JSDoc for a Simple Function

Documenting a Simple Function with JSDoc

The most common use of JSDoc is documenting a plain function with parameters and a return value. A well-documented function tells other developers (and your future self) what it does, what it expects, and what it returns.

Example Signature

function calculateArea(width: number, height: number): number

Generated JSDoc

/**
 * Calculates the area of a rectangle.
 *
 * @param {number} width - The width of the rectangle in pixels.
 * @param {number} height - The height of the rectangle in pixels.
 * @returns {number} The calculated area (width * height).
 */

Key Tags

Tag	Purpose
@param	Documents a function parameter with its type and description
@returns	Describes the return value and its type

Best Practices

• Start the description with a verb in third person ("Calculates", "Returns", "Validates")
• Include units or constraints in parameter descriptions when applicable
• Mention edge cases in the description (e.g., "Returns 0 if either dimension is negative")
• Keep the first line concise — use additional lines for details

JSDoc vs TSDoc

In JSDoc style, types are included in braces: @param {number} width. In TSDoc style, types are omitted because TypeScript already provides them: @param width. The generator handles both with a single toggle.