He said McAnulty accused him of mismanaging staff, of being a "terrible MP" and telling him that if his staff were not showing up to work, it was his job to pick up the slack.
McAnulty has denied all accusations of bullying Sharma.
Sharma told Newshub he wrote the letter as he was determined to create a paper trail – and the Labour Party was determined not to.
This follows from his claims MPs were coached on how to avoid Official Information Act requests – something the Prime Minister's office has refuted.
In a statement to the NZ Herald, the PM's office said it "both understands and acts in accordance with the OIA."
"The Government ... will continue to support MPs to understand their obligations under the Act," the statement said.
Sharma said the lack of an independent investigation into his unfounded claims of bullying is proof the Labour Party has something to hide, and all he wants is an inquiry.
"The end game is to get justice – I've been bullied for a long time; I want justice but the Prime Minister's office doesn't want to resolve it. They don't want to investigate someone."
A statement from the Prime Minister's office provided to the Herald said it was known from the start Sharma met with and wrote to the chief of staff.
"The allegations in this have been aired and refuted. They also misrepresent the meeting."
The statement said following the letter, an email agreement was reached, Sharma could begin recruiting for roles in electoral office staff, and choose a mentor.
"It was also agreed this represented moving on from the issues discussed and putting them behind us.
"Regardless the caucus will meet on Tuesday to discuss expelling Gaurav as a result of his continued breaches of trust."
