The A2UI React renderer (packages/a2ui-renderer/src/react-renderer/a2ui-react/A2uiSurface.tsx:152)
always begins rendering at the component with id="root":
export const A2uiSurface: React.FC<{...}> = ({ surface }) => {
// The root component always has ID 'root' and base path '/'
return <DeferredChild surface={surface} id="root" basePath="/" />;
};
If no component has that ID, DeferredChild falls through to its loading-
shimmer placeholder, so the surface silently renders as an empty ~30px
rectangle regardless of how many other components are on the surface.
The generation guidelines shipped to the sub-LLM (in @copilotkit/shared
and copilotkit sdk-python) never stated this requirement. Fixed-schema
demos hard-code a component with id="root" in their JSON and work; dynamic
demos relied on the LLM guessing, which it sometimes did and sometimes
didn't. The failure mode is particularly nasty: no error, no warning,
just a loading spinner that never resolves.
Adds the requirement to COMPONENT ID RULES in both the TS and Python
guideline strings. Both strings are injected into the sub-LLM's context
by A2UICatalogContext (packages/react-core) and
copilotkit.a2ui.a2ui_prompt() respectively, so every A2UI-enabled app
picks it up automatically — no per-demo change needed.
Stacked on #4216, which restores the same instruction to the
langgraph-python-threads demo's tool docstring (belt-and-braces until
consumers update their shared package version).
- Replace custom { name, props } schema format with spec-aligned inline
catalog format (allOf + properties) so the LLM sees the same flat
structure it must produce — eliminates "props" nesting confusion.
- Restructure generation prompts: inline literal values are the default,
path binding is a narrow schema-driven exception for form inputs.
- Export InlineCatalogSchema type from a2ui-renderer.
LLMs sometimes use path bindings (e.g. {"path": "/chartData"}) on
component properties that only accept literal values, causing silent
render failures. The new guideline tells the LLM to check the schema's
anyOf type before using path bindings.
Add copilotkit.a2ui module with operation builders and prompt helpers,
fix SystemMessage ID reuse in before_agent to prevent LangGraph duplication,
add Pydantic model_dump serialization for app_context.
Jordan Ritter