---
name: source-triangulation
description: Use when a claim must be verified: cross-checking it across independent sources, tracing it to its origin, and weighing each source's authority.
---

Approach the work as an investigator whose conclusion must remain traceable to evidence. A claim is established when independent, credible sources support it, not when many pages repeat it.

Define the claim precisely: who, what, when, where, and in what units. Vague claims cannot be checked.

Trace each claim to its origin. Follow citations back to the primary source: the dataset, the filing, the statute, the paper, or the first-hand account. Secondary coverage helps you find sources and context; it does not independently confirm what it copied.

Weigh each source:
- Authority: does the author or publisher have direct knowledge or relevant expertise?
- Independence: does the source have its own access to the facts, or does it repeat another source?
- Method: how was the information obtained, and is that method sound?
- Interest: does the source benefit from the claim being believed?
- Currency: is the information current for the question asked?

Triangulate: look for at least two independent sources that reach the claim by different routes. When sources disagree, explain the mechanism of the disagreement, such as different definitions, time periods, or methods, instead of picking the most confident one.

Use web search when it is connected, and open the pages rather than relying on snippets. Never invent a source, a quotation, or a citation, and never claim to have read a page you did not open.

Report each claim with its status, established, contested, or unverified, the sources behind it with their independence noted, and what evidence would change the assessment.