Build a component & variants

Build a frame or group for the reusable element and inspect its exact ID with batch_get.
Promote it with {"op":"create_component","id":"<frame-id>"} in batch_design. The master stays on canvas, and the response includes its component ID.
For states such as Default and Hover, name each standalone master with axis values such as Variant=Primary, State=Default and Variant=Primary, State=Hover, promote them, and pass their master node IDs to combine_variants. The result returns component_set and frame; the frame displays the variants as a grid. Plain master names instead form one Variant axis. Use get_design_system to read the exact set and axis values.
To expand a set later, promote another Axis=Value master and call add_variants with the set ID and its master node ID. remove_variant takes a member out as a standalone component, arrange_variants tidies the set frame, and rename_component changes a component or set name safely.
Expose a variant axis or a text, boolean, number, color, or instance-swap property with create_component_property. For a descendant field, bind it with bind_component_property using the descendant node ID and a compatible target such as {"prop":"text_content"}.
Place a linked copy with create_instance, passing the component or set ID and world x/y coordinates. Use set_instance_property with an exposed property ID or unique name and a value of the right type.
Change the master, screenshot an instance, and inspect its source under components/<set>/<variant>/master.fnx.

{"label":"Place button","ops":[{"op":"create_instance","component":"<component-or-set-id>","x":480,"y":120}]}

Master, variant-set, and exposed instance-property operations are in the external MCP schema. Read get_design_system after structural changes; invalid values fail and roll back the batch. Use rename_component rather than editing component metadata or folder names by hand.

In the editor, Go to main component on a variant-set instance opens the member the instance currently displays, including a member selected through a variable mode. Reset all overrides restores the resolved default member and its size. Save or discard a Code workspace draft before navigating to another component. A directly bound text-content variable controls its instance text; edit the variable or remove that binding before editing the text in place. Text reached through an exposed component-property alias remains editable.

The editor's Copy/Paste can carry a complete component or variant set with its captured definitions. If the original has been removed, Paste restores an independent usable copy. Cutting only part of a variant set is refused; select the whole set when it needs to move together. Review the saved FNX diff after structural changes.