Source forms
The forms below are header patterns: square brackets mean optional syntax, | lists alternatives, and words such as selector, value and caption are placeholders. They are source fragments requiring the stated owner, not complete applications. Content suites use ordinary indented Can; named slots use slot name with a nonempty indented suite. Slots cannot mix with regular direct children.
Appearance options are optional and limited to the per-entry values below. No raw classes, arbitrary properties or event handlers are accepted. Input captions derive from their fields. A selector has at most one writable control, and unmentioned eligible inputs still render in owning schema order. A collection/result scope ends field placement unless it contains a new explicit field owner.
alert
Header: alert [notice]. Expression-only leaf, or a nonempty readable-content suite. Business invocation and activation children are invalid.
Appearance: tone=info|success|warning|error, variant=solid|outline|soft, orientation=horizontal|vertical.
aura
Header: aura. Requires a nonempty scope-transparent content suite; it adds presentation only.
Appearance: size=xs|sm|md|lg|xl, variant=solid.
badge
Header: badge value. Leaf displaying a readable typed value.
Appearance: tone=neutral|primary|secondary|accent|info|success|warning|error, size=xs|sm|md|lg|xl, variant=solid|outline|soft|ghost, caption=text.
chat_bubble
Header: chat_bubble. Requires its named-slot suite; it performs no automatic business comparison, state transition or messaging.
Slots: slot content (required, once); slot avatar (optional, once); slot header (optional, once); slot footer (optional, once).
Appearance: tone=neutral|primary|secondary|accent|info|success|warning|error, variant=solid.
countdown
Header: countdown value. Leaf displaying a numeric or duration value; it does not schedule work.
Appearance: variant=solid, caption=text.
diff
Header: diff. Requires its named-slot suite; it performs no automatic business comparison, state transition or messaging.
Slots: slot before (required, once); slot after (required, once).
hover_3d
Header: hover_3d. Requires a nonempty content suite; interactive descendants are invalid.
indicator
Header: indicator. Requires its named-slot suite; it performs no automatic business comparison, state transition or messaging.
Slots: slot content (required, once); slot indicator (required, once).
kbd
Header: kbd text. Leaf displaying escaped shortcut notation; it registers no keyboard handler.
Appearance: size=xs|sm|md|lg|xl, variant=solid.
loading
Header: loading [state]. Leaf; omission is an authored placeholder. It does not infer provider state.
Appearance: size=xs|sm|md|lg|xl, variant=solid.
mask
Header: mask. Requires a nonempty scope-transparent content suite; it adds presentation only.
mockup_browser
Header: mockup_browser. Requires a nonempty scope-transparent content suite; it adds presentation only.
mockup_code
Header: mockup_code text. Leaf displaying escaped text; it executes no code.
mockup_phone
Header: mockup_phone. Requires a nonempty scope-transparent content suite; it adds presentation only.
mockup_window
Header: mockup_window. Requires a nonempty scope-transparent content suite; it adds presentation only.
progress
Header: progress value max=bound. Leaf with a required compatible numeric maximum.
Appearance: tone=neutral|primary|secondary|accent|info|success|warning|error, variant=solid, caption=text.
radial_progress
Header: radial_progress value max=bound. Leaf with a required compatible numeric maximum.
Appearance: variant=solid, caption=text.
skeleton
Header: skeleton [state]. Leaf; omission is an authored placeholder. It does not infer provider state.
stat
Headers: stat observations or the slotted form stat. A typed metric leaf, or a named-slot suite with required value slot. The slotted form has no positional value.
Slots: slot value (required, once); slot title (optional, once); slot description (optional, once); slot icon (optional, once).
Appearance: variant=solid, orientation=horizontal|vertical.
status
Header: status value. Leaf displaying explicit state with a text alternative.
Appearance: tone=neutral|primary|secondary|accent|info|success|warning|error, size=xs|sm|md|lg|xl, variant=solid, caption=text.
steps
Header: steps [sequence]. Requires item slots. With a query or typed readable sequence, exactly one slot item template renders for each admitted row; without an operand, repeated authored slot item suites are explicit items. Scope, field grants and stable ordering remain checked.
Slots: slot item (required, repeatable).
Appearance: variant=solid, orientation=horizontal|vertical.
A container tone= is rejected; step tones belong to the item presentation contract and are not arbitrary attributes on slot item.
swap
Header: swap [value]. Requires off/on slots. A supplied value is a readable bool or owned bool preference; omitted selection is transient view state.
Slots: slot off (required, once); slot on (required, once).
text_rotate
Header: text_rotate [sequence]. Requires item slots. With a query or typed readable sequence, exactly one slot item template renders for each admitted row; without an operand, repeated authored slot item suites are explicit items. Scope, field grants and stable ordering remain checked. At most six items; reduced-motion behavior applies.
Slots: slot item (required, repeatable).
timeline
Header: timeline [sequence]. Requires item slots. With a query or typed readable sequence, exactly one slot item template renders for each admitted row; without an operand, repeated authored slot item suites are explicit items. Scope, field grants and stable ordering remain checked.
Slots: slot item (required, repeatable).
Appearance: variant=solid, orientation=horizontal|vertical.
toast
Header: toast [notice]. Expression-only leaf, or a nonempty readable-content suite. Business invocation and activation children are invalid.