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tweakcc

Updated Jul 7, 2026

A CLI tool by Piebald AI that patches an existing Claude Code installation — npm or native binary — with custom system prompts, color themes, thinking verbs, spinner animations, custom toolsets, user-message styling, subagent model overrides, session memory, a /remember skill, table format switching, and MCP startup optimization. Run npx tweakcc, configure via the interactive menu or ~/.tweakcc/config.json, and apply with --apply. Community patches installable from a URL via tweakcc adhoc-patch.

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What it does

npx tweakcc
Launch the interactive configuration menu to set up themes, thinking verbs, spinners, toolsets, and system prompt patches.
npx tweakcc --apply
Reapply all saved customizations from ~/.tweakcc/config.json after a Claude Code update.
npx tweakcc adhoc-patch --url <url>
Download and apply a custom patch script from a URL without installing a separate npm package.
npx tweakcc unpack / repack
Extract the cli.js from a native binary installation, edit it, and repack it into the binary.
/toolset
In Claude Code, switch to a custom toolset defined in the tweakcc configuration.
/remember
Persist a fact or context note across Claude Code sessions (requires session memory feature enabled).

Files (1)

OVERVIEW.mdprimary · markdown · 2.0 KB

## What it does

tweakcc patches Claude Code's compiled cli.js (or native binary on macOS/Windows/Linux) with customizations stored in ~/.tweakcc/config.json. Supports npm-based and native binary installations, including Homebrew, nvm, fnm, volta, and Nix. After a Claude Code update overwrites the patches, running npx tweakcc --apply reapplies everything from the config file.

Features available in tweakcc 4.0.0:

- Custom system prompts: edit any of Claude Code's 515+ internal prompt strings as markdown files and patch them in (with diff/conflict management vs. Anthropic's changes)
- Themes: graphical HSL/RGB color picker to restyle every UI color; switch themes with /config
- Thinking verbs: custom words shown while Claude works ("pondering", "considering")
- Spinner animations: custom animations with configurable speed and phase
- Toolsets: define custom toolsets invokable with /toolset in a session
- Session memory and /remember skill: persist facts across sessions (opt-in)
- Subagent model overrides: configure which model each sub-agent (Plan, Explore, general) uses
- User message styling: style the gray user-message text in chat history
- Table format switching: Claude Code default, Unicode (┌─┬─┐), ASCII/markdown (|---|), or borderless
- MCP startup optimization: non-blocking parallel MCP connections, ~50% faster startup
- Opus Plan 1M mode: opusplan[1m] alias — Opus for planning, Sonnet's 1M context for execution
- Input pattern highlighters: highlight custom strings (like "ultrathink") in the input box
- AGENTS.md support, auto-accept plan mode, token count rounding, context limit control

## Install

    npx tweakcc         # interactive setup
    pnpm dlx tweakcc    # alternative

Apply community patches from a URL:

    npx tweakcc adhoc-patch --url https://gist.github.com/...

## When to use

Use when you want to customize Claude Code's UI, system prompts, or behavior without forking the source — and you want customizations to survive Claude Code updates by reapplying from a config file.