---
id: api/cypress-api/iscy
title: Cypress.isCy | Cypress Documentation
description: >-
  Cypress.isCy checks if a variable is a valid instance of cy or a cy chainable
  in Cypress.
section: api
source_path: docs/api/cypress-api/iscy.mdx
version: 3cf5b86b3403f604bdf7f3e35025c3bc3865e02c
updated_at: '2026-05-07T17:44:31.931Z'
---
# Cypress.isCy

`Cypress.isCy()` checks if a variable is a valid instance of `cy` or a `cy` chainable.

This utility may be useful when writing a plugin using [Node Events](/llm/markdown/api/node-events/overview.md) for Cypress and you want to determine if a value is a valid Cypress chainable.

## Syntax

```
Cypress.isCy(obj)
```

### Arguments

**obj _(Object)_**

The object to test.

## Examples

```
Cypress.isCy(cy) // trueconst chainer = cy.wrap().then(() => {  Cypress.isCy(chainer) // true})Cypress.isCy(undefined) // falseCypress.isCy(() => {}) // false
```