The Honest Answer
Recruiters cannot reliably detect that a cover letter was written with AI assistance through any real technical tool, since there is no widely trusted, accurate method for this the way there might be for something like academic plagiarism detection in schools. What they absolutely can and do notice, through plain experience built up over hundreds of letters, is a certain generic quality: a letter that could have been sent to any company for any role, with no specific detail that proves you actually researched this particular employer or thought carefully about this specific job opening.
This distinction matters, because it means worrying about detection is largely misplaced energy. The more useful question to ask yourself is whether the letter actually says anything specific at all, regardless of what tool helped you write it.
What Actually Gives It Away
- Generic praise for the company that could apply just as easily to literally any employer in the same industry
- No specific detail about the actual role, product, or team that shows real research went into the application
- Overly smooth, slightly repetitive phrasing that lacks any distinct personal voice throughout the letter
- A structure that mirrors dozens of other AI-assisted letters recruiters have already read that same week, with the same opening and closing patterns every time
- Claims or achievements mentioned that do not quite match what is on the resume submitted alongside it in the same application
Any one of these alone might not raise a flag, but a letter carrying several of them together tends to blur together with every other application a recruiter reads that day.
How to Avoid These Tells
Write the specific reasons you actually want this particular role first, in your own words, before using any tool to help refine the language afterward. Name something concrete about the company or the role that would not apply equally well to a direct competitor down the street. Keep at least one or two sentences that sound distinctly like you, not smoothed into generic professional language, since that small amount of texture is often exactly what makes a letter feel genuine rather than templated and mass-produced for anyone reading it. This same order, your own reasoning first and polish second, is what keeps a resume honest too.
Does This Actually Matter to Your Chances
A generic cover letter, whether AI-assisted or not, has always been a weak part of an application, well before AI writing tools existed at all in any widespread form. The rise of these tools has not really created a new problem so much as made an old one more common and easier to spot, since recruiters now read so many similarly polished but empty letters in a row that a specific, genuine one actually stands out more sharply than it used to just a few years ago.
When a Cover Letter Still Genuinely Helps
A cover letter earns its place most clearly when it explains something your resume cannot on its own, such as a career change, a gap, or a specific reason you are drawn to this exact company rather than a similar one nearby. Used that way, whether AI assisted the phrasing or not, it gives a recruiter real information they could not get from your resume alone, which is the entire point of writing one in the first place rather than skipping it entirely. Ask yourself what genuinely new information the letter adds before you decide it is worth including.
A Quick Checklist Before You Send It
- Does it name the company and role specifically, not in a way that could be swapped for any other employer?
- Does it include at least one detail that shows genuine research into this specific opportunity?
- Do the claims match exactly what your resume says, with no contradictions between the two documents?
- Does at least one sentence sound distinctly like you rather than a smoothed, generic voice?
Running through these four questions before you send takes less than a minute and catches most of the problems that make a cover letter forgettable. Making this check a habit for every application is a small investment that consistently pays off.