Those who meet Tiaumil, it is likely to be while he is at a desk filled with books and papers. The first thing that would be noticed is of course his race, for he is clearly of elven descent, although he has about him slightly sharper features than those normally seen, his face lean and angular, skin paler than the norm that is only highlighted by the whiteness of his hair.
He has been working as a scribe in Candlekeep for numerous years now, something he is exceedingly skilled in and prized for his work there, enough that he can come and go freely from those halls.
For all that he is valued and welcomed in Candlekeep, Tiaumil will never rank highly amongst their number, for unlike the majority, he is not a wizard.
Upon seeing you, he might sit back, his eyes cutting as he takes you in, judging who it is he is facing. There would be a polite smile upon his lips, open to being friendly. He has that look about him, that he could turn a smile and make anyone feel welcome, but there is sharpness there too, one that promises a far less pleasant response should the need call for it. There is a slight cruelness to his lips, or perhaps in the way he observes those who come to him disturbing his task, that hints at something fearful if roused. But on the whole people who meet the scribe find him pleasant and amiable, open to working with others if it fulfils his own wishes too.
Those seeking him may know of his mercurial ways; the give and take of agreements and deals, tit for tat, ones that he is generally reputed to be reliable for. Even a vague question to those who might know of him would find the knowledge of his wants easily: Spells.
Tiaumil, despite not being a wizard, has with him a spellbook, and more often than not he can be found copying spell theory or spells themselves into its pages, the swoop of elegant handwriting quickly filling those pages. It has been thus for as long as most have ever known him, and what brought him to Candlekeep in the first place.
But he has left those lauded halls for the moment, the thirst for rare spellcraft bringing him to the sword coast and the Planar Beacon there at the word from a colleague, a far cry from the luxury he is used to. It is there that people might find him, if they were looking, the elf working alongside the simulacrum of Zatharius without any evident issue.