Chisel

Shift + A adds Chisel shapes. With the Chisel tool active it opens Chisel’s own Add Chisel Primitive menu; with any other tool, Blender’s Add menu carries the same shapes under Chisel, and two more actions under Chisel Actions.

A new shape appears at the 3D cursor, selected and active. Its size and turn can be changed right after, in the redo panel.

Add Chisel Primitive (Chisel tool)

the Add Chisel Primitive menu, a Blender curve selected: From Curve is available

EntryMakes
CubeA Box
OblongAn Oblong
NgonAn Ngon, a square of four points to start
TrapezoidA Trapezoid
PrismA Prism
SphereA Sphere
CylinderA Cylinder
ConeA Cone
CapsuleA Capsule
TorusA Torus
OutlineAn Outline: a closed outline of points, extruded
TubeA Tube through points
RailA Rail: a section swept along points
LatheA Lathe: a profile of points turned round an axis
From CurveA Tube, an Outline or a Lathe from each selected Blender curve, point for point. Greyed out until a plain Blender curve is selected. See From Curve
TextA Text shape. With a plain Blender text object selected, it turns that object into a Chisel Text instead of making a new one

Blender’s Add menu ▸ Chisel

Blender's Add menu with the Chisel submenu open

With any other tool active, Shift + A opens Blender’s Add menu. Its Chisel submenu holds the same entries as Add Chisel Primitive.

Blender’s Add menu ▸ Chisel Actions

Blender's Add menu with the Chisel Actions submenu open

EntryWhat it does
Convert to MeshTurns the selected Chisel shapes into a polygon mesh, see Convert to Mesh
Bake MapsBakes texture maps of the active shape, see Baking

The redo panel

Right after an add, the redo panel (bottom left of the 3D View, or F9) holds the new shape’s starting size and its turn. Changing a value rebuilds the shape in place.

the redo panel of a Cylinder

EntrySettings (default)
CubeSize (2 m)
OblongSize (2 m)
NgonSize (2 m): the side of the starting square
TrapezoidSize (2 m), Cap (0.5, 0 – 1): the top’s size against the base
PrismSize (2 m), Sides (3, 3 – 8), Angle (60°, 5° – 175°, three sides only): the apex angle
SphereRadius (1 m)
CylinderRadius (1 m), Depth (2 m)
ConeRadius 1 (1 m, the base), Radius 2 (0 m, the top), Depth (2 m)
CapsuleRadius (1 m), Depth (2 m, the straight part)
TorusMajor Radius (0.7 m), Minor Radius (0.3 m)
OutlineDepth (1 m)
TubeTube Radius (0.2 m)
RailRadius (0.2 m)
LatheAngle (360°, 0° – 360°): how far the profile turns
TextText (Text): the words, Depth (0.2 m)

Every entry also has Align, the new shape’s turn:

AlignThe new shape lines up with
World (default)The world axes
ViewThe 3D View, facing you
3D CursorThe 3D cursor’s rotation

Sizes have no upper limit; the minimum is 0.001 m (Radius 2 and a Capsule’s Depth can be 0).