A tool support is disclosed including-a fixed part, a moving part that is movable relative to the fixed part, a first crossmember linked to the moving part and a second crossmember. A tool includes a tool axis linked to the first and second crossmembers by pivoting links including articulation axes. A pointer is provided with a pointer axis parallel to the tool axis, the pointer being linked to the first and second crossmembers by pivoting links including articulation axes, with the articulation axes being parallel to one another. The tool support includes an immobilizer of occupy a first immobilized state in which it prevents a rotational movement on at least one articulation axis and a second released state in which it allows rotational movement on the articulation axes.