clud

A fast Rust CLI for Claude Code and Codex that runs in YOLO mode by default — no permission prompts, maximum velocity.

The name clud is simply a shorter, easier-to-type version of claude.

Built in support for running codex on the claude harness:

clud --codex --harness claude

A /goal tuned for one task: solve it and push and merge the PR

clud do github.com/zackess/isssu/123

Grind down your bug list starting with the easy one

clud grind

CI builds each of the six target triples once on Linux and executes the result on native Linux/Windows/macOS runners — see docs/architecture/ci.md.

Installation

macOS / Linux

curl -fsSL https://raw.githubusercontent.com/zackees/clud/main/install.sh | sh

Windows (PowerShell)

irm https://raw.githubusercontent.com/zackees/clud/main/install.ps1 | iex

Both scripts install uv if needed, then uv tool install clud, and put clud on PATH for new shells. Pin a version with CLUD_VERSION=2.0.14 curl ... | sh (POSIX) or $env:CLUD_VERSION = '2.0.14'; irm ... | iex (PowerShell). Re-run to upgrade.

Already have a Python package manager? Any of these works equivalently:

uv tool install clud   # recommended — isolated, fast
pipx install clud      # equivalent if you already use pipx
pip install clud       # plain pip; you must ensure the install bin dir is on PATH

Usage

clud                              # Launch Claude in YOLO mode via subprocess
clud --codex                      # Use Codex as the backend
clud --claude                     # Use Claude as the backend (default)
clud --pty                        # Force PTY launch mode
clud --subprocess                 # Force subprocess launch mode
clud --pty --graphics=sixel       # Force a Sixel header above PTY output
clud --demo-gfx-sixel             # Render the README hero image as a Sixel demo
clud --detach -p "review this PR" # Start a daemon-managed session without attaching
clud --detachable -p "fix CI"     # Ctrl+C asks whether to keep the session in background
clud --transcript session.log -p "debug this" # Tee daemon session output to a file
clud -c                           # Continue the most recent conversation
clud --resume                     # Resume a session
clud --resume abc123              # Resume a specific session by ID or search term
clud -p "refactor the auth layer" # Run with a prompt, exit when done
clud -m "what does this do?"      # Send a one-off message
clud --model opus -p "review PR"  # Choose a model
clud --safe -p "drop the table"   # Disable YOLO mode (keeps permission prompts)
clud --dry-run -p "hello"         # Print what would run without executing
echo "explain this error" | clud  # Pipe mode: read prompt from stdin
clud -- --verbose --debug         # Pass extra flags through to the backend
clud attach                       # List background sessions you can reattach to
clud attach sess-123              # Attach to a specific session
clud list                         # Show background session IDs, PIDs, and cwd
clud wasm guest.wasm              # Run a local wasm module with clud's embedded runtime

Flags

Unknown flags are forwarded directly to the backend agent.

clud now defaults to subprocess launch mode for Claude and Codex. Use --pty to opt back into PTY while Claude PTY issues are being investigated.

PTY Graphics Headers

PTY sessions can reserve a small header area above the backend terminal and draw a Sixel image there. --graphics=auto is conservative: it only enables the header when running-process reports Sixel as supported from a live probe of the current terminal. Missing metadata, non-TTY attaches, blocked terminals, and host-name-only hints stay text-only. Use --graphics=off to disable the feature or --graphics=sixel to force it.

By default clud renders the bundled README hero image. Pass --graphics-image <PATH> to use a PNG or JPEG instead. Direct PTY launches reserve rows before the backend starts. Daemon-managed sessions decide at attach time, because the detached worker does not know which terminal will attach later; reattach and resize paths redraw the header where the terminal reports support.

Codex Support

The Rust version of clud supports Codex directly. Use --codex to switch backends for interactive runs, prompt-driven execution, resume flows, and detachable sessions.

Codex through Claude Code (experimental)

To use a Codex model with Claude Code's harness features, opt in explicitly:

clud --codex --harness claude
clud --codex --harness claude --model terra@high

Provider and harness are separate choices. --harness default restores the provider's native harness for one launch. An explicit session/global choice is offered interactively; global choices are stored in ~/.clud/settings.json. When a saved non-default harness is used on a TTY, clud prints a green [clud] Harness override: Claude (global setting) notice. CLI flags always override saved settings.

