Codex Knowledge Base
Context Fragment Injection: Modular DeveloperInstructions via Plugins
Until today, Codex CLI assembled its system prompt as a single monolithic DeveloperInstructions blob — one giant string stuffed into the developer-role.
Codex CLI for Ruby on Rails Teams: AGENTS.md, Bundler Sandboxing, and RSpec Workflows
Ruby on Rails remains one of the most productive full-stack frameworks in production, powering applications from Shopify to GitHub.
Codex CLI Remote Connections: Running Agents on Remote Hosts with SSH, WebSocket, and Secure Tunnels
Your code lives on a beefy cloud devbox. Your credentials sit in a vault accessible only from a private subnet. Your CI runners spin up ephemeral containers.
Prompt Caching in Codex CLI: How the Agent Loop Stays Linear and How to Maximise Cache Hits
Every Codex CLI session resends the full conversation history on each turn. Without mitigation, this is quadratic in cost and latency. The engineering.
Codex CLI Plugin System: Building, Sharing, and Managing Reusable Agent Workflows
Codex CLI v0.122 elevated plugins from an app-only curiosity to a first-class workflow primitive across the entire Codex surface.
Codex CLI and Docker MCP Toolkit: Secure Containerised Tool Servers at Scale
The Model Context Protocol gives Codex CLI access to external tools — databases, filesystems, APIs, browsers.
Codex CLI Conversation Branching: /side, /fork, and Plan Mode Workflows
Codex CLI v0.122.0, released on 20 April 2026, introduced the /side slash command — an ephemeral fork that lets you ask a quick question mid-task without.
Amazon Bedrock Provider for Codex CLI: Multi-Cloud Model Access
Running Codex CLI against Amazon Bedrock has been one of the most requested features since the tool launched. Issue #10400, filed in February 2026.
Routing Codex CLI Through AI Gateways: Multi-Provider Access, Cost Control, and Failover
Codex CLI ships with first-class support for OpenAI models, but production teams rarely want a single point of failure, a single billing dimension.
Codex App Server Architecture: Building Custom Client Integrations with JSON-RPC
The Codex App Server is the protocol layer that decouples OpenAI's coding agent logic from its client surfaces.