---
url: >-
  https://adk.nht.io/api/@nhtio/adk/batteries/orchestration/type-aliases/PredicateOp.md
description: The closed set of comparison operators a structured predicate leaf may name.
---

# Type Alias: PredicateOp

```ts
type PredicateOp =
  | "eq"
  | "ne"
  | "lt"
  | "lte"
  | "gt"
  | "gte"
  | "in"
  | "contains"
  | "truthy"
  | "exists";
```

Defined in: [src/batteries/orchestration/predicates.ts:13](https://github.com/NHTIO/ADK/blob/v1.20260906.0/src/src/batteries/orchestration/predicates.ts#L13)

The closed set of comparison operators a structured predicate leaf may name.

`truthy` and `exists` take no `value`; every other operator requires one. The set is CLOSED —
`parseStructuredPredicate` refuses any other string with a model-addressed reason naming the
legal set, so a branch/select author cannot smuggle an operator no cell implements.