Felipe Coury
0393a485ed
## Problem The TUI had shell-style Up/Down history recall, but `Ctrl+R` did not provide the reverse incremental search workflow users expect from shells. Users needed a way to search older prompts without immediately replacing the current draft, and the interaction needed to handle async persistent history, repeated navigation keys, duplicate prompt text, footer hints, and preview highlighting without making the main composer file even harder to review. https://github.com/user-attachments/assets/5165affd-4c9a-46e9-adbd-89088f5f7b6b <img width="1227" height="722" alt="image" src="https://github.com/user-attachments/assets/8bc83289-eeca-47c7-b0c3-8975101901af" /> ## Mental model `Ctrl+R` opens a temporary search session owned by the composer. The footer line becomes the search input, the composer body previews the current match only after the query has text, and `Enter` accepts that preview as an editable draft while `Esc` restores the draft that existed before search started. The history layer provides a combined offset space over persistent and local history, but search navigation exposes unique prompt text rather than every physical history row. ## Non-goals This change does not rewrite stored history, change normal Up/Down browsing semantics, add fuzzy matching, or add persistent metadata for attachments in cross-session history. Search deduplication is deliberately scoped to the active Ctrl+R search session and uses exact prompt text, so case, whitespace, punctuation, and attachment-only differences are not normalized. ## Tradeoffs The implementation keeps search state in the existing composer and history state machines instead of adding a new cross-module controller. That keeps ownership local and testable, but it means the composer still coordinates visible search status, draft restoration, footer rendering, cursor placement, and match highlighting while `ChatComposerHistory` owns traversal, async fetch continuation, boundary clamping, and unique-result caching. Unique-result caching stores cloned `HistoryEntry` values so known matches can be revisited without cache lookups; this is simple and robust for interactive search sizes, but it is not a global history index. ## Architecture `ChatComposer` detects `Ctrl+R`, snapshots the current draft, switches the footer to `FooterMode::HistorySearch`, and routes search-mode keys before normal editing. Query edits call `ChatComposerHistory::search` with `restart = true`, which starts from the newest combined-history offset. Repeated `Ctrl+R` or Up searches older; Down searches newer through already discovered unique matches or continues the scan. Persistent history entries still arrive asynchronously through `on_entry_response`, where a pending search either accepts the response, skips a duplicate, or requests the next offset. The composer-facing pieces now live in `codex-rs/tui/src/bottom_pane/chat_composer/history_search.rs`, leaving `chat_composer.rs` responsible for routing and rendering integration instead of owning every search helper inline. `codex-rs/tui/src/bottom_pane/chat_composer_history.rs` remains the owner of stored history, combined offsets, async fetch state, boundary semantics, and duplicate suppression. Match highlighting is computed from the current composer text while search is active and disappears when the match is accepted. ## Observability There are no new logs or telemetry. The practical debug path is state inspection: `ChatComposer.history_search` tells whether the footer query is idle, searching, matched, or unmatched; `ChatComposerHistory.search` tracks selected raw offsets, pending persistent fetches, exhausted directions, and unique match cache state. If a user reports skipped or repeated results, first inspect the exact stored prompt text, the selected offset, whether an async persistent response is still pending, and whether a query edit restarted the search session. ## Tests The change is covered by focused `codex-tui` unit tests for opening search without previewing the latest entry, accepting and canceling search, no-match restoration, boundary clamping, footer hints, case-insensitive highlighting, local duplicate skipping, and persistent duplicate skipping through async responses. Snapshot coverage captures the footer-mode visual changes. Local verification used `just fmt`, `cargo test -p codex-tui history_search`, `cargo test -p codex-tui`, and `just fix -p codex-tui`.
Codex CLI (Rust Implementation)
We provide Codex CLI as a standalone, native executable to ensure a zero-dependency install.
Installing Codex
Today, the easiest way to install Codex is via npm:
npm i -g @openai/codex
codex
You can also install via Homebrew (brew install --cask codex) or download a platform-specific release directly from our GitHub Releases.
