alerts

Reports uses of the global alert/confirm/prompt dialog APIs.

✅ This rule is included in the browser logical preset.

The legacy browser dialog APIs alert, confirm, and prompt are synchronous, blocking, and provide a poor user experience in modern web applications. They should be avoided in production code in favor of non-blocking UI patterns (for example, custom modals) or other mechanisms for collecting user input or showing messages.

Examples

❌ Incorrect

alert("Hello, world!");

if (!confirm("Are you sure?")) {
  return;
}

const name = prompt("What's your name?");

✅ Correct

console.log("Hello, world!");

if (!(await myCustomModal("Are you sure?"))) {
  return;
}

const name = await myCustomInput("What's your name?");

Options

This rule is not configurable.

When Not To Use It

If you’re writing quick temporary debugging snippets that never ship to users, or an internal-only page where the user experience does not matter, you might accept using alert/confirm/prompt locally. For production code and libraries, prefer non-blocking alternatives.

Further Reading

• MDN: window.alert()
• MDN: window.confirm()
• MDN: window.prompt()

Equivalents in Other Linters

• Biome: noAlert
• ESLint: no-alert
• Oxlint: eslint/no-alert