As RP says, these sorts of tap fitting are available (some are saddle type with a pin that punctures the supply line and others are compression type that requires cutting into the pipe). I agree that both types are prone to leaks, especially if you are splicing into “old” copper lines. I never use these methods, even if they are code-anctioned and often seem to work, because I don’t want to be called back in the middle of the night because of a leak… I prefer to use soldered joints, or flare fittings, or well-connected compression ring fittings (in that order of preference).
NtP