It’s a best practice not to type passwords into a shell prompt, as it will be logged in the shell history. Here’s an alternative.
read -s API_KEY && export API_KEY
read command will prompt for a variable and it is not echoed as it is typed. The
export command makes it available to other processes.
There are sometimes better options (e.g., writing
export statements to a file that is read via
source), but the above is a handy way of handling secrecy in a one-off way.