While she was Secretary of State, Hillary Clinton exchanged 18 emails with President Barack Obama from her private email account. But the State Department declined to release the emails when it was forced by a VICE News Freedom of Information Act (FOIA) lawsuit to disclose 30,000 of Clinton's communications over the course of a year.

"As the White House has previously stated, Secretary Clinton and the president did on occasion exchange emails," State Department spokesperson John Kirby explained at a press briefing last January. "As they have also said previously, such presidential records shall remain confidential to protect the president's ability to receive unvarnished advice and counsel, but will ultimately be released in accordance with the Presidential Records Act."

On Thursday, the State Department turned over an index to VICE News and the conservative watchdog group Judicial Watch describing the subject matter of the emails Clinton and Obama discussed via email — and it doesn't appear to rise to the level of "unvarnished advice."

According to the State Department, they were thank-you notes, words of encouragement, a "note of appreciation," a holiday message, a "personal pleasantry," and so on. A government summary of the emails' content is below.

All of the emails were exchanged between May 18, 2012 and January 31, 2013. Obama sent eight emails to Clinton. One of the exchanges listed in the index was an email that was forwarded to Clinton's aide Monica Hanley "of notes of congratulation and appreciation referenced in documents."

All of the emails were withheld under presidential privilege and privacy act and deliberative process exemptions to the FOIA.

The new details about Clinton's communications with Obama were formally made in a so-called Vaughn Index, a document prepared in FOIA lawsuits in which government agencies justify the withholding of information under a FOIA exemption.

Last month, the State Department turned over to VICE News a separate Vaughn Index related to the 22 top-secret emails Clinton exchanged with three aides through her private server. However, the State Department said the contents of the communications were so highly classified it could not even reveal the date the emails were sent and received, or the subject matter.

The FBI spent a year investigating Clinton's email practices. As VICE News first reported, the FBI's probe stemmed from a "Section 811" referral from the Intelligence Community's Inspector General (ICIG). The ICIG determined that classified, national security information in Clinton's emails may have been "compromised" and shared with "a foreign power or an agent of a foreign power."

After the FBI wrapped up its investigation last July, the bureau recommended to the Department of Justice that neither Clinton nor any of her aides should face charges. In an extraordinary news conference, FBI director James Comey said that while the FBI "did not find clear evidence that Secretary Clinton or her colleagues intended to violate laws governing the handling of the classified information, there is evidence that they were extremely careless in their handling of very sensitive, highly classified information."