no-duplicate-param-tags

Disallow duplicate @param tags for the same parameter name.

Targeted pattern scope

This rule checks TypeDoc comments on function-like declarations and methods.

What this rule reports

This rule reports when the same parameter name appears in multiple @param tags within one comment block.

Why this rule exists

Duplicate parameter docs create ambiguity in rendered docs and usually indicate stale or copy-pasted comments.

❌ Incorrect

/**
 * Add two numbers.
 * @param left Left value.
 * @param left Duplicate doc.
 * @param right Right value.
 * @returns Sum.
 */
export function add(left: number, right: number): number {
    return left + right;
}

✅ Correct

/**
 * Add two numbers.
 * @param left Left value.
 * @param right Right value.
 * @returns Sum.
 */
export function add(left: number, right: number): number {
    return left + right;
}

Behavior and migration notes

This rule reports duplicates but does not autofix because deciding which duplicate text to keep is semantic.

ESLint flat config example

import typedocPlugin from "eslint-plugin-typedoc";

export default [
    {
        plugins: { typedoc: typedocPlugin },
        rules: {
            "typedoc/no-duplicate-param-tags": "error",
        },
    },
];

When not to use it

Disable only if your docs style intentionally duplicates parameter entries (rare and usually undesirable).

Package documentation

TypeDoc package documentation:

• TypeDoc @param tag

Further reading

Rule catalog ID: R015

• TypeDoc comments and tags

Adoption resources

• Pair with no-extra-param-tags and require-param-tags for full parameter-doc hygiene.