Source Cross-Referencer
What This Skill Does
Takes a specific claim and a list of sources you have gathered, then maps which sources support, contradict, or are silent on the claim — so you can see at a glance whether your sourcing is solid before publication.
When To Use This Skill
- You have collected multiple sources on a story and need to know whether they genuinely agree or just appear to
- You are writing a contested claim and want to stress-test whether your sourcing holds up
- An editor has pushed back on a disputed fact and you need to show your evidence clearly
- You are preparing a fact-check package and need a structured comparison of what each source actually says
- You are producing a documentary and need to document that a key claim is independently corroborated
What You Need To Provide
Required: The exact claim you want to cross-reference (one sentence, as it would appear in your story). A list of sources — for each source, paste the relevant excerpt or summarise what it says. Minimum two sources.
Optional: The original context where the claim appears (paragraph or script line). The type of story (news report, documentary, magazine feature, podcast episode). Any known relationship between the sources — for example, if two of them cite the same underlying report.
How the Assistant Approaches This
- Reads the claim precisely as stated — noting any specific numbers, dates, or qualifiers that a source would need to match exactly to count as corroboration.
- Examines each source in turn and places it into one of four categories: Supports (source clearly backs the claim), Partially supports (source agrees with the general point but differs on a detail), Contradicts (source directly disputes the claim or gives a different figure), or Silent (source does not address this specific claim).
- Checks whether sources that appear to agree are actually independent — if two sources trace back to the same original data or rely on the same study, it flags that as a single chain of evidence, not two independent confirmations.
- Produces a structured comparison table followed by a brief narrative summary: what the weight of evidence shows, where genuine disagreement exists, and what gaps remain before the claim can be published with confidence.
Output Format
Two-part output. First, a source comparison table with columns: Source Name / Type (official data, academic study, eyewitness account, etc.) / Position on Claim / Key Quote or Detail / Caveats. Then a short narrative paragraph (three to five sentences) summarising the overall picture: whether the claim is well-corroborated, contested, or undercooked — and what the journalist should do next. Total length: roughly 300–500 words depending on how many sources are provided. Plain language throughout. No legal advice, no editorial opinion beyond the sourcing assessment.
Quality Criteria
Example
Input
Claim to cross-reference: "Ambulance response times in the city's northern district averaged 14 minutes last year, well above the national benchmark of 8 minutes."
Sources:
Regional health authority annual report — "Mean emergency response time across all districts: 11.3 minutes. Northern district recorded the highest mean at 13.8 minutes."
City council budget committee minutes — Councillor quote: "Paramedic shortages have pushed response times in the north to nearly 15 minutes on some nights, which is unacceptable."
National ambulance standards body — Published benchmark: "Target response time for Category 2 emergencies is 18 minutes mean, with an aspirational target of 8 minutes. The 8-minute standard applies only to Category 1 life-threatening calls."
Investigative piece in a regional newspaper — "Northern district response times hit 14 minutes last year, according to health authority data, more than double the national target."
Output
| Source |
Type |
Position on Claim |
Key Detail |
Caveat |
| Regional health authority annual report |
Official government data |
Partially supports |
Records 13.8 min for northern district — close to the claimed 14 min but not identical |
Difference of 0.2 min may matter for accuracy |
| City council budget committee minutes |
Official meeting record |
Partially supports |
References "nearly 15 minutes on some nights" — consistent in direction but this is a peak figure, not an annual average |
Councillor is not citing a specific statistic; this is anecdotal corroboration |
| National ambulance standards body |
Official benchmark |
Contradicts the framing |
The 8-minute standard applies only to Category 1 (life-threatening) calls, not all emergencies |
If your story does not specify call category, the comparison is misleading |
| Regional newspaper |
Secondary source |
Appears to support |
Cites "14 minutes" from health authority data — but is drawing from the same underlying report as your Source 1 |
Not independent corroboration; both traces to the same primary source |
Narrative summary: The claim has solid grounding in official data but two problems need fixing before publication. First, the annual report shows 13.8 minutes, not 14 — a small difference but worth correcting to avoid accuracy challenges. More significantly, the "8-minute national benchmark" framing is contested: the standards body defines that target for life-threatening Category 1 calls only. If the story is comparing all-category averages against a Category 1 target, the comparison is misleading and legally and editorially risky. The regional newspaper piece does not add independent corroboration — it draws on the same health authority data. Recommended next step: confirm the call-category breakdown from the health authority before finalising the claim, and either narrow the benchmark comparison to Category 1 calls or use the 18-minute mean target instead.
Known Limitations
- The assistant cannot access URLs, databases, or documents — it can only assess the information you paste in. If a source excerpt is incomplete or paraphrased, the assessment will only be as good as what you provide.
- This skill does not verify whether the sources themselves are accurate. It maps internal consistency and independence across sources, not ground truth.
- Source categories (Supports / Contradicts / etc.) reflect the claim exactly as worded. If your claim is slightly ambiguous, the assistant will flag that rather than make a judgment call — you may need to tighten the wording first.
- For claims involving legal liability (defamation, privacy), this output is not a substitute for legal review.
