OpenAI Codex: what it remembers, who owns it, and what it costs
thecontinuitylayer.com/coding-agents/openai-codexOpenAI's coding agent, run locally through the CLI, an IDE or the desktop app, and in the cloud through ChatGPT.
- 1Yes
Does OpenAI Codex remember across sessions?
Yes, by OpenAI's own page.
AGENTS.md files (global, repository and subfolder) load automatically; local memories carry context from earlier chats into later work until reset.
Yes means: Persistent instructions or stored memory carry into a new session without you pasting them again.
- 2Yes
Can you see what OpenAI Codex remembered?
Yes, by OpenAI's own page.
Local memories are files under ~/.codex/memories/ you can open; AGENTS.md is a plain file.
Yes means: A file or panel lists the stored memory.
- 3Partly
Can you edit OpenAI Codex's memory?
Partly, by OpenAI's own page.
AGENTS.md is yours to edit; the memory files are generated state, and the docs say not to rely on editing them by hand.
Yes means: The memory is editable by you.
- 4Yes
Can you delete or turn off OpenAI Codex's memory?
Yes, by OpenAI's own page.
Local memories are off by default; the app's Personalization settings have a control to delete Codex memories, and there is a per-chat /memories toggle.
Yes means: A documented way to delete it or switch it off.
- 5Yes
Does OpenAI Codex keep memory in a file you own?
Yes, by OpenAI's own page.
AGENTS.md and ~/.codex/config.toml are plain files; memories are stored as local files under ~/.codex/memories/.
Yes means: The memory lives in a plain file on your machine or in your repository.
- 6Yes
Does OpenAI Codex read a format other tools read?
Yes, by OpenAI's own page.
Uses AGENTS.md, described as an open-format README for agents; the docs do not mention reading CLAUDE.md or .cursorrules.
Yes means: It reads a shared convention such as AGENTS.md, so the same file works elsewhere.
- 7Partly
Does OpenAI Codex use your code for training by default?
Partly, by OpenAI's own page.
The pricing page lists "no training on your data by default" for Business, Enterprise and API key use, and not for Plus or Pro; the consumer opt-out article could not be read on the day checked.
Yes means: Here no is the good answer: the maker's page says your data is not used for training. Yes means it is unless you opt out; partly means it depends on the plan or the page does not give the default.
- 8Yes
What does OpenAI Codex cost?
Yes, by OpenAI's own page.
Free and Go ($8) include Codex in the desktop app only; Plus at $20 a month is the entry tier with the CLI, IDE, web and cloud; Pro from $100; Business $20 to $25 a user.
Yes means: A free tier exists and the entry paid price is published.
What these grades say about continuity, and what they do not.
Every grade on this site is read from the maker's own pages. The Continuity Framework asks five things of any system that carries state: that it carry, govern, evolve, prove and forget. These tests reach carry, govern, prove and forget; they do not reach evolve, which no maker's page documents in a gradeable way. A high letter is a good coding agent, not a continuity layer.
- C1 RemembersCarry
- Remembering across sessions is question C1: state outlives the session that created it.
- C2 See itProve
- Being able to see the stored memory is the smallest form of question P1: the owner can inspect what is carried.
- C3 Edit itGovern
- An editable memory means the owner, not only the agent, has write authority (question G1, in part).
- C4 Delete itForget
- Deleting or switching off memory is rung 5 of the erasure ladder for the store the agent keeps; summaries and indexes it built are not covered unless documented. Rung 5 of the erasure ladder: delete the record.
- C5 Your fileCarry
- Memory in a file you own is portability by construction: question C3 answered without an export.
- C6 PortableCarry
- Reading a shared convention such as AGENTS.md is question C2: the same file works when the agent changes.
- C7 TrainingGovern
- Not training on your code by default is a scope boundary on the maker's side: what leaves the record and where it may go.
License as stated: Apache-2.0 for the Codex CLI repository; the cloud service is proprietary.. Every grade above is read from OpenAI's own page on the day shown. If a page has changed, tell us.