Supported document type
Detect tampered and deepfake Cover Letter
Whether a cover letter was written by AI is not a question the prose alone can settle: a well-prompted model writes cleaner applications than most candidates, and style is not evidence. What is checkable sits around the prose - an employer named in the fourth paragraph who belongs to a different application, claims of experience the attached CV does not support, and a file whose creation history shows it was printed from a browser rather than written in one sitting. Those are findings a reviewer can act on.
API slug: cover_letter
Last updated:
What a genuine cover letter contains
A cover letter is mostly free text, which is exactly why its structured parts matter. It opens with the candidate's contact block and a date, addresses a named person and their title, cites the role and often a requisition or reference number, then argues: a paragraph tying the candidate to this specific employer, evidence paragraphs naming employers, dates, projects and outcomes, and a close. It ends with a sign-off, the candidate's name and, where it is sent as a document rather than an email body, a signature.
Nothing inside a cover letter cross-checks anything else, so its claims are constrained from outside. Every employer, job title and date it names has to match the CV it was sent with, and the addressee and company have to be the ones the application actually went to. The name in the sign-off should match the account that sent the file and the author recorded in the document's properties. A letter contradicting its own attachments is the ordinary failure mode here.
How cover letter forgeries are made
Bulk generation with a name swap
One letter is produced for dozens of applications with the company and role fields replaced each time. The replacement misses an occurrence, so a paragraph praises a competitor's mission or the salutation and the body name different organisations. This is the single most common tell in an application pile.
Experience invented against the CV
The letter claims a role, a team size or a span of years the attached CV does not support. Free text carries no field validation, so the claim only surfaces when someone reads the two documents against each other, which is why this contradiction often survives as far as the interview.
Model-drafted prose printed to PDF
A chat response is pasted into a document or printed straight out of a browser. The resulting file records the generating application in its properties, uses the default font stack of a web page rather than a word processor, and usually keeps the spacing conventions of the tool that made it.
A borrowed letter with the header replaced
Sample letters published by career sites are downloaded and edited down to the contact block. The body keeps phrasing that turns up verbatim in other applications, and the edited header belongs to a different rendering pass from the text below it.
An application sent by someone other than the candidate
Agencies and paid writers submit on a candidate's behalf, so the name in the sign-off, the author recorded in the file, and the sending address disagree with each other. It is not always fraud, but it changes who the employer is really assessing, and it is visible in the document's properties.
What TamperCheck checks on a cover letter
TamperCheck runs 200+ forensic checks across three layers and returns a risk score from 0 to 100 with plain-English findings tied to specific regions of the document. These three carry the most weight on this document class.
Signature forgery analysis
Signature regions are assessed for ink consistency and for how the stroke sits on the page, which distinguishes a genuine pen stroke from a pasted image of one.
Date and validity consistency
Issue, expiry, and period dates are checked against one another and against the file's own creation metadata, which catches backdating and validity extension.
Reference and document number checks
Document, account, and reference numbers are checked for issuer format conformance and against every other place the same value appears on the page.
And many more checks
The three above are the layers that carry the most weight on a cover letter. Every upload runs the full suite of 200+ checks regardless of document class, spanning file structure and metadata, pixel-level forensics, font and text rendering, optical and print characteristics, provenance signals, AI-generation signatures, and many more checks.
Who verifies a cover letter, and why
Hiring managers and admissions teams screening applications. In each case the document is being used to unlock money, access, or a legal status, which is exactly what makes it worth forging.
How to verify a cover letter in 4 steps
Check the fields against each other
Read claimed experience, employer references, and dates together rather than one at a time. Forgers typically change one value and leave the rest of the document describing the original.
Inspect the file metadata
Open the document properties and look at the producer, creation date, and modification date. A document produced by a consumer PDF editor, or created long after the date printed on its face, is worth a closer look.
Ask for a second document
Request a corroborating document from the same issuer or an adjacent period. Forgery effort concentrates on one file, so inconsistencies surface as soon as there are two to compare.
Run a forensic check
Manual review catches obvious edits but not field-level pixel manipulation or synthetic generation. TamperCheck runs 200+ forensic checks on a cover letter and returns a risk score from 0 to 100 within seconds, at $0.50 per document.
Frequently asked questions
Can recruiters tell if a cover letter was written by AI?
Not reliably from the writing itself, and any tool claiming a definitive verdict on authorship from prose alone deserves suspicion. What recruiters can establish is more useful: whether the letter names the wrong employer, whether its claims survive comparison with the CV, and what the file's creation history says about how it was produced. Those are checkable things; writing style is not.
How do I verify candidate application documents?
Verify the documents carrying structured claims first, meaning the experience letters, relieving letters and certificates, and treat the CV and cover letter as the statement those documents have to support. Read the pack as one unit, since employers, titles and dates must agree across every file. TamperCheck scores each file from 0 to 100 and reports the regions that were edited, at $0.50 a document with no subscription.
Does an AI-written cover letter matter if the candidate is qualified?
It matters only where it conceals something, which is the useful way to treat it. A model-written letter from a candidate whose experience letters hold up is a writing-assistance question for the employer's own policy to settle. The same letter sitting beside a fabricated experience letter or a reference that leads nowhere is part of a pattern, and patterns are what screening exists to find.
What should I check when a cover letter and CV disagree?
Go to the source documents instead of asking the candidate to explain. Where the letter claims a title or a tenure the CV does not, the experience letter from that employer settles it, and that letter is the one worth checking forensically. A disagreement between two documents the candidate wrote is weak evidence; a disagreement with a document an employer issued is not.
TamperCheck analyses cover letter uploads with a hybrid forensic and AI pipeline tuned for this document class. Upload endpoints accept PDF and common image formats; class is inferred automatically. See the API & MCP documentation for authentication, async jobs, and webhooks.