The seiton playground is a static page: after the WASM runtime loads, it parses and lints GitHub Actions workflow and action metadata YAML in your browser. Your YAML is not uploaded to a server for analysis.
You can edit YAML in the editor, load built-in samples, open a document from a URL you enter (your browser requests that URL directly), or use Share to store workflow YAML and lint config in the page URL when it fits. If the URL would be too long, Share falls back to workflow YAML only or copies both to your clipboard. Very large snippets may exceed browser URL length limits when sharing.
There are practical limits to what the playground can do:
run: steps on
GitHub’s
infrastructure.
enable-network: true
is set in config, SHA/digest pinning resolves via the GitHub API (unauthenticated, 60 requests/hour limit).
The source code is available on GitHub.