cccat turns Claude Code's idle moments — thinking, running tools, waiting for a response — into
tiny English-learning moments for developers whose first language isn't English. An animated
kaomoji cat sits in your status line reflecting what Claude Code is doing, and next to it shows
a practical English expression from real dev work, explained in your own language.

Explanations currently ship in Korean and Japanese, and the design makes adding more
languages a matter of dropping in one overlay file — the English expressions stay shared.

English expression + Korean explanation	English expression + Japanese explanation

_{Rendered from the real cccat status-line engine (cccat lang ko / cccat lang ja). The cat's
face and spinner animate in real time as Claude Code's activity changes; the state label
(thinking / Git / testing / success …) and the explanation both follow your chosen language. See
docs/VERIFICATION.md for a live Claude Code TUI capture.}

Table of contents

• Why
• At a glance
• Requirements
• Install
• Explanation languages
• Projects with their own status line
• Usage
• CLI reference
• Configuration
• Uninstall
• Privacy
• FAQ
• Docs
• License

Why

Using Claude Code, you spend a lot of little moments waiting for a response. The idea is to turn
those few seconds into learning real, everyday developer English — expressions like
stage the changes, cover the edge case, clean build — instead of scrolling away. It runs
100% locally, makes zero network requests, and never stores your prompts or file contents.

At a glance

Requirements

• Node.js 18+ (npx ships with Node)
• Claude Code (verified on 2.1.201 / macOS — see docs/COMPATIBILITY.md)

Install

Option 1 — npx (easiest, nothing to clone)

npx github:dkdannyboy/cccat install

One line, no clone and no global install. Remove later with npx github:dkdannyboy/cccat uninstall.

Option 2 — one-line install script

curl -fsSL https://raw.githubusercontent.com/dkdannyboy/cccat/main/scripts/install.sh | sh

Clones (or updates) the repo into ~/.cccat/app and runs cccat install.

Option 3 — clone (for development / contributing)

git clone https://github.com/dkdannyboy/cccat.git
cd cccat
node bin/cccat.js install     # or: npm install -g . && cccat install

Restart Claude Code after installing and the cat appears in your status line.

What install does

• Backs up ~/.claude/settings.json to ~/.cccat/backup/ with a timestamp
• Copies its own source into ~/.cccat/app so hooks reference a stable path (an npx cache path
  would otherwise break once cleaned)
• If you already have a status line, it is never removed — cccat wraps it so your existing
  output always shows first, with the cccat lines below it (your original output is cached for 5s)
• Registers 9 hook events (UserPromptSubmit, PreToolUse, PostToolUseFailure, Stop,
  Notification, SubagentStart, SubagentStop, SessionStart, SessionEnd) — your existing
  hooks are untouched. For performance it does not register the per-tool-call PostToolUse, and
  throttles PreToolUse to skip redundant runs within 2s
• Sets a status line refreshInterval (1s by default) so the animation keeps moving between
  events. Turning animation off (config show_animation false) removes the timer entirely
• Uses a launcher that resolves node at run time, so upgrading Node later won't break the hooks
• Reinstalling is safe (idempotent) — no duplicate lines

Explanation languages

The default explanation language is Korean; Japanese is fully supported (all 240+ expressions
translated). Switch at any time:

cccat lang ja     # Japanese explanations
cccat lang ko     # back to Korean
cccat lang        # show current + supported languages

Changes apply immediately — no reinstall. Meanings, examples and quiz hints all follow the
chosen language. Only the explanation is translated; the English expressions are shared across
all languages. Adding a language is just a content/i18n/<code>.json overlay — see
docs/CONTENT_GUIDE.md. Contributions of new
language overlays are welcome.

The optional danielclass.com note (free English study material) is
shown only to Korean-language users, at most once a day.

Projects with their own status line

Some projects define their own status line in .claude/settings.json. Since project settings
take precedence over user settings, cccat is hidden inside such a project. Run this once in
that project's directory to make them coexist:

cccat adopt      # show the project's status line + the cccat lines together
cccat unadopt    # revert

adopt only writes to the git-ignored .claude/settings.local.json and never touches the
shared .claude/settings.json. cccat doctor detects this situation and suggests the command.

Usage

After installing it just works. The status line follows what Claude Code is doing (thinking /
reading / writing / testing / git / error …), changing the cat's face and the English
expression. The expression rotates about every 30s (default), and previously seen expressions
come back later as review via a spaced-repetition schedule.

Preview without installing:

cccat demo thinking

CLI reference

Configuration

Change with cccat config set <key> <value>. Defaults live in lib/config.js.

Uninstall

cccat uninstall           # restore status line/hooks, keep learning data
cccat uninstall --purge   # the above + delete all of ~/.cccat

Privacy

100% local, zero network requests. It stores only: tool type, file extension, command category,
keyword-matched tags, and learning history. It never stores prompt text, file contents, full
paths, environment variables, or secrets. See docs/PRIVACY.md or run
cccat privacy.

FAQ

Does it slow Claude Code down?
Not noticeably. Each tool call adds ~80ms via the PreToolUse hook (mostly Node cold-start), and
consecutive calls skip even that thanks to a 2s throttle. Hooks are designed to exit quietly on
any input, so they never block Claude Code.

Does it use a lot of CPU/battery?
The status line re-runs every refresh_sec (1s default) for the animation (~0.1s CPU per call).
Reduce it with cccat config set refresh_sec 3 or remove the timer entirely with
cccat config set show_animation false, then cccat install.

Where do the expressions come from? Is it generated live by AI?
240+ curated expressions ship locally, so it works with no external API. There are no live LLM
calls (hence zero network, zero cost). Add your own via a user pack (below).

I already use a status line.
Install wraps your existing status line command; its output always shows on the first line, then
the cccat lines follow. Nothing is removed.

A project defines its own status line.
Run cccat adopt once in that project directory —
see Projects with their own status line.

Can I get explanations in another language?
Korean and Japanese today. Adding a language is a single overlay file
(docs/CONTENT_GUIDE.md); PRs welcome.

Can I add my own expressions?
Drop a pack into ~/.cccat/packs/*.json and it loads alongside the core pack. Schema in
docs/CONTENT_GUIDE.md.

Docs

Contributing

Bug reports and expression suggestions are welcome — open an issue or PR. Run tests with
npm test; PRs must pass CI (Node 18/20/22 × Linux/macOS). New language overlays especially
welcome.

License

MIT — LICENSE