Tom has accomplished many things, despite his lack of experience.
He has a friendship, though strongly disapproved of by his master, with a young witch named Alice Deane. However, both his mother and his master's love, a Lamia witch called Meg have advised him to "treat her better than John treated me and it won't end like this". Tom continues his friendship with Alice, despite the warnings given by the Spook. He also seems to develop some feelings for her, although it is possible that he could be constantly fretting over her because she is the closest thing he ever had to a friend. In the fifth book, she kisses him for the first time, before running off, supposedly to Pendle.
Not much is known about his appearance, although it was written in The Spook's Battle (Revenge of the Witch) that he has green eyes and is left-handed, which seems to be common amongst Spooks. (Bill Arkwright, The Spook and Tom are all left-handed.) Also the American cover of "The Spook's Secret"(Named The Curse Of The Bane in America) shows a picture of him, though it is not very detailed as he is in a hood and cloak.
Mediumship: Tom has the ability to see and speak to the dead, spirits long past, and sense if present
Magical Skill: Although Tom is forbidden to use any form of witchcraft, he and other spooks are cable of witch magic
For example, he used a mirror to talk to Alice, something only a witch could do.
Intimitions of Death: Tom inherited this ability from his mother, Tom can smell death on a person, if the scent is strong
the person is close to being dead, but the fainter the scent the further they're from death.
Time Manipulation: Tom displayed the ability to stop or slow time down in the sixth book, another gift he inherited from
Exculsive knowledge of the Dark: Can read and write Greek, rudementry vocabulary of Latin, and fast learner
Marksmenship: Tom can throw his chain at ten posts and get nine out of ten, he tries not to get full of himself
limited to fight both right and left handed with staff and blade.
Personal Loyalty: Toms greatest strength and weakness, Tom is willing to give his life to protect Alice, his master, and his family
which his enemies often exploit.
Hobble: By some unknow power, Tom has a jinx on himself, meaning that if the Fiend directly killed him the Fiend would only rule
the world for 100 years and then return to where he came from, however if the Fiend wins him over to his side or if his children
kill Tom first, then the hobble becomes absolute.
Sensing: Toms skills at determining who is a witch is becoming more accurate, because he was able to tell in the fourth book that a
servant of the mayors was a witch, even though his master and a retired spook turned priest didn't sense anything.
Immunity/Will power: Like all spooks, Tom is immune to long range sniffing of a witch, but he also shows signs of immunity to temptations of the Old
Gods such as the Bane, Golgoth, and the Fiend showing he has a strong will