Harlowe's link syntax is slightly different to other formats - inside matching non-nesting pairs of [[ and ]], place the link text and the passage name, separated by either -> or <-, with the arrow pointing to the passage name.

You can also write a shorthand form, where there is no <- or -> separator. The entire content is treated as a passage name, and its evaluation is treated as the link text.

Example usage:

[[Go to the cellar->Cellar]] is a link that goes to a passage named "Cellar".
[[Parachuting<-Jump]] is a link that goes to a passage named "Parachuting".
[[Down the hatch]] is a link that goes to a passage named "Down the hatch".

Details:

The interior of a link (the text between [[ and ]]) may contain any character except ]. If additional ->s or <-s appear, the rightmost right arrow or leftmost left arrow is regarded as the canonical separator.

[[A->B->C->D->E]] has a link text of
A->B->C->D
and a passage name of
E

[[A<-B<-C<-D<-E]] has a link text of
B<-C<-D<-E
and a passage name of
A

This syntax is not the only way to create links – there are many link macros, such as (link:), which can be used to make more versatile hyperlinks in your story.