There are a dozen of these tools now and their marketing pages have converged to the point where you can't tell them apart by reading them. Everyone is "#1". Everyone is "100% undetectable". Nobody explains how any of it works.
This guide is the mechanics. Not a ranked list — that's a separate post — but what these products actually do, where they differ architecturally, and how to tell a checkable claim from an unfalsifiable one.
What an AI interview assistant does
Strip the marketing and there are three capabilities. Most tools have one or two; a few have all three.
Listening. Real-time transcription of the conversation — usually both your microphone and your system audio, so it hears the interviewer through your speakers as well as you. This is what makes a tool useful in a spoken interview.
Seeing. Reading what's on your screen: a coding problem, a diagram, a spec. Sometimes called capture mode or screen analysis. This is what makes a tool useful in a written test, where the question is never said out loud.
Answering. Turning either input into something you can use — a formatted answer, working code, a talking point. The differences here are less about model quality (most use the same frontier models) and more about when the answer appears.
That last point matters more than vendors emphasise. Some tools answer when you press a key. Others follow the conversation and surface an answer as the question is asked. The gap between those two is the gap between doing something visible and doing nothing at all.
Where detection actually happens
"Undetectable" gets used as if it means one thing. It doesn't. There are separate surfaces, and a tool can be invisible on some while being obvious on others.
The screen share. Whether the tool appears in the pixel stream sent to the interviewer. This is what most people mean, and it's the easiest to achieve — window-level exclusion is well-trodden. What screen sharing actually captures covers this in detail.
The process list. Whether the tool appears in Activity Monitor or Task Manager. Relevant if an interviewer asks you to show running processes, or if proctoring software enumerates them. A tool named after itself fails here; one running under an unremarkable process name doesn't.
The window switcher, dock and taskbar. Alt-tab is the fastest way anyone spots an app they weren't expecting.
Focus events. If clicking the tool makes it the active window, the app you were sharing visibly loses focus.
Input. Some assessment platforms log keyboard events. If a tool is driven by keyboard shortcuts, every command is a logged event with a timestamp. This surface is the one almost nobody discusses.
The browser. If the tool runs in a tab, it's inside the most inspected surface on the machine — a browser extension can enumerate tabs and windows, and that's where a lot of proctoring lives.
A product can be genuinely invisible on the screen share and completely visible in the process list. Both claims can be true simultaneously, which is why "undetectable" on its own tells you nothing.
Native app versus browser tool
The single biggest architectural split in the category.
Browser-based tools run in a tab. They work on machines you can't install software on, which is a real advantage — a locked-down work laptop, a lab machine. The tradeoff is that a tab is enumerable by anything with browser-level access.
Native desktop apps install on the machine. They can integrate below the level that capture software reads, and they're outside the browser's visibility. The tradeoff is that you need permission to install, and they're platform-specific.
Neither is universally correct. The question is which surface matters for the room you'll be in.
How to evaluate a claim
Vendors make two kinds of statement, and only one is worth anything.
Outcome claims describe what someone would notice: "nothing the interviewer can see", "no visible overlay", "runs quietly in the background". These are usually true and completely unfalsifiable. They say nothing about the process list, the window switcher or input logging.
Mechanism claims describe where the software sits: "absent from the dock, menu bar and Activity Monitor", "runs under this process name", "click-through, never becomes the active window". These are specific enough that you can verify them yourself in a minute.
Prefer the second kind. Not because mechanism claims are automatically true, but because a vendor making them has exposed itself to being checked — and you can do the checking.
Two red flags worth naming:
Absolutes. "Has never been detected" and "zero documented cases" are claims about every use by every user on every platform version, past and future. Nobody can know that. Watch for phrasing like "when used properly", which quietly converts any failure into user error.
Version-pinned guarantees. One vendor states its invisibility applies to "Zoom 6.16 and below" — which is admirably honest, and also tells you the guarantee has an expiry date. Praise the honesty; understand the limit.
The pricing patterns to watch
Three things make headline prices misleading in this category:
Feature-gated undetectability. At least one popular tool advertises $19.99/month while the plan that's actually hidden from screen sharing costs $149.99/month. Check that the tier you're quoted includes what you're buying it for.
Credits. Metered usage sounds fine until you're forty minutes into an interview watching a balance. Unlimited plans and credit plans are not comparable on price alone.
No published price. Two widely recommended tools show tier names and no numbers — you find out during signup. That's a choice they made, and it's reasonable to weigh it.
For the actual numbers, the cheapest tools ranked on published price has the comparison.
What these tools are bad at
Worth stating plainly, because no vendor will:
- They don't fix eye movement. Reading off a screen looks like reading off a screen.
- They don't make you sound natural. A long silence followed by a fluent, complete, slightly over-structured answer is a pattern people notice.
- They can't help with what you don't understand. If a follow-up probes one layer deeper than the answer you read out, you're on your own — and that's exactly what follow-ups are for.
- They don't know your résumé's specifics unless you give them your context first.
- They're not a substitute for preparation. The people who get the most out of these tools are the ones who least need them.
A Word of Caution
Relying solely on a tool to provide answers you don't understand is a risky strategy. True professional growth comes from learning, not just passing a test.
There's also a policy dimension. A live job interview, a take-home, and a proctored certification exam carry different rules and different consequences, and some of those rules are contractual or institutional. Whether to use a tool in a given context is a decision worth making deliberately rather than by default. Whether using AI in an interview counts as cheating goes into it properly.
A checklist before you buy
- Which surfaces does it claim to be invisible on? Screen share only, or process list too?
- Does it describe mechanism or outcome?
- How is it controlled — keyboard, clicks, or something that leaves no input to log?
- Does it read the screen, or only listen? Decide based on whether your rounds are spoken or written.
- Is usage metered? Are sessions capped?
- Is the price you were quoted the price with the feature you want?
- Can you verify the claims yourself on your own machine before it matters?
Feature Spotlight: Where Velin AI sits on this map
Native desktop app, OS-level rather than overlay-based: absent from dock, menu bar and Activity Monitor, running as V Module, click-through, never the active window. Both listening (live mode) and seeing (capture mode). Controllable by keyboard, undetectable clicks, or custom mouse gestures — the last of which leaves the keyboard surface untouched. Unlimited usage and session length on every plan, from $34/month or $324 once.
The short version
The category is more differentiated than its marketing suggests, but not along the axes the marketing uses. Ask where a tool is invisible rather than whether it is, prefer mechanism claims over outcome claims, check the input surface, and verify on your own machine before it counts.
Next: the tools ranked overall, ranked on documented undetectability, and what a coding round specifically needs.