An envelope that carries a letter. Children are ordinary atoms shown on the letter card. With mode open, the flap flips up and the letter rises out as p goes 0 to 1; with mode seal, the letter drops in, the flap closes and the stamp lands. Optional address line (to) and stamp text. Plain HTML and CSS, no script; standalone it renders the finished state (open: letter out; seal: sealed and stamped). Use inside a motion_timeline to show a message being packed or delivered, e.g. an A2UI payload wrapped as an MCP tool result.
| Surface | Note |
|---|---|
| Prints the final state (type fully revealed, numbers at their values, shapes drawn); no motion | |
| google-chat | Inline CSS functions and custom properties are not supported |
| Field | Type | Required |
|---|---|---|
| mode | "open" | "seal" (optional, default "open") | optional |
| width | integer. Envelope width px, 80-900; height is 5/8 of it. Default 360. | optional |
| blocks | array (max 3) of atom blocks shown on the letter. They render finished (they do not follow the envelope's p). | required |
| to | string (optional, max 60). Address line on the front, e.g. "ui://jobs/board". | optional |
| stamp | string (optional, max 24). Stamp text, e.g. "tool result". In seal mode it lands at the end. | optional |
| label | string (optional, max 40). Accessible name. Default "Envelope". | optional |
| fill | "#rrggbb". Envelope colour. Default a tint of the stage background. | optional |
| accent | "#rrggbb". Fold edges and stamp. Default the stage accent. | optional |
| color | "#rrggbb". Address text. Default the stage ink. | optional |
{
"type": "motion_envelope",
"blocks": [
{
"type": "body",
"text": "Example content."
}
]
}{
"identifier": "urn:air:a2uicatalog.ai:atom:motion_envelope",
"displayName": "Motion Envelope",
"type": "application/vnd.a2ui.atom+json",
"url": "https://a2uicatalog.ai/atoms/motion_envelope",
"capabilities": [
"web",
"google-meet-stage",
"google-apps-script-web",
"mcp-apps",
"android"
],
"description": "An envelope that carries a letter. Children are ordinary atoms shown on the letter card. With mode open, the flap flips up and the letter rises out as p goes 0 to 1; with mode seal, the letter drops in, the flap closes and the stamp lands. Optional address line (to) and stamp text. Plain HTML and CSS, no script; standalone it renders the finished state (open: letter out; seal: sealed and stamped). Use inside a motion_timeline to show a message being packed or delivered, e.g. an A2UI payload wrapped as an MCP tool result.",
"representativeQueries": [
"show a envelope that opens to reveal (or seals in) a letter of atoms, with address and stamp",
"an envelope that carries a letter. children are ordinary atoms shown on the letter card. with mode o",
"render a motion envelope"
]
}The renderer is an open-source Google Apps Script web app. Deploy your own instance in 4 commands — you own the URL, no dependency on the demo endpoint.
git clone https://github.com/a2uicatalog/a2ui
cd a2ui/apps-script-surface/gas-wired-renderer
clasp push && clasp deploy