Fact-check
Verifies the factual claims inside a target text and rewrites it grounded in evidence. The skill extracts each verifiable claim, runs a cheapest-first verification cascade, and emits a rewritten answer where every confirmed claim carries a footnote citation and every unconfirmed claim is explicitly hedged. When sources disagree, both are reported rather than one being silently chosen.
Actions
| # |
Action |
Role |
Input |
| 01 |
identify-claims |
Extract verifiable factual claims from the text, classify each, drop opinion |
target text |
| 02 |
verify |
Run the verification cascade per claim, produce a verdict and sources |
claim list from 01 |
| 03 |
report |
Rewrite the text with footnote citations, hedge unverified, surface conflicts |
verdict list from 02 |
Run 01 → 02 → 03; pass each ## Test before the next.
Before running an action, read its file in actions/, not only the table or assets.
Transversal rules
- Never alter the meaning of a claim while verifying it: verify what was stated, not a charitable reinterpretation.
- The verification cascade is cheapest-first and short-circuits: stop at the first tier that resolves a claim. See
references/verification-cascade.md.
- A web lookup is the last resort, never the first. Reach it only when project memory and codebase inspection both fail to resolve a claim.
- Claim categories come from the locked set in
references/claim-categories.md. Opinion, preference, and trivially-known statements are not claims and are skipped.
- When two sources disagree, report both with their origin, never silently pick one.
- An unverified claim is never deleted and never asserted as fact: it is kept and marked
(unverified - no source found).
- Caching a verified fact is opt-in: propose it with a recommendation, never cache silently. The skill persists nothing; the mechanics live in action 03.
- The final report is reader-facing prose: the corrected text,
## Sources, and ## Unverified claims, nothing else. Internal mechanics never appear in the output: no cascade or tier trace (Cascade:, tier 1/2/3, miss, resolved), no category labels, no raw verdict words. State conclusions, not the process. Action 03 holds the exhaustive forbidden list.
- The report is rendered in plain prose and is never restyled by an active output mode. The skill's output format is fixed by action 03 alone.
References
references/claim-categories.md: locked taxonomy of verifiable claim categories with definition and example.references/verification-cascade.md: the three-tier cascade, short-circuit rule, web-cost guardrail.
Assets
assets/report-template.md: rewritten-answer skeleton with the ## Sources footnote block.
1---2name: 04-fact-check3description: Verify factual claims in a text against authoritative sources and rewrite it with footnote citations, hedging the unconfirmed. Use to fact-check, verify a claim, or cite sources on request. Not for judging code or clarifying requirements.4---56# Fact-check78Verifies the factual claims inside a target text and rewrites it grounded in evidence. The skill extracts each verifiable claim, runs a cheapest-first verification cascade, and emits a rewritten answer where every confirmed claim carries a footnote citation and every unconfirmed claim is explicitly hedged. When sources disagree, both are reported rather than one being silently chosen.910## Actions1112| # | Action | Role | Input |13| --- | ----------------- | ----------------------------------------------------------------------------- | --------------------------- |14| 01 | `identify-claims` | Extract verifiable factual claims from the text, classify each, drop opinion | target text |15| 02 | `verify` | Run the verification cascade per claim, produce a verdict and sources | claim list from 01 |16| 03 | `report` | Rewrite the text with footnote citations, hedge unverified, surface conflicts | verdict list from 02 |1718Run `01 → 02 → 03`; pass each `## Test` before the next.19Before running an action, read its file in `actions/`, not only the table or assets.2021## Transversal rules2223- Never alter the meaning of a claim while verifying it: verify what was stated, not a charitable reinterpretation.24- The verification cascade is cheapest-first and short-circuits: stop at the first tier that resolves a claim. See `references/verification-cascade.md`.25- A web lookup is the last resort, never the first. Reach it only when project memory and codebase inspection both fail to resolve a claim.26- Claim categories come from the locked set in `references/claim-categories.md`. Opinion, preference, and trivially-known statements are not claims and are skipped.27- When two sources disagree, report both with their origin, never silently pick one.28- An unverified claim is never deleted and never asserted as fact: it is kept and marked `(unverified - no source found)`.29- Caching a verified fact is opt-in: propose it with a recommendation, never cache silently. The skill persists nothing; the mechanics live in action 03.30- The final report is reader-facing prose: the corrected text, `## Sources`, and `## Unverified claims`, nothing else. Internal mechanics never appear in the output: no cascade or tier trace (`Cascade:`, `tier 1/2/3`, `miss`, `resolved`), no category labels, no raw verdict words. State conclusions, not the process. Action 03 holds the exhaustive forbidden list.31- The report is rendered in plain prose and is never restyled by an active output mode. The skill's output format is fixed by action 03 alone.3233## References3435- `references/claim-categories.md`: locked taxonomy of verifiable claim categories with definition and example.36- `references/verification-cascade.md`: the three-tier cascade, short-circuit rule, web-cost guardrail.3738## Assets3940- `assets/report-template.md`: rewritten-answer skeleton with the `## Sources` footnote block.
ai-driven-dev