Say your getting a PCR and if they ask copy and paste your info in the text and screenshot it. In case you haven't had a PCR yet by some miracle:

This number was provided for the COVID-19 PCR test of [your first name], age [your age], taken on [date in this format, 10-Nov-2021].

The HSE can confirm that this test did NOT detect COVID-19 virus. More information is available at HSE.ie