AguiA2ui
The names the A2UI-over-AG-UI convention is made of.
None of these is in the AG-UI specification. They are what upstream's @ag-ui/a2ui-middleware and ag-ui-a2ui-toolkit agreed on, read off their sources rather than a document, and a client that wants to be drawn to by those agents has to agree to the same strings. Kept in one place so that the day upstream renames one, the rename here is one line.
Properties
The activityType an ACTIVITY_SNAPSHOT carrying an A2UI surface is stamped with.
The forwardedProps key an agent's adapter reads to decide whether to inject its generate_a2ui tool this run. true, or a string naming a custom render tool; false turns injection off even where the server opted in, and absence defers to the server's own configuration. The adapters are explicit that this mirrors the LangGraph contract.
The key under which a tool result, or an activity's content, carries an array of A2UI envelopes: {"a2ui_operations": [{"version": "v0.9", "createSurface": {...}}, ...]}.
The name of the tool an agent calls to draw a surface. Its arguments are surfaceId, components and an optional data -- no version and, by design, no catalogId: the catalog is the host's to choose, so a model cannot name one the client never registered.
The description of the Context entry a client sends to say which catalog it draws.
The catalog upstream names when nothing else chose one. Not the id the v0.9 specification gives its basic catalog (.../v0_9/catalogs/basic/catalog.json); the toolkit's constant is this string, and it is the one on the wire.
The version upstream's toolkit and middleware put on every envelope they emit.
The v0.9 specification's own id for its basic catalog.
The v1.0 basic catalog's id -- the one a2ui-compose's BasicCatalog registers under.
Functions
The description of the Context entry that carries the render tool's usage guide, for the tool named toolName. The middleware sends it beside the schema entry when it injects the tool, and replaces an existing entry of the same description rather than adding one.