The Healers' Road is a book about love; whether that be romantic, familial, or fraternal; and the bonds of belonging and obligation it creates between us.
I'll start with the negative, because that's always the best place to start with a book I liked and would highly recommend. There's not a lot to dislike, though there's certainly elements that could be better. Robertson's prose is mediocre; it's not bad, or amateurish, but it's not something to recommend the novel on. The pacing is meandering, occasionally to the point of disorientation or query; a character breaks their arm at one point, for instance, and this is a significant plot point, and then half a dozen chapters later it ceases to be an issue, such that I was unclear on whether they'd fully healed or if it just wasn't bothering them anymore.
To an extent though, this works with the framing of the novel; it's set over the course of two years following a trade caravan, and so focus inherently narrows when the caravan stops or when there are notable events happening, broadening again to skip over weeks or months in transit or without notable happenings. It's not an epistolary novel, though it has shades of it, and indeed letter-writing is a major focus of Agna, one of the two protagonists.
Where Robertson really excels, and what makes the novel worth recommendation, is in characterisation. The novel is tightly focused around the two protagonists, with only the barest flitting to an occasional external POV, and greatly benefits from this focus and the ability to delve into them deeply as characters.
Both Keifon and Agna are, initially, very unlikable characters, though not in a negative way for the reader, and both have their reasons for being so. Agna is a spoilt rich girl with little perspective, who views her healing arts as largely a side endevour; a respectable profession for a young woman of standing, and something to show her parents that she's capable of knuckling down and putting in work. Keifon, meanwhile, is irritable and standoffish to the point of hostility, and while he isn't outwardly dogmatic about his religion his internal monologue makes it clear he considers Agna and most others he meets to be godless sinners and infidels, if perhaps well-meaning ones.
Robertson shows an excellent understanding of why people develop flaws and views like this, however. Both Keifon and Agna have plenty of negative characteristics, but they have understandable and relatable reasons for these. Agna comes off as entitled and stuck-up, treating people like servants, but it's clear she has major self-esteem issues and fundamentally struggles to understand why strangers would do things to help her without expecting to be paid for their time. Keifon is painfully aware of his status as a foreigner and an outcast on the run from his past, and expects people to see him as such; a dangerous but useful outsider to be treated with polite hostility and wariness, and chased out of town the moment that balance tips too far away from usefulness.
I'm a big fan of religion and religious characters in fantasy, and Robertson excels here with Keifon, painting a detailed and sympathetic portrait of a man who has anchored his life around religion out of neccessity as much as desire, who is fulfilled by it personally but at the same time distanced by it from others. There's the occasional stumble in worldbuilding; Keifon is explicitly in the military, for instance, something key to his character, but he doesn't seem to have a rank and it's unclear why he's on loan to a fantasy equivalent of the Red Cross/MSF, but this doesn't detract from the novel overall.
The novel epitomises that which I like best about its subgenre; it's not quite cozy fantasy, to me, but it's low-stakes fantasy, and uses this to tell a story focused around character development and exploration instead of dramatic, world-changing events. An excellent debut, and one that leaves me looking forward to reading more by the author.