---
url: /rules/require-props-default-doc.md
---

# require-props-default-doc

This rule requires a documentation comment including a `@default` JSDoc tag for optional properties defined in a Construct's Props interface, to indicate their default behavior.\
The names of such Props interfaces typically follow a format like `XxxxProps` (e.g., `MyConstructProps`, `MyStackProps`).

Note: This rule does not apply to regular class properties or properties within general interfaces not intended as Construct Props.

***

#### 🔧 How to use

::: code-group

```ts [Oxlint]
// oxlint.config.ts
export default defineConfig({
  // ... some configs
  rules: {
    "awscdk/require-props-default-doc": "error",
  },
});
```

```js [ESLint]
// eslint.config.mjs
export default defineConfig({
  // ... some configs
  rules: {
    "awscdk/require-props-default-doc": "error",
  },
});
```

:::

#### ✅ Correct Example

```ts
import { IBucket } from "aws-cdk-lib/aws-s3";

interface MyConstructProps {
  // ✅ JSDoc comment including a `@default` tag for the optional property.
  /**
   * @default - No S3 bucket is associated.
   */
  readonly bucket?: IBucket;
}

// ✅ This rule does not apply to general interfaces that are not Construct Props.
interface Config {
  readonly bucket?: IBucket;
}
```

#### ❌ Incorrect Example

```ts
import { IBucket } from "aws-cdk-lib/aws-s3";

interface MyConstructProps {
  // ❌ No JSDoc comment for the optional property.
  readonly bucket?: IBucket;
}
```

```ts
import { IBucket } from "aws-cdk-lib/aws-s3";

interface MyConstructProps {
  // ❌ JSDoc comment exists, but the `@default` tag is missing.
  /** Some description without default value. */
  readonly bucket?: IBucket;
}
```