How to Fact-Check an AI Answer
Break an answer into checkable claims, trace citations to their sources and distinguish false statements from missing evidence.
You'll learn
- Verify individual claims rather than assigning credibility to the whole answer.
- A real citation can still fail to support the sentence beside it.
- Use the relevant source version, date, population and jurisdiction.
- Unsupported, contradicted and unverifiable are different findings.
Fact-checking begins with a sentence precise enough to test. “The study was successful” is vague. “The study found lower error rates in the treatment group after six weeks” identifies an outcome, a comparison and a time frame. Those details tell you what evidence you need.
Work claim by claim
A focused fact-check
Extract consequential claims
Separate dates, quantities, causal statements, attributed views and recommendations. Start with claims that determine the answer.
Define the evidence boundary
Check whether outside research is allowed or whether the task is limited to provided material.
Find the closest relevant source
Use the original report, official documentation or underlying study when appropriate. A source must be authoritative for this particular claim.
Inspect the exact support
Read the surrounding passage, table note or method. Confirm scope, date and limitations.
Record a claim-level verdict
Use the supplied labels. Separate direct contradiction from a source that simply does not address the claim.
Connect the finding to the score
Explain how the unsupported or incorrect claim affects the requested answer.
A citation is a pointer, not a verdict
Evaluation example
- The pilot found that the tool improved speed and accuracy.
- The pilot recorded shorter completion times among 24 volunteers; it did not measure accuracy.
| Finding | What you established |
|---|---|
| Supported | The evidence establishes the claim at the stated scope. |
| Contradicted | Relevant evidence conflicts with the claim. |
| Unsupported by the cited source | The citation does not establish what the answer says. |
| Not verified within the task | You could not establish the claim using permitted evidence and available access. |
Choose sources by fit
An official release can establish what an organization announced. It does not independently prove that the announced product works as claimed. A research paper can establish its own methods and results, but a small study may not support a population-wide conclusion. A search snippet helps locate material; it rarely supplies enough context for the final judgment.
For time-sensitive facts, distinguish publication date from the date the statement concerns. For a rule or guideline, check the relevant version and location. For a quotation, confirm the words, speaker and surrounding context. If access is blocked, record that limit instead of treating a preview as the full source.
Common mistake
Counting repeated articles as independent confirmation
Several pages may repeat the same press release or mistake. Trace the claim back to its origin before calling the evidence corroborated.
Evidence record
- Write the exact claim you checked.
- Record the source title, URL and relevant passage or location where the task permits.
- Check dates, population, units and conditions.
- Explain whether evidence supports, contradicts or leaves the claim unresolved.
- Avoid claiming a complete fact-check after checking only one sentence.
Key takeaway
The useful result is not “I researched it.” It is “This evidence supports this claim, within these limits.”