df46ea48a2
# Terminal Detection Metadata for Per-Terminal Scroll Scaling
## Summary
Expand terminal detection into structured metadata (`TerminalInfo`) with
multiplexer awareness, plus a testable environment shim and
characterization tests.
## Context / Motivation
- TUI2 owns its viewport and scrolling model (see
`codex-rs/tui2/docs/tui_viewport_and_history.md`), so scroll behavior
must be consistent across terminals and independent of terminal
scrollback quirks.
- Prior investigations show mouse wheel scroll deltas vary noticeably by
terminal. To tune scroll scaling (line increments per wheel tick) we
need reliable terminal identification, including when running inside
tmux/zellij.
- tmux is especially tricky because it can mask the underlying terminal;
we now consult `tmux display-message` client termtype/name to attribute
sessions to the actual terminal rather than tmux itself.
- This remains backwards compatible with the existing OpenTelemetry
user-agent token because `user_agent()` is still derived from the same
environment signals (now via `TerminalInfo`).
## Changes
- Introduce `TerminalInfo`, `TerminalName`, and `Multiplexer` with
`TERM_PROGRAM`/`TERM`/multiplexer detection and user-agent formatting in
`codex-rs/core/src/terminal.rs`.
- Add an injectable `Environment` trait + `FakeEnvironment` for testing,
and comprehensive characterization tests covering known terminals, tmux
client termtype/name, and zellij.
- Document module usage and detection order; update `terminal_info()` to
be the primary interface for callers.
## Testing
- `cargo test -p codex-core terminal::tests`
- manually checked ghostty, iTerm2, Terminal.app, vscode, tmux, zellij,
Warp, alacritty, kitty.
```
2025-12-18T07:07:49.191421Z INFO Detected terminal info terminal=TerminalInfo { name: Iterm2, term_program: Some("iTerm.app"), version: Some("3.6.6"), term: None, multiplexer: None }
2025-12-18T07:07:57.991776Z INFO Detected terminal info terminal=TerminalInfo { name: AppleTerminal, term_program: Some("Apple_Terminal"), version: Some("455.1"), term: None, multiplexer: None }
2025-12-18T07:08:07.732095Z INFO Detected terminal info terminal=TerminalInfo { name: WarpTerminal, term_program: Some("WarpTerminal"), version: Some("v0.2025.12.10.08.12.stable_03"), term: None, multiplexer: None }
2025-12-18T07:08:24.860316Z INFO Detected terminal info terminal=TerminalInfo { name: Kitty, term_program: None, version: None, term: None, multiplexer: None }
2025-12-18T07:08:38.302761Z INFO Detected terminal info terminal=TerminalInfo { name: Alacritty, term_program: None, version: None, term: None, multiplexer: None }
2025-12-18T07:08:50.887748Z INFO Detected terminal info terminal=TerminalInfo { name: VsCode, term_program: Some("vscode"), version: Some("1.107.1"), term: None, multiplexer: None }
2025-12-18T07:10:01.309802Z INFO Detected terminal info terminal=TerminalInfo { name: WezTerm, term_program: Some("WezTerm"), version: Some("20240203-110809-5046fc22"), term: None, multiplexer: None }
2025-12-18T08:05:17.009271Z INFO Detected terminal info terminal=TerminalInfo { name: Ghostty, term_program: Some("ghostty"), version: Some("1.2.3"), term: None, multiplexer: None }
2025-12-18T08:05:23.819973Z INFO Detected terminal info terminal=TerminalInfo { name: Ghostty, term_program: Some("ghostty"), version: Some("1.2.3"), term: Some("xterm-ghostty"), multiplexer: Some(Tmux { version: Some("3.6a") }) }
2025-12-18T08:05:35.572853Z INFO Detected terminal info terminal=TerminalInfo { name: Ghostty, term_program: Some("ghostty"), version: Some("1.2.3"), term: None, multiplexer: Some(Zellij) }
```
## Notes / Follow-ups
- Next step is to wire `TerminalInfo` into TUI2’s scroll scaling
configuration and add a per-terminal tuning table.
- The log output in TUI2 helps validate real-world detection before
applying behavior changes.
npm i -g @openai/codex
or brew install --cask codex
Codex CLI is a coding agent from OpenAI that runs locally on your computer.
If you want Codex in your code editor (VS Code, Cursor, Windsurf), install in your IDE
If you are looking for the cloud-based agent from OpenAI, Codex Web, go to chatgpt.com/codex
Quickstart
Installing and running Codex CLI
Install globally with your preferred package manager. If you use npm:
npm install -g @openai/codex
Alternatively, if you use Homebrew:
brew install --cask codex
Then simply run codex to get started:
codex
If you're running into upgrade issues with Homebrew, see the FAQ entry on brew upgrade codex.
You can also go to the latest GitHub Release and download the appropriate binary for your platform.
Each GitHub Release contains many executables, but in practice, you likely want one of these:
- macOS
- Apple Silicon/arm64:
codex-aarch64-apple-darwin.tar.gz - x86_64 (older Mac hardware):
codex-x86_64-apple-darwin.tar.gz
- Apple Silicon/arm64:
- Linux
- x86_64:
codex-x86_64-unknown-linux-musl.tar.gz - arm64:
codex-aarch64-unknown-linux-musl.tar.gz
- x86_64:
Each archive contains a single entry with the platform baked into the name (e.g., codex-x86_64-unknown-linux-musl), so you likely want to rename it to codex after extracting it.
Using Codex with your ChatGPT plan
Run codex and select Sign in with ChatGPT. We recommend signing into your ChatGPT account to use Codex as part of your Plus, Pro, Team, Edu, or Enterprise plan. Learn more about what's included in your ChatGPT plan.
You can also use Codex with an API key, but this requires additional setup. If you previously used an API key for usage-based billing, see the migration steps. If you're having trouble with login, please comment on this issue.
Model Context Protocol (MCP)
Codex can access MCP servers. To configure them, refer to the config docs.
Configuration
Codex CLI supports a rich set of configuration options, with preferences stored in ~/.codex/config.toml. For full configuration options, see Configuration.
Execpolicy
See the Execpolicy quickstart to set up rules that govern what commands Codex can execute.
Docs & FAQ
- Getting started
- Configuration
- Sandbox & approvals
- Execpolicy quickstart
- Authentication
- Automating Codex
- Advanced
- Zero data retention (ZDR)
- Contributing
- Install & build
- FAQ
- Open source fund
License
This repository is licensed under the Apache-2.0 License.