{parms} stands at the top of a custom tag's template - a .pad file in _tags/ or _common - and declares which parameters the tag takes. It prints nothing.

• A name alone is required: a caller that leaves it out gets an error - the {card} needs the parameter title=.
• name=default is optional: what the caller left out is filled in with the default, and reads as {#name} exactly like a given parameter.

Once a tag declares its parameters, the strict check also reports a parameter that the caller gives but the tag does not declare - the tag {card} has no parameter 'titel' - it declares title, tone - so a typo at the call is caught instead of silently ignored. The items are read raw, as {attrs} reads them, so a default may be any expression.

A {parms} outside any custom tag's template is an error under the strict check. The examples use the application's tag _tags/parmsBadge.pad, which starts with {parms label, tone='info', count=0}.