Glossary
Definitions for common Codex terms and concepts
116 terms
| Term | Applies to | Definition |
|---|---|---|
| Action | Desktop app, Web, Mobile, CLI, IDE extension, Cloud | An operation performed by a person, ChatGPT, or Codex, such as editing a file, running a command, or using a connected service. |
| Agent | Desktop app, CLI, IDE extension, Cloud | The Codex agent that reasons over context, uses tools, and completes a task. |
| AGENTS.md | Desktop app, CLI, IDE extension, Cloud | Repository or user guidance file that gives Codex persistent instructions. |
| Analytics dashboard | Enterprise | Admin hub for ChatGPT workspace adoption and Codex-focused reporting. |
| API key sign-in | Desktop app, CLI, IDE extension | Authentication using an OpenAI API key. |
| Approval policy | Desktop app, CLI, IDE extension | Rules for when Codex must ask before taking an action. |
| Approval request | Desktop app, CLI, IDE extension | Codex asking to allow a restricted action. |
| Apps (configuration) | Desktop app, CLI, IDE extension | Codex configuration and app-server fields that store connector settings under the `apps` name. |
| Appshot | Desktop app | Snapshot of the frontmost app window sent to a ChatGPT or Codex chat. |
| Auth cache | Desktop app, CLI, IDE extension | Locally stored login credentials reused by Codex. |
| Automatic approval review | Desktop app, CLI, IDE extension | Model-based review of eligible approval requests before they proceed. |
| Scheduled task | Desktop app, Web | A prompt ChatGPT runs at a future time or on a recurring schedule, with its own settings and run history. |
| Scheduled run | Desktop app, Web | One execution of a scheduled task, including its status and any resulting findings. |
| Computer Use in the browser | Desktop app | Capability that lets ChatGPT operate the built-in browser directly. |
| Chat | Desktop app, Web, Mobile, CLI, IDE extension, Cloud | A saved space for exchanging messages with ChatGPT or Codex, including shared context, results, and actions. Quick chat starts a ChatGPT chat from Codex. |
| ChatGPT sign-in | Desktop app, CLI, IDE extension, Cloud | Authentication using a ChatGPT account and workspace permissions. |
| Chronicle | Desktop app | Opt-in feature that builds memories from recent screen context. |
| Cloud | Desktop app, IDE extension, Web | Mode where Codex works remotely in an OpenAI-managed environment. |
| Cloud environment | Cloud | Configured container setup used for Codex cloud chats. |
| Cloud chat | Cloud | A Codex chat that runs remotely in a cloud environment. |
| Codex | Desktop app, CLI, IDE extension, Web, Cloud, SDK | OpenAI's coding agent for software development tasks. |
| ChatGPT desktop app | Desktop | Desktop app with ChatGPT and Codex, including Chat and Work, projects, file previews, scheduled tasks, and developer tools. |
| Codex app-server | Desktop app, IDE extension, SDK | Local JSON-RPC server for embedding Codex threads, turns, approvals, history, and streamed events in custom clients. |
| Codex CLI | Terminal | Terminal client for running Codex interactively or in scripts. |
| Codex cloud | Web, Desktop app, IDE extension | OpenAI-managed execution environment where Codex can work on repository tasks remotely. |
| codex exec | CLI | CLI command for running Codex non-interactively from scripts or CI. |
| Codex IDE extension | IDE | Editor integration for using Codex inside IDEs like VS Code, JetBrains IDEs, Cursor, and Windsurf. |
| Codex SDK | SDK | Programmatic interface for building Codex-powered workflows or integrations. |
| Codex-managed worktree | Desktop app | A temporary worktree Codex creates and manages for a chat. |
| Compaction | Desktop app, CLI, IDE extension, Cloud | Summarizing older context so long-running work can continue. |
| Compliance API | Enterprise | API for exporting supported ChatGPT workspace records and audit metadata. |
| Computer Use | Desktop app | Desktop capability that lets ChatGPT interact with other applications through the UI. |
| config.toml | Desktop app, CLI, IDE extension | Local Codex configuration files. |
| Connected host | Desktop app, Mobile | Computer or development environment that provides files, tools, and shell access for ChatGPT or Codex chats opened through Remote. |
| Connector | Desktop app (ChatGPT Work, Codex), Web (ChatGPT Work) | A component of a plugin that connects ChatGPT or Codex to data and actions in an external service. |
| Conversation | Desktop app, Web, Mobile, CLI, IDE extension, Cloud | The ongoing exchange of messages and shared context between a person and ChatGPT or Codex within a chat. |
