aws cli output automatically being sent to vi

I am learning the AWS CLI (v2) - a software command line tool to work with code, resources and other administration purposes in AWS - and have installed it on Ubuntu 18.04. I am running zsh with oh-my-zsh installed. I am trying to get aws command output to be reported back to the terminal as a JSON string (or even as text), but the output is always redirected to vi.

My AWS account is brand new - no EC2 instances. When I run the following command:

aws ec2 describe-instances

It sends the expected output value (e.g. { "Reservations": [] }), but directly to vi instead of outputting a JSON string to the terminal requiring closing vi afterwards. This occurs regardless of output format (json, text, table) or what shell I use (bash, zsh).

I am not sure if this is a AWS CLI configuration issue/change or a shell/Linux configuration issue/change

• I've reviewed my .zshrc, .bashrc, .bash_profile and .bash_aliases files and have not seen any obvious solution here that would change or redirect output.
• I've been scouring the AWS CLI documentation, Stack Overflow and Google and I have not found a fix or a similar case.

It was the PAGER environment variable set to "less" (which I was confusing with vi).

This fix is to update the ~/.aws/config file and setting cli_pager to an empty value, e.g. :

[default]
region = us-west-2
output = json
cli_pager =

Thank you to Sorin who commented on my question lead me to the answer.