Documentation quickstart
- First run with Codex? Start with
docs/getting-started.md(links to the walkthrough for prompts, keyboard shortcuts, and session management). - Want deeper control? See
docs/config.mdanddocs/install.md.
What's new in the Rust CLI
The Rust implementation is now the maintained Codex CLI and serves as the default experience. It includes a number of features that the legacy TypeScript CLI never supported.
Config
Codex supports a rich set of configuration options. Note that the Rust CLI uses config.toml instead of config.json. See docs/config.md for details.
Model Context Protocol Support
MCP client
Codex CLI functions as an MCP client that allows the Codex CLI and IDE extension to connect to MCP servers on startup. See the configuration documentation for details.
MCP server (experimental)
Codex can be launched as an MCP server by running codex mcp-server. This allows other MCP clients to use Codex as a tool for another agent.
Use the @modelcontextprotocol/inspector to try it out:
npx @modelcontextprotocol/inspector codex mcp-server
Use codex mcp to add/list/get/remove MCP server launchers defined in config.toml, and codex mcp-server to run the MCP server directly.
Notifications
You can enable notifications by configuring a script that is run whenever the agent finishes a turn. The notify documentation includes a detailed example that explains how to get desktop notifications via terminal-notifier on macOS. When Codex detects that it is running under WSL 2 inside Windows Terminal (WT_SESSION is set), the TUI automatically falls back to native Windows toast notifications so approval prompts and completed turns surface even though Windows Terminal does not implement OSC 9.
codex exec to run Codex programmatically/non-interactively
To run Codex non-interactively, run codex exec PROMPT (you can also pass the prompt via stdin) and Codex will work on your task until it decides that it is done and exits. If you provide both a prompt argument and piped stdin, Codex appends stdin as a <stdin> block after the prompt so patterns like echo "my output" | codex exec "Summarize this concisely" work naturally. Output is printed to the terminal directly. You can set the RUST_LOG environment variable to see more about what's going on.
Use codex exec --ephemeral ... to run without persisting session rollout files to disk.
Experimenting with the Codex Sandbox
To test to see what happens when a command is run under the sandbox provided by Codex, we provide the following subcommands in Codex CLI:
# macOS
codex sandbox macos [--full-auto] [--log-denials] [COMMAND]...
# Linux
codex sandbox linux [--full-auto] [COMMAND]...
# Windows
codex sandbox windows [--full-auto] [COMMAND]...
# Legacy aliases
codex debug seatbelt [--full-auto] [--log-denials] [COMMAND]...
codex debug landlock [--full-auto] [COMMAND]...
Selecting a sandbox policy via --sandbox
The Rust CLI exposes a dedicated --sandbox (-s) flag that lets you pick the sandbox policy without having to reach for the generic -c/--config option:
# Run Codex with the default, read-only sandbox
codex --sandbox read-only
# Allow the agent to write within the current workspace while still blocking network access
codex --sandbox workspace-write
# Danger! Disable sandboxing entirely (only do this if you are already running in a container or other isolated env)
codex --sandbox danger-full-access
The same setting can be persisted in ~/.codex/config.toml via the top-level sandbox_mode = "MODE" key, e.g. sandbox_mode = "workspace-write".
In workspace-write, Codex also includes ~/.codex/memories in its writable roots so memory maintenance does not require an extra approval.
Code Organization
This folder is the root of a Cargo workspace. It contains quite a bit of experimental code, but here are the key crates:
core/contains the business logic for Codex. Ultimately, we hope this to be a library crate that is generally useful for building other Rust/native applications that use Codex.exec/"headless" CLI for use in automation.tui/CLI that launches a fullscreen TUI built with Ratatui.cli/CLI multitool that provides the aforementioned CLIs via subcommands.
If you want to contribute or inspect behavior in detail, start by reading the module-level README.md files under each crate and run the project workspace from the top-level codex-rs directory so shared config, features, and build scripts stay aligned.