Cowart Open Canvas

Workflow

1. Use the Cowart MCP render_cowart_canvas_widget tool to open the canvas as a native Codex widget. Pass the user's active Codex workspace as projectDir; do not pass the Cowart plugin repository directory.

{
  "projectDir": "/absolute/path/to/user/codex-project"
}

The tool returns openai/outputTemplate: ui://widget/cowart/canvas.html, which tells Codex to render the widget directly. Do not start scripts/start-canvas.sh or open a localhost URL for normal use.

1. Confirm the widget opens for the user. The canvas data is stored in the active project:

canvas/pages/<page-id>/cowart-canvas.json
canvas/pages/<page-id>/assets/

1. If the MCP tool is not visible in the current session, use tool discovery for Cowart widget/render capabilities. If the plugin was just installed or upgraded, tell the user a new Codex conversation may be required for the new MCP tool schema to load.

Constraints

Do not launch the old local web service, inspect canvas files, run builds, check storage layout, take screenshots, or perform other validation steps unless opening the widget fails or the user explicitly asks for those checks. The scripts/start-canvas.sh path is now only a local-development fallback.