Yes, the usual trace/0 and spy points abilities are available
http://www.gprolog.org/manual/html_node/gprolog013.html
Here is a simple example
$ gprolog
GNU Prolog 1.4.5 (32 bits)
Compiled Dec 3 2020, 00:37:14 with gcc
By Daniel Diaz
Copyright (C) 1999-2020 Daniel Diaz
| ?- [user].
compiling user for byte code...
something(A):- something_else(A).
something_else(A):- A is 2 + 2.
user compiled, 2 lines read - 414 bytes written, 19475 ms
(10 ms) yes
| ?- spy(something_else).
Spypoint placed on something_else/1
The debugger will first leap -- showing spypoints (debug)
(1 ms) yes
{debug}
| ?- something(X).
+ 2 2 Call: something_else(_23) ?
3 3 Call: _23 is 2+2 ?
3 3 Exit: 4 is 2+2 ?
+ 2 2 Exit: something_else(4) ?
1 1 Exit: something(4) ?
X = 4
(1 ms) yes
{debug}
