One skill library. Every project gets only what it needs.
Kitter is a desktop app and CLI for managing Agent Skills across projects. Keep your skills in one library, install the right combination for each project, and update them in one place.
Built entirely in Rust with GPUI, Kitter pairs a clean, responsive interface with instant startup, microscopic memory usage, and 60+ FPS native performance even when managing hundreds of skills.
- Maintain once, zero drift — Projects link directly to maintained skill sources via managed links (symlinks/junctions). Update a skill once, and every project reflects the change immediately.
- 15+ built-in agents and open plugin engine — Out-of-the-box support for mainstream AI coding agents, powered by an embedded QuickJS engine. Add or override any agent using simple single-file JavaScript plugins.
- Effective skills and token cost auditing — Automatically inspect project, parent directory, user-level, and plugin capabilities. Estimate prompt context token consumption per agent to keep your context lean.
- Presets and non-destructive AGENTS.md — Bundle curated skills and instruction rules into reusable presets. Injects instructions into
AGENTS.mdinside managed comment blocks without touching user notes. - Multi-source import and adoption — Add skills from GitHub, skills.sh-compatible sources, Claude plugins, or local directories. Use
adoptto scan and manage scattered pre-existing skills in place. - Native performance — 100% Rust with a lightweight GPUI desktop interface and a dedicated standalone CLI built for terminals and CI automation.
Kitter natively respects the distinctive discovery rules, target directories, frontmatter schemas, and catalog token estimation formats of each agent:
| Category | Agents / Platforms |
|---|---|
| Built-in Support | Claude Code · Cursor · Codex · OpenCode · GitHub Copilot · Antigravity · Grok · Pi · Oh My Pi (omp) · DimAgent · OpenClaw · Hermes · Droid · Amp · Trae |
| Universal Target | .agents/skills (standard multi-agent shared directory) |
| Custom Plugins | Extendable to any proprietary or emerging agent via lightweight JavaScript plugins |
Easily define support for custom in-house agents or community tools (see the Agent Plugins Guide):
import { defineAgent, standard } from "kitter";
export default defineAgent({
apiVersion: 1,
id: "my-agent",
name: "My Agent",
reads: ["my-agent", "universal"],
install: { project: ".my-agent/skills", global: "~/.my-agent/skills" },
skills: standard.skills({
project: [".my-agent/skills", ".agents/skills"],
user: ["~/.my-agent/skills", "~/.agents/skills"],
}),
});Manage agents directly from desktop Settings or via kitter agents (add, remove, update, enable/disable, and reorder).
Download the prebuilt application from GitHub Releases:
- macOS (Apple Silicon / Intel) — choose
macos-arm64.dmg(Apple Silicon) ormacos-x86_64.dmg(Intel), open the.dmgand dragKitter.appintoApplications. (If macOS blocks first launch, confirm it was downloaded from the official release, then go to System Settings → Privacy & Security → Open Anyway, or runxattr -dr com.apple.quarantine /Applications/Kitter.app) - Windows (x64) — download
Kitter-<version>-desktop-windows-x86_64.exeand run it directly (statically linked MSVC runtime, zero dependencies). - Linux (x64) — extract
Kitter-<version>-desktop-linux-x86_64.tar.gzand run./Kitterfrom the extracted directory.
Standalone CLI: The desktop app and CLI share the same core but are released as separate artifacts. Standalone
kitterCLI binaries for macOS, Windows, and Linux are available directly on the Releases page.
Use + to add skills from a local folder, GitHub or a skills.sh-compatible source, or a Claude plugin source. If skills are already scattered across projects, choose Existing installations to inspect and adopt them without moving their source directories.
Kitter keeps one maintained source for each skill. Open its Installs tab to immediately see every project using it, every installation location, and the agents that can discover it.
Select a skill, choose a project, then install it into the shared .agents/skills directory or an agent-specific directory. Kitter creates managed links instead of independent copies, so projects can use different combinations without creating update drift. Skills you use across all projects can also be installed at the user level.
Open Projects to see the complete effective skill set for every agent—not just installations managed by Kitter. The view discovers project, parent, user-level, built-in, and plugin-provided capabilities, then shows where each one came from.
The per-agent token estimate helps you spot skills that add unnecessary context overhead.
A preset bundles skills with optional AGENTS.md instructions. Open Presets to build one, then install it into a project in one step. Kitter appends the preset's instructions to the project's AGENTS.md inside a managed block and leaves your own content untouched.
When you change a preset, its projects show that they need a sync, and you choose when to apply it. Removing a preset from a project removes only what it installed.
kitter preset create frontend
kitter preset add frontend react typescript
kitter preset install frontend --project /path/to/project --target universal
kitter preset sync frontendRun Check for updates from the desktop app or use kitter check and kitter update. Every managed project continues to use the same maintained source.
# 1. Skill Library Management
kitter add npx https://github.com/owner/repository --skill skill-a # Add skill from repository
kitter list # List managed skills
kitter update --all # Update all skills
kitter adopt --all # Discover & adopt scattered skills
# 2. Project Installation
kitter install skill-a --project /path/to/project --target universal # Install to project
kitter project /path/to/project # Inspect effective skills & tokens
kitter uninstall skill-a --project /path/to/project # Remove skill installation
# 3. Presets
kitter preset create frontend # Create a preset
kitter preset add frontend react typescript # Add skills to preset
kitter preset install frontend --project /path/to/project # Install preset to project
kitter preset sync frontend # Sync preset changes
# 4. Agent Plugins Management
kitter agents # List agents & plugin health
kitter agents add https://github.com/owner/repo # Add agent plugin from git
kitter agents enable <id> / disable <id> # Enable or disable an agent
kitter agents move <id> --before <other-id> # Reorder agentsYou do not need the desktop app to use Kitter. Download the standalone CLI from GitHub Releases, put kitter on your PATH, and install the $kitter skill directly:
npx skills add what1f/kitter --skill kitterThe skill lets an agent inspect the current machine, add or adopt skill sources, install the right project combination, and verify the result through the standalone kitter CLI. If the CLI is missing, the skill can guide you through downloading it from an official Release.
Kitter stores configuration and source records in the operating system's application-data directory. Skill contents live in the library directory:
| Platform | Default skill library |
|---|---|
| macOS | ~/Library/Application Support/Kitter/skills |
| Windows | %LOCALAPPDATA%\Kitter\skills |
| Linux | $XDG_DATA_HOME/Kitter/skills or ~/.local/share/Kitter/skills |
View or change the location with kitter library and kitter library --set /absolute/path.
Build instructions
git clone https://github.com/what1f/kitter.git
cd kitter
# Launch desktop app
cargo run --release --locked --features desktop --bin kitter-desktop
# Build standalone CLI
cargo build --release --locked --bin kitterIssues and pull requests are welcome. Please open an issue before starting a large behavioral or UI change so the scope can be aligned first.
If Kitter makes your skill setup calmer, consider starring the repository. It helps more multi-project developers find it.
Kitter is available under the Apache License 2.0. Licenses for bundled fonts, icons, and other third-party material are listed in THIRD_PARTY_LICENSES.md.