Position placeholder in validation messages

In Laravel 9 you can use the :position placeholder in validation messages if you're working with arrays.

This will output: "Please provide an amount for price #2"

 1class CreateProductRequest extends FormRequest
 2{
 3    public function rules(): array
 4    {
 5        return  [
 6            'title' => ['required', 'string'];
 7            'description' => ['nullable', 'sometimes', 'string'],
 8            'prices' => ['required', 'array'],
 9            'prices.*.amount' => ['required', 'numeric'],
10            'prices.*.expired_at' => ['required', 'date'],
11        ];
12    }
13 
14    public function messages(): array
15    {
16        'prices.*.amount.required' => 'Please provide an amount for price #:position'
17    }
18}

Tip given by @mmartin_joo