The notes from the former chief of staff to White House counsel Don McGahn revealed a chaotic and fearful White House during the special counsel investigation.

Those notes provided a guiding narrative and detailed account of unique moments with President Donald Trump.

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The notes from a single staffer working in President Donald Trump's White House became a crucial element of the final report from special counsel chief and former FBI Director Robert Mueller, lending his team a guiding hand about an administration constantly enveloped in chaos.

Annie Donaldson, a lawyer who served as chief of staff to former White House counsel Don McGahn, provided detailed accounts of everyday life in the Trump White House. When they became public with the partially redacted release of Mueller's report, it both enraged Trump and shed light on the inner workings of his administration.

Read more: Trump broke down and cursed upon learning of the special counsel's appointment: 'This is terrible. This is the end of my Presidency.'

"Statements are made about me by certain people in the Crazy Mueller Report, in itself written by 18 Angry Democrat Trump Haters, which are fabricated & totally untrue," Trump wrote on Twitter during one of his early morning tirades. "Watch out for people that take so-called 'notes,' when the notes never existed until needed."

But Donaldson's notes provided key insights, including details of how Trump could become seething with anger at a moment's notice.

Shortly after former FBI Director James Comey confirmed that the FBI was indeed looking into whether the Trump campaign could have colluded with the Russian government during the 2016 election, Donaldson wrote down descriptions of how angry Trump had become at the news.

"POTUS in panic/chaos," she wrote, using the shorthand for President of the United States. "Need binders to put in front of POTUS. All things related to Russia."

Donaldson also described the rampant fear that Trump could be charged with obstruction of justice — something Mueller left open ended in his report and Attorney General William Barr decided against pursuing.

"Is this the beginning of the end?" Donaldson wrote after the abrupt firing of then-FBI Director James Comey.

Donaldson also detailed colorful quotes from McGahn and jotted notes such as one from the March of 2017 which said, "Just in the middle of another Russia Fiasco."

Read more: Trump's inner circle celebrates the release of the Mueller report as a 'complete and total vindication' of the president

In all, the more than 60 notes from Donaldson revealed in the Mueller report, which otherwise would have never been available to the public, showed similar detail about intimate and tense situations inside a chaotic White House.

Notes and testimony from former Attorney General Jeff Sessions' chief of staff detailed embarrassing moments in the White House, like how Trump slouched into his chair and worried that his presidency was finished, as well as other details like how Sessions carried a letter of resignation with him at all times.

Donaldson departed the White House in December and now works at an Alabama law firm ran by former Republican Sen. Luther Strange.