The Missing Manual
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Updated Jun 30, 2026

Verification Habits

You do not need to verify everything the AI tells you. That would defeat the point of using it. What you need is a quick instinct for which answers to check, and a few habits that make checking fast. The goal is to spend your skepticism where it pays off - on the claims that would actually hurt if they were wrong.

The one question that sorts everything

Before you act on an AI answer, ask yourself: what happens if this is wrong?

If the answer is "nothing much" - it is a brainstorm, a first draft, a rough explanation to get you oriented - then use it freely and move on. If the answer is "I'd send a wrong number to my boss," "I'd take the wrong medication," "I'd cite a case that does not exist," or "I'd make a decision I can't undo," then you check before you act. That single question does most of the sorting for you.

Everything below is about making the "I need to check" path cheap.

Ask for sources - and actually open them

When something matters, ask the AI where it got the claim: "What's your source for that?" or "Cite where this comes from."

This helps in two ways. First, some tools will search the web and link real pages, which you can open and read yourself. Second - and this is the underrated part - asking for a source is a stress test. If the AI starts producing a vague non-answer, or a link that does not resolve, or a citation you cannot find when you search for it, that is a strong signal the underlying claim was shaky.

The non-negotiable rule: a citation is not verification until you open it. The AI can produce a real-looking source for a false claim, and it can also cite a real source that does not actually say what the AI claims it says. Click through. Read the relevant bit. Confirm the source exists and supports the point.

Cross-check the claims that matter

For important facts, do not take one answer as the answer. Quick ways to cross-check:

  • Search it yourself. Paste the specific claim - the number, the name, the quote - into a regular search engine. Real facts surface from independent places. Invented ones tend to trace back to nothing, or only to AI-generated content.
  • Ask twice, fresh. Open a new conversation and ask the same question differently. If you get two materially different answers, neither is trustworthy yet.
  • Check against a known authority. For a medical, legal, financial, or safety question, confirm against an official or primary source - the actual law, the drug label, the company's own page, a professional you can ask.

You are not running a full investigation. You are spending sixty seconds to confirm the load-bearing facts before you rely on them.

Prefer it for things you can verify

Here is a habit that quietly removes most of the risk: lean on AI hardest for tasks where checking the result is quick.

Some work is self-verifying. If you ask it to write a snippet of code, you can run the code. If you ask it to summarize a document you have, you can compare the summary to the document. If you ask it to reformat a list, you can see whether the list is right. In these cases the AI's tendency to invent is held in check by reality - you will catch a mistake immediately.

Compare that to asking it for a fact you have no way to check - a statistic about an industry you do not know, the details of a study you will never read. There, you are flying blind, fully exposed to whatever it made up. When you can, reshape the task toward the verifiable version. Instead of "What does the law say about X?", give it the actual text and ask "Where in this does it address X?" - now you can check its answer against the words in front of you.

Use it to draft, not to decide

The cleanest line to draw: let AI do the work, but keep the judgment.

Drafting, explaining, brainstorming, summarizing, reformatting, getting unstuck - this is where AI shines, and where a mistake costs you a quick edit, not a bad outcome. Deciding - what to tell a customer, which option to choose, whether a claim is true enough to publish, what advice to follow - stays with you, informed by the draft but not dictated by it.

A useful test before you send or act on anything AI touched: Would I be comfortable if someone asked "how do you know this is right?" If your honest answer is "the AI said so," you are not done yet.

A thirty-second checklist

For anything that matters, run this before you act:

1. What happens if this is wrong?  (Low stakes → ship it. High stakes → continue.)
2. Did I ask for a source - and open it to confirm it says what was claimed?
3. Did I cross-check the load-bearing fact against something independent?
4. Could I explain how I know this is right without saying "the AI told me"?

None of this is heavy. It is a handful of seconds spent on the small fraction of answers where being wrong is expensive. That is the whole trick: not distrusting everything, but knowing exactly where to look - which is what the next phase maps out.