type_annotate_public_apis

Missing type annotation on a public API.

The analyzer produces this diagnostic when the declaration of part of the public API of a package doesn't have explicit type annotations.

The following code produces this diagnostic because the function f doesn't have an explicit return type and the parameters x and y don't have explicit types:

f(x, y) => '';

Add type annotations to the API:

String f(int x, int y) => '';

Unless stated otherwise, the documentation on this site reflects Dart 3.8.0. Page last updated on 2025-05-08. View source or report an issue.