Codex Knowledge Base
The OpenAI Developer Docs MCP Server: Giving Codex CLI Live Access to Its Own Documentation
Documentation MCP servers have become essential infrastructure for coding agents. Context7 indexes thousands of third-party libraries; Repomix serves.
Codex CLI Official Workflow Recipes: Nine Patterns That Structure the Developer Loop
OpenAI's developer documentation now includes a dedicated Workflows page that codifies nine canonical patterns for using Codex CLI across the software.
Codex CLI Model Routing in May 2026: GPT-5.5, GPT-5.4, Codex-Spark, and When to Use Each
The model lineup available to Codex CLI developers has changed materially since March 2026. GPT-5.5 arrived in late April as the new frontier, GPT-5.4.
The Codex CLI Instruction Stack: How Six Configuration Surfaces Shape Agent Behaviour
Codex CLI does not read a single instruction file. It assembles a composite instruction set from six distinct surfaces, each with its own scope, precedence.
Codex CLI Granular Approval Policies and the Auto-Review Subagent: Autonomous Yet Secure Workflows
Every Codex CLI user eventually confronts the same tension: you want the agent to work autonomously, but you also want to sleep at night. The original.
Codex CLI /goal: Persisted Long-Horizon Workflows with Pause, Resume, and Token Budgets
Most Codex CLI interactions follow a prompt-diff-done cadence: you describe what you want, approve the plan, and move on.
Building Custom MCP Servers for Codex CLI: A Practical Guide in TypeScript and Python
Codex CLI ships with powerful built-in tools — shell execution, file editing via apply_patch, and web search — but production workflows inevitably demand.
Codex CLI's Built-in MCPs Just Became First-Class Runtime Servers — What It Means for Memory and Plugins
On 7 May 2026, Codex CLI merged PR #21356, authored by jif-oai, which fundamentally rearchitects how built-in MCP servers (like the memories server) run.
GPT-5.5 Instant and chat-latest: Dynamic Model Pointers for Codex CLI Developers
On 5 May 2026, OpenAI replaced GPT-5.3 Instant with GPT-5.5 Instant as the default ChatGPT model and simultaneously shipped a new API model alias.
Debugging Codex CLI Sessions with the OpenAI Traces Dashboard and OTLP Export
When a Codex CLI session produces unexpected results — a hallucinated file path, a tool call that silently fails, or a subagent that takes an inexplicable.