04-fact-check

name	04-fact-check
description	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.
argument-hint	text

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.