tool
The create_teams_card Mastra tool: a model describes a card in the small
card.CardSpec vocabulary and gets back a compiled Adaptive Card
document. Unlike send_email, building a card is a pure, side-effect-free
transform - nothing leaves the building - so it is NOT approval-gated: the
card is data the app then decides what to do with (render it in a preview,
post it to a Teams incoming webhook, attach it to a bot reply).
The build runs through the executor the plugin installs on the shared runtime, so a build from this tool picks up the same telemetry / timeout chain as one from the AppKit tool. In a Mastra app with no AppKit plugin registered the build still runs, just without interceptors.