Codex / concept
Codex memory
Memory is used to retain stable preferences, but project facts should still be based on repository files, documentation, and command output.

What is Codex memory suitable for?
Memory is used to save stable preferences, frequently used commands, project habits, and past pitfalls. It should not replace repository documentation, nor should it hold keys or temporary state.
- Suitable for: verification commands, publishing habits, collaboration preferences, common mistakes.
- Not suitable for: API keys, cookies, customer data, disposable accounts.
- Project facts are first written into AGENTS.md, README or code comments.
How to use memory
Think of memories as personal or project operational experiences. When encountering new tasks, you must still refer to the current repository files and command output, especially deployment, dependencies, interfaces and permissions.
Complete usage points
Supplement the core concepts, operation sequences, permission boundaries and verification requirements that are easily compressed and missed in official documents, making it easier for English readers to learn completely by page.
Memories and Project Facts
Codex memory is good for storing stable preferences, but it cannot replace the current repository. Project facts will change, dependencies will be upgraded, and deployment commands will be adjusted, so Codex should still read the current file and run the real command before executing the task.
Content suitable for writing into memory includes: your preferred output format, commonly used verification commands, long-standing pitfalls in a certain repository, and things you want to always check before committing. Contents not suitable for writing into memory include: keys, cookies, customer data, temporary accounts, and one-time debugging conclusions.
Project-level facts should be placed in AGENTS.md or README; personal preferences can be placed in user-level configuration; information that changes with tasks should be left in the current session summary. This reduces repeated explanations and prevents outdated memories from contaminating new tasks.
Study Checklist
Put the content on this page into real tasks and use the five dimensions of entry, context, permissions, verification and team rules to check whether you have truly mastered it.
Study Checklist
After reading this page, do not just remember the concept name. You should be able to place "Codex memory" back into a real Codex engineering workflow: where the task starts, what context the system loads, which actions need approval, how the result is verified, and how to roll back when it fails.
If this is a concept page, be specific about how it affects the real task: does it change context, permissions, execution paths, validation methods, or changes the team collaboration process.
- Be able to describe in your own words the specific problem this page solves, rather than just reciting the title.
- Able to write a minimal example task with goals, scope, prohibitions, and acceptance criteria.
- Be able to determine which information should be put into the current prompt and which should be captured as project rules or configurations.
- Be able to explain which long-term rules should go into AGENTS.md, and which runtime behavior should be handled by config.toml, permission profile, skills and MCP.
- Ability to check diffs, command output, test results, screenshots or PR notes after a task is completed instead of just trusting the natural language summary.
If this page is used for team training, ask learners to complete a small task with Codex: read and explain first, submit a plan, make the smallest useful change, and close with real verification commands plus human diff review.
Codex practical notes
Fill in the most overlooked execution details of Codex usage around local environments, privilege escalation, remote entry, automation failures, and rollbacks.
Codex Practical Notes
This page belongs to the core concepts of Codex. When learning, connect concepts to real-world implementation: will it change context, permissions, task splitting, verification paths, or change the way teams collaborate.
When handling tasks related to "Codex memory", always confirm the current Git status and working directory first. Codex can make changes quickly, but it does not automatically know which uncommitted edits came from the user, which files are off limits, or which commands may affect production.
- Prioritize using low-risk branches or working trees for local tasks, and review them with git diff after completion.
- When it comes to installation dependencies, networking, databases, deployment, push, deletion, and reset, Codex must first be asked to explain the impact before approval.
- Results generated by remote or collaborative portals must also be confirmed back to PR, CI, build logs and test evidence.
- Automated tasks must define failure output and exit conditions in advance to avoid Codex repeatedly trying in the wrong direction.
Think of Codex as an engineering teammate who can execute commands, rather than an assistant who can only write text. The closer you get to a real system, the greater the need for clear boundaries, evidence, and rollbacks.