# Sunder

> Sunder is an open-source desktop app where people install and build native tools as packages.

Sunder serves users who want installable desktop tools, AI agent users who want local tool-backed agents, vibecoders who want Agent Builder to help create packages, and developers who want to build, validate, and publish Sunder packages. Public Sunder repositories are licensed under the GNU General Public License version 3.

## Canonical Product Entities

- Sunder App: the cross-platform desktop app where users install, manage, and use packages.
- Sunder Runtime Host: the local process that owns installed package state, validation, activation, configuration, secrets, faults, and package assets.
- Sunder Registry: the public package catalog and distribution site where users discover packages and developers publish package versions.
- Sunder package: an installable tool made for Sunder. Packages can add panels, dashboards, commands, automations, integrations, AI agents, settings, background services, native desktop features, and local workflows.
- Sunder Agent: a first-party Sunder package family for AI chat sessions, model providers, file tools, shell tools, web tools, MCP integrations, skills, memory, subagents, local or Docker execution, and Agent Builder.
- Sunder Agent Builder: an Agent extension for creating, editing, building, and testing Sunder packages from inside Sunder App.

## Important Pages

- [Product overview and downloads](https://sunderapp.io/): Sunder App overview, platform downloads, examples of installable desktop tools, package model, Agent Builder, and public repositories.
- [Sunder Agent](https://sunderapp.io/agent): AI agent package family, model providers, file and shell tools, web tools, MCP, skills, memory, subagents, execution targets, and Agent Builder.
- [Package author page](https://sunderapp.io/developers): Developer and vibecoder overview for building desktop tools as Sunder packages instead of standalone apps.
- [Developer docs](https://sunderapp.io/docs): SDK, CLI, Runtime Host, package standard, Registry workflow, and troubleshooting documentation.
- [Public package Registry](https://hub.sunderapp.io/): Public Sunder package catalog and package distribution site.
- [Sunder Agent package](https://hub.sunderapp.io/packages/sunder.package.agent): Registry package detail page for the Sunder Agent core package.

## Repositories

- [Sunder Core](https://github.com/Younics/sunder-core): Desktop app, Runtime Host, CLI, SDK, package templates, package tooling, archive validation, and public Registry contracts.
- [Sunder Agent](https://github.com/Younics/sunder-agent-package): First-party Agent package family source repository.
- [GNU GPLv3 license](https://raw.githubusercontent.com/Younics/sunder-core/refs/heads/main/LICENSE): Public Sunder repository license text.

## Key Workflows

- Users download Sunder App for Windows, macOS, or Linux, then browse Sunder Registry and install packages into the local runtime.
- Packages can become dashboards, file utilities, command buttons, API panels, automations, hardware controls, AI tools, local model workflows, and custom native desktop panels.
- Sunder App manages package lifecycle tasks such as install, update, enable, disable, uninstall, and readiness inspection.
- Sunder Agent users install `sunder.package.agent`, add model providers, file tools, shell tools, web tools, MCP, memory, subagents, execution targets, or Builder, configure an Agent profile, and start sessions inside Sunder App.
- Sunder Agent Builder can help create, edit, build, and test Sunder packages from inside Sunder App.
- Package authors create a package from templates, run `dotnet build` for a `sunder-dev` folder, run `dotnet publish` for a `.sunderpkg` archive, validate it with the Sunder CLI, and publish it to Sunder Registry.
- Sunder is not a window manager. It does not arrange arbitrary OS windows or embed random external apps. Sunder packages are built for Sunder and run inside Sunder App.

## Common Agent Package IDs

- `sunder.package.agent`: Agent core package.
- `sunder.package.agent.provider.openai`: OpenAI model provider package.
- `sunder.package.agent.provider.anthropic`: Anthropic model provider package.
- `sunder.package.agent.provider.gemini`: Gemini model provider package.
- `sunder.package.agent.provider.lmstudio`: LM Studio local model provider package.
- `sunder.package.agent.tools.files`: Workspace file tools package.
- `sunder.package.agent.tools.shell`: Workspace shell tools package.
- `sunder.package.agent.tools.web`: Web search and URL fetch tools package.
- `sunder.package.agent.mcp`: Model Context Protocol integration package.
- `sunder.package.agent.skills`: Skills import package.
- `sunder.package.agent.subagents`: Specialist subagent package.
- `sunder.package.agent.memory.semantic`: Semantic memory package.
- `sunder.package.agent.execution.local`: Local machine execution package.
- `sunder.package.agent.execution.docker`: Docker-backed execution package.
- `sunder.package.agent.builder`: Sunder package development session controls for Sunder Agent.

## Optional

- [Community Discord](https://discord.gg/wwGq4JH56r): Sunder community and development discussion.
- [Backing organization](https://younics.com): Younics website.