You Do Need power plug adapter while traveling from Tokelau to Saint Lucia.

Here is Why You Need An Adapter

The outlet and plug type used in Saint Lucia is G and in Tokelau is I. This is how they look like.

Tokelau

In Tokelau, outlets of type I are in use.

Type I

Saint Lucia

In Saint Lucia, outlets of type G are in use.

Type G