Officers were in the Soho Road area of Handsworth on Sunday where they spotted a vehicle they became suspicious of in Grove Lane.
Two men aged 18, and a 17-year-old boy were arrested.
Daquan Sterling, aged 18, was charged with possession of Class B drugs with intent to supply.
Elijah Marshall, aged 18, was charged with possession of an offensive weapon.
The 17-year-old boy was charged with possession of Class B drugs with intent to supply.
All three will appear before magistrates at a later date.
Operation Guardian is a specialist taskforce which places a particular emphasis on reducing knife crime in under 25-year-olds, through a range of tactics from plain-clothed operations to high visibility patrols.