The General Prologue of the Canterbury Tales describes the twenty-nine people travelling on the pilgrimage to the shrine of Thomas a Becket in Canterbury. The Reeve is the twenty-third person described, and is otherwise known as the an overseer of his master’s lands and property.
"The reeve he was a slender, choleric man (page 19, line 588)."
Choleric means "bad-tempered or irritable," showing that Chaucer clearly characterizes the reeve as being easily angered.
"Well could he manage granary and bin; no auditor could ever on him win (page 19, line 594-595)."
Here, Chaucer explains the way in which the reeve does his job, stating that he knew his trade so well and executed his duties so precisely that no auditor could ever make money off of him. This directly characterizes the reeve as meticulous.
"Yet no man ever found him in arrears. There was no agent, hind, or herd who'd cheat but he knew well his cunning and deceit (page 19, line 603-605)."
The reeve's intuitive nature is directly characterized here as well, when Chaucer explains that he was always able to tell lies from truths in both the manner of his superiors and inferiors.
"Right rich he was in his own private right, seeing he'd pleased his lord, by day or night, by giving him, or lending of his goods, and so got thanked- but yet got coats and and hoods (page 20, line 610-613)."
It is possible to discern that the reeve is cunning and clever because he had accumulated a small profit by "lending" his lord possessions that he claimed were his own. In fact, they were the already the lord's objects, but he convinced his lord so well that he received those objects and other compensations in return for those possessions.
"And at his side he bore a rusty blade (page 20, line 619)."
Chaucer may be leading the reader to conclude that the reeve is cheap and frugal because he carries a blade that is old and rusty. The question presents itself as to why the reeve would carry such an invaluable blade when he could afford a much more effective one.
"And ever he rode hindmost of our troop (page 20, line 623)."
This indirect characterization suggests that the reeve was very mistrusting and suspicious, as he refused to ride anywhere but at the back of the procession all the way to Canterbury and back.
The three adjectives that would best describe the reeve would be ill-tempered, shrewd, and self-serving. Already there have been many examples of his traits, especially ones that define the reeve as cunning and clever, mainly for his own purposes.