SrtaA First off, I enjoy your title! I like that the maiden is the mischievous one, and it's the prince who has to sleep his life away. I don't know if that's what your book is actually about, but I like this subversion of gendered tropes! :)
First off, simple fix that again helps EVERYONE: in your first sentence, "Firm knocks ... made Alexa startle in anticipation" -- try to avoid "helping" verbs that dilute the power of your main action words. Startle is a great word, evokes a clear picture and emotional state. "made startle" doesn't really make sense, and your real action "startle" is lost in the rest of the sentence. "Firm knocks at the carriage door startled Alexa and Lady Cordelia." We don't know anything about them yet, so you don't need "the other maiden" here; it just muddles the opening line and slows it down. Also, I'm not positive you can "startle in anticipation." I would go with startle here, and then explain Cordelia turns toward the door in anticipation or something.
Magnus von Wutenfall is SUCH a name omg. Love it.
Alexa's personality is well-established in that first line of dialogue. And her curiosity shows through when she peers outside. Also, "A handsome face showed up." is a fabulous, funny one-liner para.
In general, some of your sentences could be pared down a bit, just to help with the flow. For ex: "peered to the outside" should be "peered outside" ; also, "Alexa's violet eyes met the Prince's golden ones immediately. What she saw was the immediate shock in those eyes." should be "...(keep the first sent)... Shock widened his leonine gaze." (or whatever.) Moral of the story, we don't need two "immediate" anythings, and we don't need "what she saw was" because clearly she saw it, you just told us her eyes met his his, and that's what eyes do.
Love the mercenary and the "honor is to be lost" line, plus the "bastard" line. Your short, pithy sentences are hilarious and great at characterization.
"Concatenate" -- Bold choice. Doesn't quite flow with the story, might be a bit too intense a vocabulary term for the genre, since it's usually used in regards to coding. Also, I had to look that up to make sure I actually knew what it meant, and I have 4 degrees. Your average reader probably doesn't know that word off the top of their head. By all means, use advanced vocab and hold high expectations for your readers, but try to limit the really difficult words to times when no other word is as good.
"Le mot juste" is a French phrase that essentially means "the perfect word." It's this idea that sometimes, authors find the absolute perfect word for a sentence or an idea, and when it comes together, it forms the most perfect sentiment. I don't think concatenate is "le mot juste" in that moment. Instead of perfectly flowing within the string of words around it, it stood out too much and hurt your flow.
Okay, General Thoughts:
Pros: Interesting historical period setting, great characterization of Alexa and Cordelia. Strong visual descriptions. Cordelia's description para was especially strong. Lovely vocabulary/diction. Some really funny lines. Great high-stakes ending for a first chapter. Solid build-up of the initial mystery--Who, or what, is Alexa? Why do people either hate or love her? Why does everyone think she may have assassinated a prince?
Great opening in terms of story!
Cons: Story-wise, the only light issue with the first chap is that the mysterious accident "two days ago" is more intriguing than the current predicament. I'd suggest including a few more details about what happened to her hands, how she saved people, who she was fighting, etc. You don't need too many or anything, but a few more details would help slake the hunger for backstory I was feeling.
Grammar-wise, few small issues. As I've already mentioned, sentence structure is sometimes a little wordier than it needs to be, or rather, ordered a bit strangely to mess up the flow. Watch your prepositions like "out" "of" etc.
For ex "watchful of the noble couple's clash of glances" is a bit awkward. Stick with "watching the noble couple's clash of glances"; "instinct of preservation" = "preservation instinct". Changes like this tighten up the language so the reader doesn't get bogged down so often.
All in all, intriguing opening and all the makings of a fascinating tale! Keep up the great work with characterization, imagery, and diction; with a few tweaks to sentence construction, you'll be all the stronger a storyteller! :)