This story has been updated.

MUSCATINE, Iowa - In case her Republican rivals forgot what Hillary Rodham Clinton did in four years as secretary of state, the Democratic presidential candidate sent along a little primer recently, she told an audience here on Tuesday.

Well, not that little. Clinton's 2014 memoir "Hard Choices" is firmly in the what-I-did-in-Washington doorstop genre. But it does include a chapter-by-chapter account of Clinton's work on hot button issues including Iran, North Korea and Egypt.

Clinton said Republicans bashing her time as America's top diplomat seem to have overlooked a few things, so she and some aides decided to send copies of the book to each candidate. A campaign aide said a copy was sent last week to each candidate who participated in the latest GOP debate on Sept. 17.

"I understand that you and your fellow Republican candidates for president were questioning my record of accomplishments at your last debate, so I thought you might enjoy reading my book, Hard Choices," Clinton wrote in an accompanying letter.

"From working to restore America’s standing in the world to bringing crippling sanctions to Iran to negotiating a ceasefire in Gaza, please enjoy all 596 pages of my time as secretary of state. With 15 candidates in the race, you’ve got enough people for a book club!"

GOP candidates have criticized Clinton as a secretary of state without significant accomplishments, such as a major peace treaty. Carly Fiorina regularly scoffs at Clinton's record-setting globetrotting, saying "flying is an activity, not an accomplishment."

Some Republican presidential hopefuls responded to news of the gift by offering their own:

The campaign of Republican Jeb Bush wouldn't say whether he'd received his copy of the Clinton memoir. But Bush spokeswoman Kristy Campbell said that the candidate "hopes Secretary Clinton will have an opportunity to read his e-book, 'Reply All,' when it comes out in a few weeks. The book, based on Governor Bush's emails while in office, is a good lesson on the importance of transparency in government."

Ed O'Keefe contributed to this story.