Install any skill in seconds. Free to start, no credit card required.
Get Started Free →Run a claim-by-claim fact-check pass on a draft article, script, or report before publication. Use when asked to fact-check a piece, verify claims before publishing, or do editorial verification. Produces a claim inventory (every checkable assertion pulled out), a verification status and source for each (confirmed / needs sourcing / unverifiable / wrong), the fixes, and a flag on the high-risk claims (numbers, quotes, names, legal/defamatory statements) that must not go out unverified.
.claude/skills/mohitagw15856-fact-check-pass/SKILL.md| Test case | Without → With | Effect | Δ tokens | Δ turns |
|---|---|---|---|---|
| case-04 | ✗→✓ | ▲ Improved | 126% | 0% |
| case-08 | ✗→✓ | ▲ Improved | 161% | 0% |
| case-09 | ✗→✓ | ▲ Improved | 31% | 0% |
| case-12 | ✗→✓ | ▲ Improved | 41% | 0% |
| case-14 | ✗→✓ | ▲ Improved | 11% | 0% |
Everything in a published piece is a claim someone can be wrong about — a date, a number, a quote, an implication. This skill does what a good fact-checker does: it pulls every checkable assertion out of the prose, verifies each against a source, and stops the high-risk ones (stats, quotes, anything defamatory) from going out on a "probably right."
Given the draft, produce the claim inventory and status — check what you can against the provided/known sources, and for anything you can't verify, mark it clearly rather than guessing. Never assert a fact is confirmed without a basis.
Ask for (if not provided, else infer and label):
Every checkable assertion extracted:
| # | Claim (as written) | Type | Status | Source / basis | Fix | |---|---|---|---|---|---|
The claims that must not publish unverified — statistics, direct quotes and their attribution, named individuals (especially any allegation), superlatives ("first," "only," "largest"), and anything potentially defamatory. Each with what's needed to clear it.
For every 🔴/⚠️: the correction, a hedge to the supportable version, or "cut it." For 🟡: the source to obtain.
What's still open before this can publish, and a note that quotes should be confirmed with the speaker/transcript and legal review sought for anything defamatory.
| Case | Status | Duration (ms) | Turns | Tokens | Tool calls | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Without | With | Δ | Without | With | Δ | Without | With | Δ | Without | With | Δ | ||
case-01 | fail→fail | 5,070 | 6,241 | +23% | 1 | 1 | 0% | 1,017 | 1,782 | +75% | 0 | 0 | — |
case-02 | pass→pass | 14,093 | 9,813 | -30% | 1 | 1 | 0% | 2,178 | 2,305 | +6% | 0 | 0 | — |
case-03 | pass→pass | 13,230 | 12,312 | -7% | 1 | 1 | 0% | 2,391 | 2,826 | +18% | 0 | 0 | — |
case-04 | fail→pass | 5,761 | 9,971 | +73% | 1 | 1 | 0% | 1,144 | 2,582 | +126% | 0 | 0 | — |
case-05 | pass→pass | 7,775 | 9,615 | +24% | 1 | 1 | 0% | 1,341 | 2,437 | +82% | 0 | 0 | — |
case-06 | pass→pass | 8,528 | 9,366 | +10% | 1 | 1 | 0% | 1,457 | 2,526 | +73% | 0 | 0 | — |
case-07 | pass→pass | 9,579 | 9,554 | -0% | 1 | 1 | 0% | 1,688 | 2,432 | +44% | 0 | 0 | — |
case-08 | fail→pass | 4,211 | 6,784 | +61% | 1 | 1 | 0% | 873 | 2,275 | +161% | 0 | 0 | — |
case-09 | fail→pass | 11,211 | 10,958 | -2% | 1 | 1 | 0% | 1,984 | 2,600 | +31% | 0 | 0 | — |
case-10 | pass→pass | 9,478 | 11,469 | +21% | 1 | 1 | 0% | 1,717 | 2,640 | +54% | 0 | 0 | — |
case-11 | fail→fail | 1,853 | 2,037 | +10% | 1 | 1 | 0% | 361 | 1,019 | +182% | 0 | 0 | — |
case-12 | fail→pass | 7,697 | 8,901 | +16% | 1 | 1 | 0% | 1,544 | 2,183 | +41% | 0 | 0 | — |
case-13 | fail→fail | 3,675 | 7,304 | +99% | 1 | 1 | 0% | 658 | 1,996 | +203% | 0 | 0 | — |
case-14 | fail→pass | 11,058 | 8,729 | -21% | 1 | 1 | 0% | 2,019 | 2,233 | +11% | 0 | 0 | — |
case-15 | fail→pass | 10,282 | 10,210 | -1% | 1 | 1 | 0% | 2,072 | 2,576 | +24% | 0 | 0 | — |
case-16 | pass→pass | 12,605 | 12,947 | +3% | 1 | 1 | 0% | 2,145 | 2,877 | +34% | 0 | 0 | — |
case-17 | pass→pass | 4,213 | 2,793 | -34% | 1 | 1 | 0% | 732 | 1,117 | +53% | 0 | 0 | — |
case-18 | fail→pass | 8,449 | 9,894 | +17% | 1 | 1 | 0% | 1,480 | 2,423 | +64% | 0 | 0 | — |
case-19 | pass→pass | 6,222 | 7,745 | +24% | 1 | 1 | 0% | 1,192 | 2,014 | +69% | 0 | 0 | — |
case-20 | pass→pass | 3,139 | 3,774 | +20% | 1 | 1 | 0% | 595 | 1,304 | +119% | 0 | 0 | — |
case-21 | pass→fail | 10,455 | 16,377 | +57% | 1 | 1 | 0% | 1,814 | 3,934 | +117% | 0 | 0 | — |
case-22 | pass→fail | 8,327 | 11,685 | +40% | 1 | 1 | 0% | 1,724 | 2,691 | +56% | 0 | 0 | — |
DecimalAI ran this skill against gemini-3.6-flash twice over the same eval suite — once with the skill loaded and once without — and compared the two runs case by case. 22 cases were attempted. The headline lift of +23 percentage points is the difference between those two pass rates over the 22 comparable cases. 2 cases got worse with the skill loaded, and they are included in that figure.
Without the skill loaded, the model failed this case. With it loaded, the same prompt on the same model passed. This is one improved case from the latest verified run; every case, including any that regressed, is in the table above.
Other measured skills in the registry, with their headline benchmark lift.