Source Eligibility

Definition: Source eligibility is the set of signals and conditions that make a page safe and attractive for an answer engine to cite. An eligible source is clear about what it’s saying (claim-first), who/what it’s about (entity clarity), how it’s structured (definitions, steps, tables, calculators, Q&A), and where the information comes from (evidence pointers), so a model can lift it with low risk.

Scope:

  • Includes: Claim-first content; explicit entities and canonical names; extractable structures (definition, how-to, comparison, calculator, FAQ); up-to-date and non-ambiguous information; stable URLs; basic trust signals (about/author/org context); references to higher-authority specs or docs.
  • Excludes: Purely promotional pages; unstructured walls of prose; content that contradicts itself on the same page; pages that require images/JS to understand the answer; content that hides the claim below the fold.
  • Notes: Eligibility is contextual: different answer engines (Google AI Overviews, Perplexity, Bing/Copilot) emphasize different evidence/recency signals, but all benefit from clearly scoped, well-structured, entity-aware pages.

Why it matters: Even strong, original content will be skipped if the model can’t tell, fast, what the page is about or whether it’s safe to quote. Improving source eligibility is how challenger brands show up next to bigger domains: you make the answer visible, name the entities, and point to credible references. It also makes your content easier to reuse in RAG/agent flows and internal tooling.

See also:
Answer Engine Optimization (AEO); AI Overviews; Entity; Entity-rich content; Format discipline; Definition page; How-to page; Comparison page; Calculator page; Prompt-compatible copy; Answer debt

References