Renders OpenUI programs in Phoenix LiveView.

<OpenUI.LiveView.renderer
  id={"msg-#{message.id}"}
  response={message.openui}
  components={MyAppWeb.AssistantUI}
  tool_provider={&MyApp.Tools.run/2}
  streaming={@streaming?}
>
  <:unknown :let={error}><p>{error.message}</p></:unknown>
</OpenUI.LiveView.renderer>

response is the program, or a stored message with ]]>openui: marker lines (OpenUI.Message). While streaming is true, pass the text accumulated so far; the renderer reads only what is new. Queries run when streaming turns false, or, with queries={:on_statement}, as soon as the statement holding each one and every statement it reads are complete: for a tool_provider that answers from results the host already holds.

components is a module that uses OpenUI.LiveView.Components. Each of its function components receives:

• every prop of the catalog under its catalog name: plain values; a prop that takes components arrives as rendered HTML (or a list of it), rendered with {@children}; an action prop arrives as attributes for a button (<button {@action || []}>), or nil without an action; a bound prop arrives with its current value;
• @bind, for components declared as fields: id, name and value attributes for the input (<input {@bind} />);
• @error, the validation rule a field failed at the last submit ("required", "email", ...) or nil;
• @loading, true while a query of the program is loading;
• @host, the host map given to the renderer, for what the host knows and the program does not (a currency, the status of a record). A new map re-renders the program.

tool_provider answers Query and Mutation: a map of tool names to fn args -> {:ok, data} | {:error, reason} end, or a function (name, args) -> {:ok, data} | {:error, reason} that returns {:error, {:tool_not_found, names}} for a tool it does not know.

The LiveView that renders the program receives:

• {:openui, id, %OpenUI.Event{}} for @ToAssistant, @OpenUrl and actions of the library;
• {:openui, id, {:state, state}} when the person changes state; store it with OpenUI.Message.build(content: program, context: [state]) and the renderer restores it when the message is shown again;
• {:openui, id, {:errors, errors}} when the error list changes, [] once it recovers.

Nothing a program contains can crash the page: a component that raises is left out and reported, an unknown component renders the :unknown slot (or nothing), and a failure of the renderer itself leaves the program empty and logs it. A catalog component cannot render a LiveComponent.