create or replace package test_tags as

    -- %suite
    -- %tags(slow)
    
    -- %beforeall
    procedure slow_setup;

    -- %context(tags_are_applied_in_contexts)

        -- %test
        procedure create_new_mapping;

    -- %endcontext
end;
/

create or replace package body test_tags as

    procedure slow_setup is
    begin
        dbms_output.put_line('slow_setup executed');
    end;

    procedure create_new_mapping is
    begin
        dbms_output.put_line('create_new_mapping executed');
    end;

end;
/

begin
    ut.run('test_tags', a_tags=>'!slow');
end;
/

Finished in .000011 seconds
0 tests, 0 failed, 0 errored, 0 disabled, 0 warning(s)

begin
    ut.run('test_tags', a_tags=>'slow');
end;
/

test_tags
  slow_setup executed

Finished in .002728 seconds
0 tests, 0 failed, 0 errored, 0 disabled, 0 warning(s)

begin
    ut.run('test_tags');
end;
/

test_tags
  slow_setup executed
  tags_are_applied_in_contexts
    create_new_mapping [.002 sec]
    create_new_mapping executed

Finished in .005451 seconds
1 tests, 0 failed, 0 errored, 0 disabled, 0 warning(s)