78e8ee4591
## Problem
When the TUI connects to a **remote** app-server (via WebSocket), resume
and fork operations lost all conversation history.
`AppServerStartedThread` carried only the `SessionConfigured` event, not
the full `Thread` snapshot. After resume or fork, the chat transcript
was empty — prior turns were silently discarded.
A secondary issue: `primary_session_configured` was not cleared on
reset, causing stale session state after reconnection.
## Approach: TUI-side only, zero app-server changes
The app-server **already returns** the full `Thread` object (with
populated `turns: Vec<Turn>`) in its `ThreadStartResponse`,
`ThreadResumeResponse`, and `ThreadForkResponse`. The data was always
there — the TUI was simply throwing it away. The old
`AppServerStartedThread` struct only kept the `SessionConfiguredEvent`,
discarding the rich turn history that the server had already provided.
This PR fixes the problem entirely within `tui_app_server` (3 files
changed, 0 changes to `app-server`, `app-server-protocol`, or any other
crate). Rather than modifying the server to send history in a different
format or adding a new endpoint, the fix preserves the existing `Thread`
snapshot and replays it through the TUI's standard event pipeline —
making restored sessions indistinguishable from live ones.
## Solution
Add a **thread snapshot replay** path. When the server hands back a
`Thread` object (on start, resume, or fork),
`restore_started_app_server_thread` converts its historical turns into
the same core `Event` sequence the TUI already processes for live
interactions, then replays them into the event store so the chat widget
renders them.
Key changes:
- **`AppServerStartedThread` now carries the full `Thread`** —
`started_thread_from_{start,resume,fork}_response` clone the thread into
the struct alongside the existing `SessionConfiguredEvent`.
- **`thread_snapshot_events()`** walks the thread's turns and items,
producing `TurnStarted` → `ItemCompleted`* →
`TurnComplete`/`TurnAborted` event sequences that the TUI already knows
how to render.
- **`restore_started_app_server_thread()`** pushes the session event +
history events into the thread channel's store, activates the channel,
and replays the snapshot — used for initial startup, resume, and fork.
- **`primary_session_configured` cleared on reset** to prevent stale
session state after reconnection.
## Tradeoffs
- **`Thread` is cloned into `AppServerStartedThread`**: The full thread
snapshot (including all historical turns) is cloned at startup. For
long-lived threads this could be large, but it's a one-time cost and
avoids lifetime gymnastics with the response.
## Tests
- `restore_started_app_server_thread_replays_remote_history` —
end-to-end: constructs a `Thread` with one completed turn, restores it,
and asserts user/agent messages appear in the transcript.
- `bridges_thread_snapshot_turns_for_resume_restore` — unit: verifies
`thread_snapshot_events` produces the correct event sequence for
completed and interrupted turns.
## Test plan
- [ ] Verify `cargo check -p codex-tui-app-server` passes
- [ ] Verify `cargo test -p codex-tui-app-server` passes
- [ ] Manual: connect to a remote app-server, resume an existing thread,
confirm history renders in the chat widget
- [ ] Manual: fork a thread via remote, confirm prior turns appear
|
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|---|---|---|
| .. | ||
| .cargo | ||
| .config | ||
| .github/workflows | ||
| ansi-escape | ||
| app-server | ||
| app-server-client | ||
| app-server-protocol | ||
| app-server-test-client | ||
| apply-patch | ||
| arg0 | ||
| artifacts | ||
| async-utils | ||
| backend-client | ||
| chatgpt | ||
| cli | ||
| cloud-requirements | ||
| cloud-tasks | ||
| cloud-tasks-client | ||
| codex-api | ||
| codex-backend-openapi-models | ||
| codex-client | ||
| codex-experimental-api-macros | ||
| config | ||
| connectors | ||
| core | ||
| debug-client | ||
| docs | ||
| exec | ||
| execpolicy | ||
| execpolicy-legacy | ||
| feedback | ||
| file-search | ||
| hooks | ||
| keyring-store | ||
| linux-sandbox | ||
| lmstudio | ||
| login | ||
| mcp-server | ||
| network-proxy | ||
| ollama | ||
| otel | ||
| package-manager | ||
| process-hardening | ||
| protocol | ||
| responses-api-proxy | ||
| rmcp-client | ||
| scripts | ||
| secrets | ||
| shell-command | ||
| shell-escalation | ||
| skills | ||
| state | ||
| stdio-to-uds | ||
| test-macros | ||
| tui | ||
| tui_app_server | ||
| utils | ||
| vendor | ||
| windows-sandbox-rs | ||
| .gitignore | ||
| BUILD.bazel | ||
| Cargo.lock | ||
| Cargo.toml | ||
| clippy.toml | ||
| config.md | ||
| default.nix | ||
| deny.toml | ||
| node-version.txt | ||
| README.md | ||
| rust-toolchain.toml | ||
| rustfmt.toml | ||
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. 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.