Have Gemini extract each factual claim from a passage, rate it supported / unsupported / needs-source, and explain what evidence would settle the unsupported ones.
The prompt
Fact-check the following passage. Extract each discrete factual claim. For each, label it SUPPORTED, UNSUPPORTED, or NEEDS-SOURCE, give a one-line reason, and note what evidence would confirm it. Do not rewrite the passage; only assess it. Passage: [PASTE].
Replace the variables
[PASTE]The text to check, up to a few paragraphs.
Which model to use
- Gemini 3.6 Flash — Claim extraction is fast and cheap; Flash handles it well.
Example input
- [PASTE] = a marketing paragraph with three statistics.
Example output
We only publish example outputs from real model runs. This template has not been formally tested yet, so no output is shown. Run it yourself with the input above.
Why this structure works
- Per-claim labelling stops one wrong number from discrediting the whole passage.
- Asking for the confirming evidence turns the output into a to-do list.
Common failures & fixes
The checker asserts SUPPORTED without a source.
Fix: Require a citation for any SUPPORTED label, or downgrade to NEEDS-SOURCE.
Known limitations
- The model may not know recent facts; enable grounding where possible.