# type_annotate_public_apis

> Details about the type_annotate_public_apis diagnostic produced by the Dart analyzer.



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_Missing type annotation on a public API._

## Description

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

## Example

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:

```dart
[!f!](x, y) => '';
```

## Common fixes

Add type annotations to the API:

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

