UI Schema

Scoped Arguments

Values injected by an enclosing construct, read through the $arg expression.

Scoped arguments are $-prefixed identifiers that name a value injected by an enclosing construct. They are read through the $arg expression:

{ "$arg": "$item" }
{ "$arg": "$0" }

Required

  • $arg (string): The scoped argument name (e.g. "$item", "$index", "$content", "$0", "$1").

Returns: The value of the referenced argument.

Available Arguments

Each construct injects its own arguments, valid only within its scope:

ArgumentInjected byValue
$itemMapsThe current array item
$indexMapsThe current item's index (0-based)
$contentTranslation tagsThe tag's formatted chunks
$0, $1ActionsThe callback's positional args

A document MUST NOT reference a scoped argument outside the scope of the construct that injects it.

Accessing Nested Values

Append a JSON Pointer path to the identifier to reach into a nested property or array element:

{ "$arg": "$0/email" }
{ "$arg": "$0/1" }
{ "$arg": "$item/name" }

Here $0/email reads the email property of the first positional argument, $0/1 reads the second element of an array argument, and $item/name reads the name property of the current map item.

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