atelier

Atelier is an offline, headless pixel-art editor for command-line tools and AI agents. Create layered sprites and animations, inspect pixels, and export PNGs, spritesheets, GIFs, APNGs, and TrueType pixel fonts. Documents stay local.

Use it directly from a shell or connect an agent through MCP (Model Context Protocol). Both interfaces expose the same editing tools; no graphical editor or running server is needed for CLI calls.

Showcase

• Animation showcase — compare models and briefs, view animations, and download replays.

• Frayed

Related MCP server: mnehmos.aseprite.mcp

Get started

Atelier builds from source on Linux or macOS with Rust 1.98+ and a native build toolchain. A container image is published for MCP clients; no native binaries are.

cargo install --locked --git https://github.com/marmikshah/atelier atelier
atelier --help

To work from a checkout instead, which also pins the Rust version used for development:

git clone https://github.com/marmikshah/atelier.git
cd atelier
cargo install --locked --path crates/atelier

Then follow your first sprite to create a document, draw pixels, and save an image. atelier uninstall removes it again, keeping your documents unless you ask otherwise.

Connect an agent

Agents with shell access can call atelier call TOOL '<json>' directly. For an MCP client, register atelier as a stdio server with no arguments:

{
  "mcpServers": {
    "atelier": {
      "command": "atelier",
      "env": { "ATELIER_HOME": "/absolute/path/to/your/art" }
    }
  }
}

In Claude Code, claude mcp add atelier -e ATELIER_HOME=/absolute/path/to/your/art -- atelier registers the same server. Then run atelier skills install --for claude (or codex, cursor, all) to give the agent the bundled drawing guides. Running Atelier covers HTTP, Docker, and storage.

Stability

Atelier is at 0.1. master is the current source; releases are dispatched from it and publish the container image, a vX.Y.Z tag, and the MCP Registry entry.

• Your documents are not discarded. Edits are journaled and committed atomically. A document that is damaged, or saved by a build with a different document schema, is refused with an error and left unchanged on disk.

• The document format is versioned, with no migration. If an update changes it, documents saved before it are refused, stay on disk untouched, and open again with the commit that wrote them.

• A recipe is the plain log of the calls that built a document, one JSON line each. It has no version of its own: what it draws depends on how the tools behave, so a recipe from one commit replays exactly on commits whose tools draw the same way.

• Tool names and arguments can still change between commits. Pin a commit if you script against them, and read the current surface from atelier tools --markdown.

How it is built

100% of this code was written by AI. Atelier began as an experiment in whether agents, using only tool calls, can make art useful in games. My part has been giving direction, and I hope the result helps you make something of your own.

CI checks formatting, strict Clippy, and the Rust test suite on Linux and macOS, smoke-tests the container, and replays every showcase recipe, which must reproduce its GIF byte for byte. The security policy describes the network and file-access boundaries.

Contributing

Bug reports and questions are welcome as issues; include the checkout commit and a minimal command sequence or recipe file. Pull requests from outside the project are not accepted. Report vulnerabilities privately through the security policy.

MIT © Marmik Shah