Agent IDE — Codex fork for AI-native development environment
c4f1af7a86
## Summary Adds syntax highlighting to the TUI for fenced code blocks in markdown responses and file diffs, plus a `/theme` command with live preview and persistent theme selection. Uses syntect (~250 grammars, 32 bundled themes, ~1 MB binary cost) — the same engine behind `bat`, `delta`, and `xi-editor`. Includes guardrails for large inputs, graceful fallback to plain text, and SSH-aware clipboard integration for the `/copy` command. <img width="1554" height="1014" alt="image" src="https://github.com/user-attachments/assets/38737a79-8717-4715-b857-94cf1ba59b85" /> <img width="2354" height="1374" alt="image" src="https://github.com/user-attachments/assets/25d30a00-c487-4af8-9cb6-63b0695a4be7" /> ## Problem Code blocks in the TUI (markdown responses and file diffs) render without syntax highlighting, making it hard to scan code at a glance. Users also have no way to pick a color theme that matches their terminal aesthetic. ## Mental model The highlighting system has three layers: 1. **Syntax engine** (`render::highlight`) -- a thin wrapper around syntect + two-face. It owns a process-global `SyntaxSet` (~250 grammars) and a `RwLock<Theme>` that can be swapped at runtime. All public entry points accept `(code, lang)` and return ratatui `Span`/`Line` vectors or `None` when the language is unrecognized or the input exceeds safety guardrails. 2. **Rendering consumers** -- `markdown_render` feeds fenced code blocks through the engine; `diff_render` highlights Add/Delete content as a whole file and Update hunks per-hunk (preserving parser state across hunk lines). Both callers fall back to plain unstyled text when the engine returns `None`. 3. **Theme lifecycle** -- at startup the config's `tui.theme` is resolved to a syntect `Theme` via `set_theme_override`. At runtime the `/theme` picker calls `set_syntax_theme` to swap themes live; on cancel it restores the snapshot taken at open. On confirm it persists `[tui] theme = "..."` to config.toml. ## Non-goals - Inline diff highlighting (word-level change detection within a line). - Semantic / LSP-backed highlighting. - Theme authoring tooling; users supply standard `.tmTheme` files. ## Tradeoffs | Decision | Upside | Downside | | ------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- | | syntect over tree-sitter / arborium | ~1 MB binary increase for ~250 grammars + 32 themes; battle-tested crate powering widely-used tools (`bat`, `delta`, `xi-editor`). tree-sitter would add ~12 MB for 20-30 languages or ~35 MB for full coverage. | Regex-based; less structurally accurate than tree-sitter for some languages (e.g. language injections like JS-in-HTML). | | Global `RwLock<Theme>` | Enables live `/theme` preview without threading Theme through every call site | Lock contention risk (mitigated: reads vastly outnumber writes, single UI thread) | | Skip background / italic / underline from themes | Terminal BG preserved, avoids ugly rendering on some themes | Themes that rely on these properties lose fidelity | | Guardrails: 512 KB / 10k lines | Prevents pathological stalls on huge diffs or pastes | Very large files render without color | ## Architecture ``` config.toml ─[tui.theme]─> set_theme_override() ─> THEME (RwLock) │ ┌───────────────────────────────────────────┘ │ markdown_render ─── highlight_code_to_lines(code, lang) ─> Vec<Line> diff_render ─── highlight_code_to_styled_spans(code, lang) ─> Option<Vec<Vec<Span>>> │ │ (None ⇒ plain text fallback) │ /theme picker ─── set_syntax_theme(theme) // live preview swap ─── current_syntax_theme() // snapshot for cancel ─── resolve_theme_by_name(name) // lookup by kebab-case ``` Key files: - `tui/src/render/highlight.rs` -- engine, theme management, guardrails - `tui/src/diff_render.rs` -- syntax-aware diff line wrapping - `tui/src/theme_picker.rs` -- `/theme` command builder - `tui/src/bottom_pane/list_selection_view.rs` -- side content panel, callbacks - `core/src/config/types.rs` -- `Tui::theme` field - `core/src/config/edit.rs` -- `syntax_theme_edit()` helper ## Observability - `tracing::warn` when a configured theme name cannot be resolved. - `Config::startup_warnings` surfaces the same message as a TUI banner. - `tracing::error` when persisting theme selection fails. ## Tests - Unit tests in `highlight.rs`: language coverage, fallback behavior, CRLF stripping, style conversion, guardrail enforcement, theme name mapping exhaustiveness. - Unit tests in `diff_render.rs`: snapshot gallery at multiple terminal sizes (80x24, 94x35, 120x40), syntax-highlighted wrapping, large-diff guardrail, rename-to-different-extension highlighting, parser state preservation across hunk lines. - Unit tests in `theme_picker.rs`: preview rendering (wide + narrow), dim overlay on deletions, subtitle truncation, cancel-restore, fallback for unavailable configured theme. - Unit tests in `list_selection_view.rs`: side layout geometry, stacked fallback, buffer clearing, cancel/selection-changed callbacks. - Integration test in `lib.rs`: theme warning uses the final (post-resume) config. ## Cargo Deny: Unmaintained Dependency Exceptions This PR adds two `cargo deny` advisory exceptions for transitive dependencies pulled in by `syntect v5.3.0`: | Advisory | Crate | Status | |----------|-------|--------| | RUSTSEC-2024-0320 | `yaml-rust` | Unmaintained (maintainer unreachable) | | RUSTSEC-2025-0141 | `bincode` | Unmaintained (development ceased; v1.3.3 considered complete) | **Why this is safe in our usage:** - Neither advisory describes a known security vulnerability. Both are "unmaintained" notices only. - `bincode` is used by syntect to deserialize pre-compiled syntax sets. Again, these are **static vendored artifacts** baked into the binary at build time. No user-supplied bincode data is ever deserialized. - Attack surface is zero for both crates; exploitation would require a supply-chain compromise of our own build artifacts. - These exceptions can be removed when syntect migrates to `yaml-rust2` and drops `bincode`, or when alternative crates are available upstream. |
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| .codex/skills/test-tui | ||
| .devcontainer | ||
| .github | ||
| .vscode | ||
| codex-cli | ||
| codex-rs | ||
| docs | ||
| patches | ||
| scripts | ||
| sdk/typescript | ||
| shell-tool-mcp | ||
| third_party | ||
| .bazelignore | ||
| .bazelrc | ||
| .bazelversion | ||
| .codespellignore | ||
| .codespellrc | ||
| .gitignore | ||
| .markdownlint-cli2.yaml | ||
| .npmrc | ||
| .prettierignore | ||
| .prettierrc.toml | ||
| AGENTS.md | ||
| announcement_tip.toml | ||
| BUILD.bazel | ||
| CHANGELOG.md | ||
| cliff.toml | ||
| defs.bzl | ||
| flake.lock | ||
| flake.nix | ||
| justfile | ||
| LICENSE | ||
| MODULE.bazel | ||
| MODULE.bazel.lock | ||
| NOTICE | ||
| package.json | ||
| pnpm-lock.yaml | ||
| pnpm-workspace.yaml | ||
| rbe.bzl | ||
| README.md | ||
| SECURITY.md | ||
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 want the desktop app experience, run
codex app or visit the Codex App page.
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:
# Install using npm
npm install -g @openai/codex
# Install using Homebrew
brew install --cask codex
Then simply run codex to get started.
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.
Docs
This repository is licensed under the Apache-2.0 License.