The RAAF Mirages carried a canopy breaking tool. It was similar to a heavy duty dagger with a very short thick blade cut off at 45 degrees. On one occasion, when a canopy was due for replacement, an exercise was held to test the tool. It took considerable effort by the pilot to break the canopy. Then even more to make a large enough hole in order to escape.
(The aircraft also carried a tool on the coaming able to puncture the life raft within the ejection seat. In case it accidentally inflated in flight.)