Related Skills
1---2name: source-cross-referencer3description: Takes a specific claim and a list of sources you have gathered, then maps which sources support, contradict, or are silent on the claim — so you can see at a glance whether your sourcing is solid before publication.4---5# Source Cross-Referencer67## What This Skill Does8Takes a specific claim and a list of sources you have gathered, then maps which sources support, contradict, or are silent on the claim — so you can see at a glance whether your sourcing is solid before publication.910## When To Use This Skill11- You have collected multiple sources on a story and need to know whether they genuinely agree or just appear to12- You are writing a contested claim and want to stress-test whether your sourcing holds up13- An editor has pushed back on a disputed fact and you need to show your evidence clearly14- You are preparing a fact-check package and need a structured comparison of what each source actually says15- You are producing a documentary and need to document that a key claim is independently corroborated1617## What You Need To Provide18**Required:** The exact claim you want to cross-reference (one sentence, as it would appear in your story). A list of sources — for each source, paste the relevant excerpt or summarise what it says. Minimum two sources.1920**Optional:** The original context where the claim appears (paragraph or script line). The type of story (news report, documentary, magazine feature, podcast episode). Any known relationship between the sources — for example, if two of them cite the same underlying report.2122## How the Assistant Approaches This231. Reads the claim precisely as stated — noting any specific numbers, dates, or qualifiers that a source would need to match exactly to count as corroboration.242. Examines each source in turn and places it into one of four categories: **Supports** (source clearly backs the claim), **Partially supports** (source agrees with the general point but differs on a detail), **Contradicts** (source directly disputes the claim or gives a different figure), or **Silent** (source does not address this specific claim).253. Checks whether sources that appear to agree are actually independent — if two sources trace back to the same original data or rely on the same study, it flags that as a single chain of evidence, not two independent confirmations.264. Produces a structured comparison table followed by a brief narrative summary: what the weight of evidence shows, where genuine disagreement exists, and what gaps remain before the claim can be published with confidence.2728## Output Format29Two-part output. First, a source comparison table with columns: Source Name / Type (official data, academic study, eyewitness account, etc.) / Position on Claim / Key Quote or Detail / Caveats. Then a short narrative paragraph (three to five sentences) summarising the overall picture: whether the claim is well-corroborated, contested, or undercooked — and what the journalist should do next. Total length: roughly 300–500 words depending on how many sources are provided. Plain language throughout. No legal advice, no editorial opinion beyond the sourcing assessment.3031## Quality Criteria32- [ ] Every source provided is assessed and placed in a clear category — nothing left unaddressed33- [ ] The table distinguishes between sources that independently confirm a claim and sources that merely repeat each other34- [ ] Contradictions between sources are named specifically, not smoothed over35- [ ] The narrative summary gives a clear next step — what would strengthen the sourcing, or what is good enough to publish36- [ ] The output does not invent any sources or add information not contained in what the journalist provided3738## Example3940### Input41**Claim to cross-reference:** "Ambulance response times in the city's northern district averaged 14 minutes last year, well above the national benchmark of 8 minutes."4243**Sources:**44451. **Regional health authority annual report** — "Mean emergency response time across all districts: 11.3 minutes. Northern district recorded the highest mean at 13.8 minutes."46472. **City council budget committee minutes** — Councillor quote: "Paramedic shortages have pushed response times in the north to nearly 15 minutes on some nights, which is unacceptable."48493. **National ambulance standards body** — Published benchmark: "Target response time for Category 2 emergencies is 18 minutes mean, with an aspirational target of 8 minutes. The 8-minute standard applies only to Category 1 life-threatening calls."50514. **Investigative piece in a regional newspaper** — "Northern district response times hit 14 minutes last year, according to health authority data, more than double the national target."5253### Output5455| Source | Type | Position on Claim | Key Detail | Caveat |56|---|---|---|---|---|57| Regional health authority annual report | Official government data | Partially supports | Records 13.8 min for northern district — close to the claimed 14 min but not identical | Difference of 0.2 min may matter for accuracy |58| City council budget committee minutes | Official meeting record | Partially supports | References "nearly 15 minutes on some nights" — consistent in direction but this is a peak figure, not an annual average | Councillor is not citing a specific statistic; this is anecdotal corroboration |59| National ambulance standards body | Official benchmark | Contradicts the framing | The 8-minute standard applies only to Category 1 (life-threatening) calls, not all emergencies | If your story does not specify call category, the comparison is misleading |60| Regional newspaper | Secondary source | Appears to support | Cites "14 minutes" from health authority data — but is drawing from the same underlying report as your Source 1 | Not independent corroboration; both traces to the same primary source |6162**Narrative summary:** The claim has solid grounding in official data but two problems need fixing before publication. First, the annual report shows 13.8 minutes, not 14 — a small difference but worth correcting to avoid accuracy challenges. More significantly, the "8-minute national benchmark" framing is contested: the standards body defines that target for life-threatening Category 1 calls only. If the story is comparing all-category averages against a Category 1 target, the comparison is misleading and legally and editorially risky. The regional newspaper piece does not add independent corroboration — it draws on the same health authority data. Recommended next step: confirm the call-category breakdown from the health authority before finalising the claim, and either narrow the benchmark comparison to Category 1 calls or use the 18-minute mean target instead.6364## Known Limitations65- The assistant cannot access URLs, databases, or documents — it can only assess the information you paste in. If a source excerpt is incomplete or paraphrased, the assessment will only be as good as what you provide.66- This skill does not verify whether the sources themselves are accurate. It maps internal consistency and independence across sources, not ground truth.67- Source categories (Supports / Contradicts / etc.) reflect the claim exactly as worded. If your claim is slightly ambiguous, the assistant will flag that rather than make a judgment call — you may need to tighten the wording first.68- For claims involving legal liability (defamation, privacy), this output is not a substitute for legal review.6970## Related Skills71- [source-credibility-brief](../../../magazine-journalism/fact-checking/source-credibility-brief/SKILL.md)72- [statistics-verifier](../statistics-verifier/SKILL.md)73- [claim-verification-checklist](../../../magazine-journalism/fact-checking/claim-verification-checklist/SKILL.md)