From Fate's Harvest
Contracts are a set, formal agreement with broad purviews of the Wyrd that anyone can use and 'sign' their name to.
Goblin Vows, on the other hand, while still made with purviews of the Wyrd, are far more restrictive, and far less convenient.
In essence, you get to make a one-sided mini-Contract clause on the fly as the Boon of an impromptu pledge, with a steep Task.
| Goblin vows all have only: