Read the ordered call trace of a canvas — genui

The trace is the spec of record for a canvas: every validated call the model made (create, update, remove, clear), in order, as plain JSON-friendly lists. genui_replay() can rebuild the canvas from it with no LLM configured. Embedded input state is intentionally ephemeral and never recorded.

Usage

genui_trace(session = shiny::getDefaultReactiveDomain(), id = NULL)

Arguments

session: The Shiny session (defaults to the current reactive domain).
id: The genui_server() module id to read, relative to session. May be omitted when the session has exactly one canvas.

Value

A reactive expression returning the trace: a list of entries of the form list(op = "create", id = "c1", component = "...", args = list(...)) (plus parent_id for children; update entries carry the validated argument delta). Persist it with saveRDS() to replay in a later session.

Examples

note <- genui_component(
  name = "note_card",
  description = "A card showing a short note.",
  args = list(text = "The note text."),
  ui = function(id, args) htmltools::p(args$text)
)
catalog <- genui_catalog(note)
chat <- ellmer::chat_openai(
  model = "gpt-5.6-sol",
  credentials = function() list(api_key = "not-used")
)
shiny::testServer(
  genui_server,
  args = list(id = "canvas", catalog = catalog, chat = chat),
  {
    trace <- genui_trace(session)
    stopifnot(identical(trace(), list()))
  }
)