Filter Items

Overview

The Filter Items node takes a list and emits only the elements that satisfy a condition expression, discarding the rest. Use it to narrow down arrays — such as battle results, lens outputs, or API response items — before passing data to downstream nodes. The condition is evaluated per item using a JSONPath or template expression; items that evaluate to truthy are routed to the matched output, and those that do not are routed to unmatched. An empty input list passes through without error, producing empty outputs on both ports.

Configuration

Field	Type	Required	Description
condition	string	Yes	Expression evaluated against each item to determine inclusion. Supports JSONPath (e.g. $.score >= 0.8) and template syntax (e.g. {{item.status}} === 'passed'). Items where the expression is truthy go to matched; falsy items go to unmatched.
inputPath	string	No	JSONPath into the incoming payload that resolves to the array to filter (e.g. $.results). Defaults to the root value when omitted, which must itself be an array.
stopOnError	boolean	No	When true, a runtime evaluation error on any item halts the node and routes the error to the error output. When false (default), items that throw evaluation errors are treated as non-matching and sent to unmatched.
limit	number	No	Maximum number of matched items to emit. Once the limit is reached, evaluation stops and remaining items are discarded. Useful for capping downstream load. No limit is applied when omitted.

Inputs

Port	Type	Description
input	any[]	The payload containing the array to filter. If inputPath is set, the node extracts the target array from this object; otherwise the value itself must be an array.

Outputs

Port	Type	Description
matched	any[]	Array of items for which the condition evaluated to truthy, in original order. Empty array when no items match.
unmatched	any[]	Array of items for which the condition evaluated to falsy (or threw when stopOnError is false), in original order.
error	object	Emitted when stopOnError is true and an item causes a condition evaluation error. Contains message, item, and index fields identifying the failure.

Example

{
  "nodeType": "filter_items",
  "config": {
    "condition": "{{item.score}} >= 0.75",
    "inputPath": "$.battle_runs",
    "stopOnError": false,
    "limit": 50
  }
}