Which APIs help an agent verify sources?
Arlong, Tavily, Exa and Parallel provide source material for agent workflows; SerpAPI provides structured search-engine results. Their output can help you build a verification workflow, but a URL, relevance score or cited answer alone does not establish independent claim corroboration.
Start with the evidence your application needs. A link identifies a page. An excerpt shows what was retrieved. A supported claim needs an excerpt that actually entails the statement, with the right date, population, unit and scope. Independent corroboration adds another source whose information does not merely repeat the first.
Arlong’s research pipeline includes evidence collection and coverage checks. Its screening boundary is a separate control over what untrusted content may reach an agent. See the API documentation and system whitepaper for the current contracts.
What evidence does each provider expose?
| Provider | Evidence surface | What your application still checks |
|---|---|---|
| Arlong | Screened source evidence, research coverage and response verification links. Docs | Claim support, unresolved requirements and whether sources are independent. |
| Tavily | Ranked results with URLs, content and scores; optional raw content and answer. Search reference | Whether the content supports the claim; a ranking score is not a truth score. |
| Exa | Search results with configurable text and highlights. Search reference | Completeness of retrieved passages and their relationship to each claim. |
| Parallel | Search accepts an objective and returns relevant excerpts. Search quickstart | Whether excerpts cover the whole question; evaluate research products separately. |
| SerpAPI | Structured Google search results, including organic results. Search API | Page extraction, content screening and claim support beyond the result snippet. |
These rows describe the cited interfaces. They do not audit every product from each vendor or establish that an unlisted capability is absent.
How should claim corroboration work in practice?
Consider a report that says adults answered 47% of a financial-literacy index correctly. That does not establish a figure for Gen Z, nor does it show how people plan around inflation. A page can be authentic and still fail to answer your question.
- Write the claim precisely. Record the population, year, measure and denominator before searching.
- Open the primary source. Follow a report link to the underlying table or PDF. Record extraction failures rather than treating a landing-page snippet as the report.
- Attach the supporting passage. Preserve enough context to check qualifications and contradictory findings.
- Trace the upstream origin. Three articles quoting one survey represent one evidence origin, not three independent confirmations.
- Separate unknown from false. If the survey never asked the question, report an absent measure. Do not invent a low percentage.
Screen source content before putting it in model context. Arlong Screen can be used with other providers, so retrieval and screening can be chosen independently. An allowed passage may support an answer; it cannot authorize an action.
How can you test evidence quality before choosing an API?
Build a fixed set of questions with known primary sources and required facts. Include PDFs, conflicting dates, syndicated copies and inaccessible pages. Keep the same extraction budget for each system and save failures as well as successes.
- Source accessibility: could the retrieved page actually be read?
- Requirement coverage: how many requested facts have supporting passages?
- Claim support: does each cited excerpt support the exact assertion?
- Origin diversity: how many independent sources remain after tracing copies?
- Abstention: does the system leave unsupported items unanswered?
Evaluate retrieval without answer generation first. Then test synthesis separately: a fluent answer can conceal missing evidence. Report cost and latency alongside quality, and distinguish classification benchmarks from live-agent security tests.
Where can you inspect the underlying contracts?
The table links directly to the reviewed official API documentation. For integration details, read Exa versus Tavily. For choosing or combining providers, read Tavily alternatives. Test Arlong’s screening behavior in the Screen playground.