Here is the full list of all 29 Jawbreaker achievements.
Try to pet the feral dog in the alleyway
Find the Unique item “GPS Navigator”
Find the Unique item “Portable Radar”
Find the Unique item “Boston Betty’s Lighter”
Find the Unique item “Sawn-Off Shotgun”
Find the Unique item “Silenced Handgun”
Find the Unique item “Baby Face’s Gas Mask”
Find the Unique item “Crude Rifle”
Kill Bob’s Big Boy in “The Arena”
Kill Dark Tooth in “Darktooth’s Lair”
Kill Faceless Speaker in “Faceless Speaker”
Found the collectable Freaky Friend in “The Jump”
Found the collectable Freaky Friend in “Blackout”
Found the collectable Freaky Friend in “The Hide”
Found the collectable Freaky Friend in “Spider’s Web”
Found the collectable Freaky Friend in “Crash Pad”
Found the collectable Freaky Friend in “Toxicity”
Found the collectable Freaky Friend in "The Pit"
Found the collectable Freaky Friend in "Bridges"
Kill Enforcer X03 in "The Beast"
Pull the fire alarm in the Safe House
Get the main ending of Jawbreaker
Kill the guard dog in "The Core"
Find the Unique item “Combat Shotgun”
Get the main ending "The Insider" in Jawbreaker
Find the hidden Unknown item “Decrypter A”
Find the hidden Unknown item “Decrypter B”
Find the hidden Unknown item “Decrypter C”
Learn the truth about the collapse and the origin of the 'Jawbreaker' weapon