| Container cache | Cloud | Saved cloud container state reused to speed up future cloud chats. |
| Context | Desktop app, CLI, IDE extension, Cloud, SDK | Information Codex can use while working, such as files, prior messages, tool output, and instructions. |
| Context window | Desktop app, CLI, IDE extension, Cloud, SDK | The maximum amount of information the model can consider at once. |
| Custom agent | Desktop app, CLI | User-defined agent role with its own instructions and settings. |
| Deny-read rule | Desktop app, CLI, IDE extension, Enterprise | Filesystem permission rule that prevents Codex from reading sensitive paths or glob matches. |
| Diff | Desktop app, Git, Review | Set of Git file changes shown for inspection, comments, staging, or reverting. |
| Domain allowlist | Cloud | Set of domains Codex cloud can reach when agent internet access is enabled. |
| Environment (local) | Desktop app, Worktree | Desktop app configuration that tells Codex how to set up worktrees for a project. |
| Environment variable | Cloud, CLI, IDE extension | Runtime configuration value available during task execution. |
| Ephemeral session | CLI | Non-interactive run that skips saving session state after it completes. |
| Fast mode | CLI, IDE extension | Speed setting that makes supported models respond faster at a higher credit cost. |
| Filesystem permission | Desktop app, CLI, IDE extension | Permission profile rule that grants or denies read and write access to paths. |
| Finding | Desktop app | A notable result or issue surfaced by a scheduled task. |
| Full access | Desktop app, CLI, IDE extension | Mode where Codex runs without normal sandbox restrictions. |
| Git worktree | Desktop app, Git | A second checkout of the same repository for parallel branch work. |
| Handoff | Desktop app | Moving a chat and its work between Local and Worktree. |
| Heartbeat | Desktop app | A recurring scheduled task that returns ChatGPT to the same chat. |
| Hook | Desktop app, CLI, IDE extension | A lifecycle handler that runs when a Codex event matches, such as tool use, permission requests, or when a turn stops. |
| Hook event | Desktop app, CLI, IDE extension | Lifecycle point where configured hook handlers can run. |
| Hunk | Desktop app, Git, Review | Contiguous section of a diff that can be staged, unstaged, or reverted independently. |
| Inline comment | Desktop app | Line-specific feedback attached to a diff. |
| Live web search | Desktop app, CLI, IDE extension | Real-time web lookup for current information. |
| Local | Desktop app, CLI, IDE extension | Mode where Codex works on the user's computer. |
| Local chat | Desktop app, CLI, IDE extension | A ChatGPT or Codex chat that runs on the user's machine. |
| Maintenance script | Cloud | Optional script run when a cached cloud container resumes. |
| Managed configuration | Enterprise | Organization-controlled Codex defaults and restrictions. |
| MCP | Desktop app, CLI, IDE extension | Model Context Protocol, a standard for connecting Codex to external tools and context. |
| MCP resource | Desktop app, CLI, IDE extension | Readable context exposed by an MCP server for Codex to inspect. |
| MCP server | Desktop app, CLI, IDE extension | External tool or context provider exposed through MCP. |
| MCP tool | Desktop app, CLI, IDE extension | Action exposed by an MCP server that Codex can call during a task. |
| MDM | Enterprise | Mobile device management tooling for distributing device profiles and managed Codex settings. |
| Memories | Desktop app, CLI, IDE extension | Locally stored context Codex can reuse across sessions. |
| Model | Desktop app, CLI, IDE extension, Cloud, SDK | The AI model Codex uses for reasoning and tool work. |
| Network access | Desktop app, CLI, IDE extension, Cloud | Permission for commands or environments to reach the internet. |
| Network policy | Desktop app, CLI, IDE extension | Domain-based allow and deny rules that constrain sandboxed outbound network traffic. |
| Non-interactive mode | CLI | CLI mode for running Codex from scripts or CI. |
| Output schema | CLI | JSON Schema passed to `codex exec` to constrain the final response. |
| Permanent worktree | Desktop app | A long-lived worktree kept as its own project. |
| Permission profile | Desktop app, CLI, IDE extension | Named least-privilege policy that combines filesystem and network rules for local command execution. |
| Plan | Desktop app, CLI, IDE extension, Cloud | Codex's proposed or tracked steps for completing a task. |
| Plugin | Desktop app (ChatGPT Work, Codex), Web (ChatGPT Work), CLI | An installable bundle of capabilities such as skills, connectors, and tools. |
