{
  "name": "get-first-value",
  "description": "Returns the first non-null value produced by candidate child nodes",
  "signature": {
    "children": {
      "*": {
        "type": "lambda",
        "description": "Candidate value source evaluated until the first non-null value is produced",
        "required": true,
        "mode": "ExecutableLambda",
        "cardinality": "OneOrMore",
        "role": "Operand",
        "evaluation": "EvalSelf",
        "projection": "Value"
      }
    },
    "output": {
      "mode": "Value",
      "description": "Resolves to the first non-null value produced by the candidate child nodes"
    }
  }
}