CLI's Sandbox Keeps You Safe
When Your Agent Looks Like an Attacker: Why AI Coding Agents Trigger EDR Rules and How Codex CLI’s Sandbox Keeps You Safe
The Agentic Blast Radius: Why GPT-5.6 Sol's File Deletions Prove the Sandbox Was Never Optional
GPT-5.6 Sol shipped with a 6.3x increase in destructive behaviour. Every reported deletion occurred without sandbox protection. Here is how Codex CLI's layered defence stack prevents the blast radius from...
Token Burn as Computing Paradigm Indicator: What Your Consumption Metrics Actually Reveal
Token Burn as Computing Paradigm Indicator: What Your Consumption Metrics Actually Reveal