| Plugin manifest | Plugin authoring | Plugin metadata file that identifies a plugin and points to bundled skills, connector mappings, MCP servers, hooks, and metadata. |
| Prefix rule | Desktop app, CLI, IDE extension, Enterprise | Command-rule pattern that allows, prompts for, or forbids matching command prefixes. |
| Profile | CLI, IDE extension | Named configuration preset for Codex. |
| Progressive disclosure | Desktop app, CLI, IDE extension | Loading skill details only when needed to preserve context. |
| Project | Desktop app | A group of related chats and shared sources, or a local folder used for file-based work. |
| Prompt | Desktop app, CLI, IDE extension, Cloud, SDK | A question, instruction, or goal sent to ChatGPT or Codex. |
| Pull request review | Desktop app, CLI, GitHub | Codex review of changes or feedback on a pull request. |
| RBAC | Enterprise | Role-based access control for workspace permissions. |
| Read-only mode | Desktop app, CLI, IDE extension | Mode where Codex can inspect but not modify without approval. |
| Reasoning effort | Desktop app, CLI, IDE extension, SDK | Setting that controls how much reasoning budget a model uses. |
| Remote connection | Desktop app, Mobile | Connection that lets you access ChatGPT or Codex chats on another device through a connected host. |
| requirements.toml | Enterprise | Admin-enforced requirements file for managed Codex setups. |
| Review pane | Desktop app | Desktop app view for inspecting diffs, comments, and Git changes. |
| Rules | Desktop app, CLI, IDE extension | Policies that allow, prompt for, or deny command prefixes or permission exceptions. |
| Sandbox | Desktop app, CLI, IDE extension | Enforced boundary limiting what Codex commands can access or modify. |
| Sandbox mode | Desktop app, CLI, IDE extension | Configuration that defines Codex's filesystem and network limits. |
| Sandbox preset | SDK | SDK shorthand for common sandbox policies such as read-only, workspace-write, or full access. |
| Schedule | Desktop app | The timing rule for a scheduled task. |
| Secret | Cloud | Encrypted value available to setup scripts but removed before the agent phase. |
| Setup script | Desktop app worktrees | Script run before the agent starts to install dependencies or prepare tools. |
| Skill | Desktop app, CLI, IDE extension | Reusable workflow package with instructions and optional scripts or references. |
| Skill invocation | Desktop app, CLI, IDE extension | Explicit or implicit activation of a skill. |
| Slash command | CLI | Command entered with a leading slash to control or inspect a Codex CLI session. |
| Standalone scheduled task | Desktop app, Web | Scheduled task whose runs each start a new chat and report findings in Triage. |
| STDIO MCP server | CLI, IDE extension | MCP server launched as a local process by a configured command and arguments. |
| Streamable HTTP MCP server | CLI, IDE extension | MCP server reached over HTTP, optionally with bearer token or OAuth authentication. |
| Subagent | Desktop app, CLI | Specialized child agent spawned to work on part of a task. |
| Subagent workflow | Desktop app, CLI | Workflow where Codex runs delegated agents in parallel and combines their results. |
| Standalone task | Desktop app, CLI, IDE extension, Cloud | A Codex task that isn't grouped within a project. |
| Task | Desktop app, Web, Mobile, CLI, IDE extension, Cloud | A defined outcome ChatGPT or Codex works toward, such as fixing a bug, creating a document, or researching a topic. |
| Thread | App-server, SDK | A technical object in Codex app-server APIs that contains turns and stored conversation history. |
| Scheduled task in a chat | Desktop app, Web | A scheduled task that uses an existing chat's context and returns each run's results to that chat. |
| Thread fork | App-server, SDK | New thread branched from the stored history of an existing thread. |
| Turn | Desktop app, CLI, IDE extension, Cloud, SDK | One exchange in a chat, usually a user prompt plus the agent's response and actions. |
| Universal image | Cloud | Default Codex cloud container image with common tools preinstalled. |
| Web search cache | Desktop app, CLI, IDE extension | Pre-indexed search results Codex can use without live browsing. |
| ChatGPT Work | Desktop app, Web | The agent in ChatGPT for research, analysis, and creating documents, presentations, spreadsheets, and other finished work. |
| Worktree | Desktop app | Mode where Codex isolates changes in a separate Git worktree. |
| Writable roots | Desktop app, CLI, IDE extension | Directories Codex is allowed to modify. |