# SaverVerify Factual Claim Verification

> SaverVerify Factual Claim Verification is a paid API for AI agents from api.saververify.com, paid per call via x402, $0.2/call, status unknown (last checked 2026-10-28).

Independently verifies externally sourced factual claims using live web sources, returning a verdict of supported, contradicted, mixed, or insufficient_evidence with citations.

## Facts

- Endpoint: POST https://api.saververify.com/v2/verify?utm_source=zero.xyz
- Price: $0.2/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/saververify-factual-claim-verification-6ec4b2fe
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sNqR2kvkBYXB_21LuxXW3

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability saververify-factual-claim-verification-6ec4b2fe -d '<json body>'
```

Example prompt: Can you independently verify this claim for me: 'The global electric vehicle market surpassed 10 million units sold in 2022' — I need a cited verdict on whether it's supported, contradicted, or has mixed evidence.

## When to prefer this

Choose this endpoint when an AI agent needs an independent, source-backed second check on a specific factual claim found in external research, third-party data, or agent-generated content — especially before taking action or publishing. Not suited for deterministic arithmetic, wallet risk analysis, transaction simulation, or claims that require proprietary databases rather than open web evidence.

## Known failure modes

- Claim is too vague or ambiguous to evaluate, returning insufficient_evidence
- No live web sources found for the specific claim topic
- Conflicting sources result in a mixed verdict requiring human judgment
- Network or upstream source unavailability delays or fails the verification
- Claim involves real-time or future data not indexed on the web
- Payment of 0.20 USDC on Base not fulfilled, blocking the request

## How this service works

Fact-checking and claim verification API for AI agents. Verify whether a cited source supports a claim; check statistics, dates, units and populations in research reports before publication. Separate web research returns a verdict, linked evidence and sources. Source verification is model-assessed, not guaranteed correct. POST /v2/verify; x402 v2 on Base; 0.20 USDC. No signup or API key.

## Output

Returns a structured verdict — one of: supported, contradicted, mixed, or insufficient_evidence — along with web sources and citations that back the determination. The agent receives both the classification and the evidence trail used to reach it.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/saververify-factual-claim-verification-6ec4b2fe/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.saververify.com](https://www.zero.xyz/host/api.saververify.com/llms.txt)