cypress

Use when working with Cypress for E2E testing, component testing, visual testing, or real-time test runner. Also use when configuring Cypress Cloud, writing custom commands, or debugging test flakiness in Cypress.

Model	Source	Category
sonnet	core	Testing

Overview

Cypress 15.10.0 (February 2026) — JavaScript E2E and component testing framework. Runs directly in the browser. Real-time reloading, time-travel debugging, automatic waiting.

Full Reference

Cypress

Overview

Cypress 15.10.0 (February 2026) — JavaScript E2E and component testing framework. Runs directly in the browser. Real-time reloading, time-travel debugging, automatic waiting.

Quick Reference

Item	Value
Current Version	15.10.0 (February 2026)
Install	npm install -D cypress
Config	cypress.config.ts
Open Runner	npx cypress open
Run Headless	npx cypress run
Component Test	npx cypress run --component
Node.js	20, 22, 24+ (18 and 23 dropped in v15)
Bundled Chromium	136.0.7103.149

Reference Index

Load the relevant file for the task at hand:

Task	File
Install, config, env vars, version migration	reference/installation-and-config.md
describe/it/hooks, retries	reference/test-structure-and-hooks.md
Command chaining, selectors, .within(), retry-ability	reference/commands-and-selectors.md
.should(), .and(), expect callbacks	reference/assertions.md
cy.intercept(), stubs, fixtures, route matching	reference/network-interception.md
React/Vue/Angular component mount, cy.mount()	reference/component-testing.md
Cypress.Commands.add(), TypeScript types	reference/custom-commands.md
cy.fixture(), cy.task(), test data setup	reference/fixtures-and-test-data.md
cy.viewport(), selectFile(), downloads	reference/viewport-and-files.md
cy.session(), loginByApi(), cy.origin() OAuth	reference/authentication.md
Cypress Cloud pricing/parallelism, GitHub Actions, Docker	reference/cloud-and-ci.md
Time-travel, cy.pause(), cy.debug(), flaky test diagnosis	reference/debugging.md
Error messages and fixes	reference/errors.md

Common Mistakes

Mistake	Fix
Using async/await with Cypress commands	Commands are enqueued, not Promises. Chain with .then()
Storing command results in variables	Use .then() or .as() aliases
Using cy.wait(5000) for timing	Use cy.intercept() + cy.wait("@alias") instead
Returning values from .then()	.then() yields to next command — doesn’t return to outer scope
Using Cypress.env() in v15.10+	Deprecated; migrate to cy.env() / Cypress.expose() before v16
Not using data-cy attributes	Brittle selectors break on CSS/structure changes
Using cy.route()	Removed in Cypress 12. Use cy.intercept()
Registering cy.intercept() after the triggering action	Register BEFORE the action that fires the request