Why AI makes mistakes
Grounding and retrieval
Grounding connects an answer to supplied evidence. Retrieval can reduce unsupported invention, but it can also fetch irrelevant, stale, or conflicting material.
1Try it yourself
Simulation game
Hallucination hunt
Stamp each claim: Trap or Trust. Confident voice ≠ true.
Quiz show
“Sydney is the capital of Australia.”
2Learn the idea
Read
The core idea
See it
Confidence is a tone — verify before you act
Grounding connects an answer to supplied evidence. Retrieval can reduce unsupported invention, but it can also fetch irrelevant, stale, or conflicting material.
Read
A practical lens
Use this three-part method:
- Inspect what was retrieved before judging the answer. Write down what this means in the scenario, what evidence would show it was done, and who owns the decision.
- Require the answer to stay within supplied evidence. Write down what this means in the scenario, what evidence would show it was done, and who owns the decision.
- Surface conflicts and missing coverage. Write down what this means in the scenario, what evidence would show it was done, and who owns the decision.
Read
Worked example
Walk through A support assistant answers from an approved policy library but retrieves a page for the wrong country.. Label three moments where “Grounding and retrieval” changes what you trust: (1) the first fluent answer, (2) the first missing source or permission, and (3) the decision a human must own. Write the before/after task so the model only does the slice that evidence supports. Keep one sentence that states how this page’s idea differs from a generic “AI is smart/dumb” score.
Read
Common traps and better moves
- Assuming search removes hallucinations. This shortcut removes useful friction, but it also hides an assumption that should be tested. Replace it with an observable check.
- Hiding source passages from reviewers. This shortcut removes useful friction, but it also hides an assumption that should be tested. Replace it with an observable check.
- Letting retrieved text override the user’s actual question. This shortcut removes useful friction, but it also hides an assumption that should be tested. Replace it with an observable check.
Read
Build the habit
Before you close the tab, capture a reusable habit for Grounding and retrieval inside Why AI makes mistakes: name the observable check, the evidence you would open, and the stop condition. Rehearse it once on a low-stakes example, then once on a higher-stakes variant. The habit succeeds when you can explain the check without reopening this lesson. Target outcome: Explain why plausible language generation does not guarantee factual accuracy.
Go deeper
Before you start
Why this matters
A support assistant answers from an approved policy library but retrieves a page for the wrong country.
In the wild
See how this idea shows up as a product and a company — then come back to the lesson. Skills transfer across vendors.
Related lessons
Check your understanding
Page assessment
Answer from memory. Completion is saved from this evidence, not from opening the next page.
Local focus for Grounding and retrieval (Why AI makes mistakes): write the smallest test that would falsify a confident claim on this page, name the evidence you would open first, and note who must approve if the cost of being wrong is more than a redo. Keep the note under ten lines so you will actually reuse it.
All responses are required.