The White House guest list will read like a Who's Who of American poetry on Jan. 3, beginning with A. R. Ammons and John Ashbery and marching resolutely through the alphabet to James Wright.

Exactly what will be done at the reception between 4 and 6 p.m. next Thursday is still uncertain and a White House staff meeting will work out the details toady. But the place will be wall-to-wall poets (about 75 of them, representing some 20,000 living, published poets in the United States) with a liberal mixture of editors and patrons of the art bringing the total to about 500.

The event, described as "a celebration of poetry and American poets," is being welcomed by some who feel that the White House has been a showcase for the performing arts during the Carter administration, but has focused relatively little attention on poetry.

"When you say it's in honor of poetry, don't capitalize the 'p,'" said an editor at Poetry magazine in Chicago. Representatives of the magazine originally suggested the idea to Sen. Charles Percy and Rep. John Brademas, who mentioned it to the White House.

Magazine spokesmen have also helped to select the guest list and send out invitations. "We don't want to give the impression that we think this is being done just for us," the editor said.

Writers who have been published in the magazine are prominent on the list, which includes such poets as James Dickey, Marilyn Hacker, John Hollander, Richard Hugo, Philip Levine, Maxine Kumin, Howard Nemerov and W. D. Snodgrass, as well as two poets named Shapiro, Harvey and Karl. a

Exactly who will attend is not yet certain -- an invitation has been sent, for example, to Odysseus Elytis, the Greek poet who won this year's Nobel Prize, but he has not yet said whether he will be there. One invitee who has regretfully declined is Archibald MacLeish, who will be in Florida. Robert Penn Warren will be away from home probably unable to attend; and William Meredith, poetry consultant to the Library of Congress, will be out of the country.

Malcolm Cowley, declining the invitation, gave as his excuse that "I live too far from the railroad tracks, and I am 81 years old."