How do I tell sleeve from sleeve shunt on this connector?

The sleeve shunt will disconnect from the sleeve when you insert a connector. At the bottom of the drawing they make contact. When you insert a connector that will connect to the lower contact. If you follow that to the right and up you see that it has its soldering tab at the top.

Typical use of the sleeve shunt is to connect it via a pull-up connector to V+. If the plug isn't inserted the voltage level at the sleeve shunt will be ground, with the plug inserted it will be V+.

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You can also test it by inserting a connector carrying a voltage. You'll measure the voltage between the central pin and the sleeve tab, but nothing between center pin and sleeve shunt.

What is written above is confusing dialog. "The hook is the contact for your connector's sleeve." This is the last statement from stevenvh. This is correct.

But, stevenvh also says "When you follow the shunt (the longer bit with the hook, the hook will make the contact with the connector's sleeve) to the right it bends to follow the housing, and at the top it reappears at exactly the same horizontal position. The shunt is NOT the longer bit with the hook!

In the drawing shown the sleeve contact is at the top. The sleeve is the receptacle connector part with the hook with the sleeve of an inserted power cable end connector making contact at the hook. The connector part with the hook then continues to the right and bends up to follow the connector housing.

The shunt contact is shown at the front of the drawing, with the center pin contact is shown at the back.

The shunt breaks connection with the sleeve when a mating connector is inserted. This happens because the sleeve on the inserted cable end connector contacts and compresses the hook, pushing it away from and disconnecting it from the small shunt part inside the receptacle connector.