The frontman has voiced his concerns about the metal act topping the bill at Worthy Farm later this month and thinks the band are an ''interesting choice'' but isn't convinced their performance would sit well with festival goers' ''fragile'' state.
Speaking to BBC 5 Live, he said: ''They've probably not had much sleep and they've been indulging in certain things.
''So the main thing is to be a vague, warm, friendly presence. ''Whether a full-borne rendition of 'Enter Sandman' is going to fill those criteria I don't know.''
Pulp headlined the event in 1995 when The Stone Roses had to pull out and Jarvis will be back at the festival this year to take to the decks for a DJ set.
Metallica recently defended their upcoming Glastonbury performance, with drummer Lars Ulrich saying there's a point where the criticism directed at them ''becomes ridiculous.''
However, an online petition to ban the act from Glastonbury has been launched by animal rights activists and more than 30,000 followers have joined the page on Facebook.
The petition - entitled 'Remove Metallica from Glastonbury festival for their support of bear hunting' - already has more than 22,000 'likes' on the site.
Singer and guitarist James Hetfield, who is an avid hunter and member of America's National Rifle Association, is set to narrate an eight-part series called 'The Hunt' on the History Channel, which focuses on the killing of Kodiak brown bears in Alaska.
The petition was set up following the announcement and many regular festival-goers also feel the band's music isn't in keeping with Glastonbury, which is traditionally a 'hippy' event.