Internal emails obtained by ABC under the Freedom of Information act show officers were to do "status checks" of suspected illegal immigrants.
Operation Fortitude was cancelled in August after a public outcry and accusations of racial profiling.
The ABF at the time blamed a "clumsily worded" media release for the furore.
Senior officials have since apologised for the "public confusion, concern and distress" caused by the operation, which had been planned as part of a general crime crackdown involving several security agencies.
The emails obtained by ABC's 7:30 programme show that six ABF officers were to carry out checks at the taxi ranks on Flinders Street and Southern Cross Station.
The documents state that special "talking points" were also provided to the officers by the immigration authorities.
These instructed that when asked about who the operation was targeting, the officers should reply: "We will be speaking with any individual we cross paths with."
The initial public statement from the ABF in August said a "diverse team of transport and enforcement agencies" would be operating in Melbourne.
"You need to be aware of the conditions of your visa; if you commit visa fraud you should know it's only a matter of time before you're caught out."
The ABF later issued a "clarifying statement", saying: "[We] will not be 'stopping people at random' in Melbourne to 'check people's papers' as reported in media."
"The ABF does not and will not stop people at random in the streets and does not target on the basis of race, religion, or ethnicity."
But Operation Fortitude was aborted only hours after it was announced, as hundreds of people responded to a social media outcry by holding a protest rally near Flinders Street station.
Earlier this week, Immigration Secretary Mike Pezzullo told a Senate committee: "It is clear that the media release issued that morning was very badly worded and gave rise to the impression that the ABF has general powers of questioning people in the street."
"It does not, and I apologise for the impression that was wrongly created. We certainly don't rely on racial profiling at all."
The Australian Border Force (ABF) had planned random checks at Melbourne taxi ranks as part of an aborted visa fraud operation, local media report.