throwErrors

Reports throwing values that are not Error objects.

✅ This rule is included in the ts logical presets.

Only Error objects (or objects that extend Error) should be thrown. Throwing non-Error values has several downsides:

• No stack trace information for debugging
• Inconsistent error handling behavior
• Cannot use standard error properties like cause, message, or name

This rule reports on any throw statement where the value being thrown is not an Error.

Examples

❌ Incorrect

throw "Something went wrong";

throw { message: "error", code: 500 };

✅ Correct

throw new Error("Something went wrong");

class HttpError extends Error {
  constructor(
    message: string,
    public code: number,
  ) {
    super(message);
    this.name = "HttpError";
  }
}
throw new HttpError("error", 500);

Options

This rule is not configurable.

When Not To Use It

If you’re working with legacy code that throws non-Error values and refactoring would be too costly, you may disable this rule.

Further Reading

• MDN: Error
• MDN: throw

Equivalents in Other Linters

• Biome: useThrowOnlyError
• Deno: no-throw-literal
• ESLint: no-throw-literal@typescript-eslint/only-throw-errorunicorn/throw-new-error
• Oxlint: eslint/no-throw-literaltypescript/only-throw-errorunicorn/throw-new-error