From Tapestries MUCK
Flags are set with the @set command.
The flags are: W(izard), S(ticky), L(ink_OK), D(ark), J(ump_OK), K(ill_OK), C(hown_OK), H(aven), A(bode), B(uilder), V(ehicle), and Z(ombie). Many of these flags are overloaded with meanings based on what object type they are on. For example Dark is also Debug on programs, and Sticky is Silent in some cases.
The object type is displayed as a flag letter in the display of a dbref. The letters used are: R(oom), E(xit), F(orth) (for programs) and P(layer) are also used. Things are designated by a lack of a specific flag.