Use a platform API key by setting OPENAI_API_KEY in the launch environment. ChatGPT subscription login is experimental and compatibility-sensitive:

clud codex-auth login --acknowledge-experimental
clud codex-auth status
clud codex-auth logout

The subscription record is clud-owned and never falls back silently to an API key. logout removes only clud's record, not Codex CLI credentials.

Cross-route troubleshooting

• Claude executable missing: install Claude Code and ensure claude is on PATH. Use clud --codex --harness default while fixing the installation.
• Unsupported pair: only Codex provider through Claude is supported. Claude provider through Codex is rejected before launch.
• Login expired: run clud codex-auth login --acknowledge-experimental; do not expect an existing subscription record to fall back to an API key.
• Callback ports occupied: free 1455 or 1457, then retry login. The command uses 1455 first and 1457 only as its fallback.
• Bridge start or upstream failure: run clud --dry-run --codex --harness claude to inspect the resolved target. Check proxy/firewall rules permit the configured OpenAI endpoint; upstream 4xx errors usually require a credential, model, or request change, while transient 5xx/429 failures are retried only before output begins.
• Disable/rollback: pass --harness default or reset the stored harness in clud settings. Native clud, clud --claude, and clud --codex launches are unaffected.

Compatibility evidence, security boundaries, and the no-sidecar design live in the Codex-via-Claude architecture document.

Codex Hook Warnings

On clud --codex launches, clud runs a lightweight hook-health check before starting Codex. The check compares Claude Code and Codex PreToolUse hook coverage and inspects Codex hook trust state. These warnings are informational; normal launch continues unless the backend itself fails.

If Codex has PreToolUse hooks but Claude Code does not, clud prints:

[clud] warning: Codex PreToolUse hooks exist, but Claude PreToolUse hooks are missing or inactive. Run `clud --fix-hooks`.

Run clud --dry-run --fix-hooks to see the planned repair actions. Run clud --fix-hooks only when you want clud to add deterministic Codex trust entries or ask the selected backend to translate a missing hook between Claude Code and Codex.

Codex hook matchers may use * as a catch-all. When equivalent Claude Code hooks use the same command across several tool matchers, the Codex repair plan prefers one catch-all hook instead of repeated per-tool prompts. That reduces duplicate Codex hook review/trust approvals while keeping per-tool hooks when commands differ.

On Windows, Codex hook commands that call a .cmd or .bat wrapper need explicit exit-code propagation. If the command does not include $LASTEXITCODE, clud warns:

[clud] warning: Codex hook command in C:\Users\you\.codex\hooks.json uses a Windows batch wrapper without explicit `$LASTEXITCODE` propagation; a blocking hook may fail open.

Fix the hook by invoking a native executable directly, or by making the PowerShell hook command end with exit $LASTEXITCODE after the batch wrapper. Without that, a hook intended to block a tool call can return success to Codex after the wrapper fails.

Detached Sessions

Use daemon-managed sessions when you want to disconnect and reattach later.

clud --detachable --codex -p "refactor the parser"
# press Ctrl+C, then press y within 5 seconds to keep it running in background

clud attach
clud attach sess-123
clud list

If you press Ctrl+C in a --detachable session, clud asks continue session in the background? with a 5-second countdown. Press y to background it. Press Ctrl+C again, press anything else, or do nothing to end the session instead.

clud attach without a session ID lists background sessions. clud list shows the same sessions with their root PID and current working directory.

Daemon idle lifetime

The daemon starts on demand and, by default, exits after 15 minutes with no active work. This releases its GC database and background resources; the next normal daemon-backed command starts it again transparently. Active foreground clients, detached/repeat sessions, dashboard or top polling, RPC connections, and maintenance prevent this shutdown. Configure daemon.idle_timeout_secs in ~/.clud/settings.json to another positive number of seconds, or set it to 0 to disable idle retirement.

Voice Mode (F3 push-to-talk)

clud captures microphone input and transcribes it directly into the active backend prompt using local whisper.cpp. Hold F3, speak, release F3, and the transcript appears at your cursor without auto-submitting — you can edit it before pressing Enter. Available on all six supported platforms (Linux x86/ARM, Windows x86/ARM, macOS x86/ARM). On Linux, microphone capture uses arecord on demand so libasound is not required for normal startup.

Enabling it

The minimum is a single env var:

export CLUD_VOICE=1
clud

# Windows PowerShell
$env:CLUD_VOICE = "1"
clud

On first F3 press, clud auto-downloads the Whisper ggml-small.en.bin model (~466 MB) into a per-OS cache directory and verifies it against a pinned SHA-256. The download runs in the background as soon as voice mode starts up, so by the time you reach for F3 it's usually ready.

If you already have a model on disk, point CLUD_WHISPER_MODEL at it and the auto-download is skipped.

How F3 behaves on different terminals

Cues are short tones generated programmatically on macOS/Windows — ding on start (~880 Hz, 90 ms), dong on stop (~660 Hz, 120 ms). Linux uses a terminal bell so clud does not link audio output libraries at startup. If the default audio output device is unavailable, clud falls back to a terminal bell.

Environment variables

Troubleshooting

• Nothing happens when I press F3. Check that CLUD_VOICE=1 is exported in the same shell. On Linux, install alsa-utils so arecord is available, then verify a default input device exists (arecord -l on Linux, "Sound" preferences on macOS/Windows).
• "voice mode is enabled but the Whisper model is not yet available" — the auto-download hasn't finished. Watch stderr for [clud] voice: download N% (...) lines, or pre-seed the cache path manually with curl -L -o <cache-path> https://huggingface.co/ggerganov/whisper.cpp/resolve/main/ggml-small.en.bin.
• Recording keeps stopping mid-sentence on non-kitty terminals. The VAD silence window is 1.5 s — pause less, or switch to a kitty-protocol terminal for true hold-to-record.
• Transcript is empty / garbage. Whisper struggles on very short utterances and noisy backgrounds. The MIN_CAPTURE_MS floor (150 ms) silently drops sub-150 ms blips; speak for at least half a second.

clud loop — The Ralph Loop

Run the backend in a ralph loop: iterate on a task until the agent signals it's done, or until the iteration count runs out. Fully autonomous — no user interaction between iterations.

clud loop "Implement the API endpoints from the spec"
clud loop TASK.md                                  # Read prompt from a file
clud loop https://github.com/org/repo/issues/42    # Fetch & iterate on a GH issue
clud loop --loop-count 10 "fix bugs"               # Custom iteration count

In-chat /loop for Codex models

Codex does not ship a /loop command. clud used to fill that gap with a bundled clud-loop skill; it is retired as of the --harness claude cross-route. Run Codex models under the Claude harness and you get the harness's own /loop:

clud --codex --harness claude

Retiring it also fixes a mis-fire: the skill's triggers keyed on the word "Codex", so a Codex model driving the Claude harness would pick the polyfill over the harness's native /loop. clud purges the installed copy from both ~/.claude/skills/ and ~/.codex/skills/ on next launch, leaving any copy you edited yourself in place.

For a plain clud --codex session with no cross-route, the external runner is still there:

clud --codex loop .clud/loop/LOOP.md
clud --codex loop --repeat 30m --loop-count 1 --no-done .clud/loop/LOOP.md

Task input modes

The positional argument is classified in this order:

1. GH issue / PR URL — the issue body is fetched via gh and cached to <git-root>/.clud/loop/<owner>__<repo>__issue-<n>.md. Subsequent runs reuse the cache; pass --refresh to force a re-fetch.
2. Short form #42 — resolves owner/repo via gh repo view.
3. Local file path — read as the prompt.
4. Literal string — used as-is.

Completion signal (DONE / BLOCKED marker files)

clud loop injects a short contract into the prompt asking the agent to write one of two marker files under <git-root>/.clud/loop/:

Stale DONE / BLOCKED files from a prior run are cleared at start so the loop can't short-circuit on iteration 1.

Opt out with --no-done-marker to restore the old "run N times unless the backend fails" behavior.

clud rebase — Auto-Rebase

Fetches from origin, rebases the current branch, and resolves conflicts.

clud rebase

clud fix — Auto-Fix

Detects linting and test tools in your repo, runs them, and fixes failures in a loop until everything passes.

clud fix

clud up — Ship It

Runs lint, test, cleanup, then commits.

clud up

clud wasm — Embedded Runtime

Loads a local .wasm module, wires up a host logging import, and invokes an exported function.

clud wasm hello.wasm
clud wasm hello.wasm --invoke _start

Development

bash build                  # Build dev wheel (Rust binary + Python package)
bash lint                   # Lint (cargo fmt + clippy + ruff + banned imports)
bash test                   # Unit tests (Rust + Python)
bash test --integration     # Include integration tests with mock agents

License

Clud Proprietary License. Free use is available for individuals and organizations under 6 people, with lifetime grandfathering for organizations that qualified before growing beyond that size. Larger organizations need a commercial license unless they have a grandfathered or contributor-granted free license. See LICENSE for the full terms.