# Second Opinion — Live Web Verification

> Second Opinion — Live Web Verification is a paid API for AI agents from secondopinionx402.com, paid per call via x402, $0.2/call, status unknown (last checked 2026-09-14).

Sends a claim to an independent adversarial agent that actively researches the web to attempt to refute it, then returns a structured verdict with citations.

## Facts

- Endpoint: POST https://secondopinionx402.com/v1/verify
- Price: $0.2/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/second-opinion-live-web-verification-48b2817e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_7_mKPX9opq2i9ZxPukZHk

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 second-opinion-live-web-verification-48b2817e -d '<json body>'
```

Example prompt: Can you do a live web fact-check on the claim that 'the Eiffel Tower is the tallest structure in France' — run an adversarial check with real internet research and give me a structured verdict with citations?

## When to prefer this

Choose this endpoint when you need an adversarial, citation-backed fact-check grounded in live web research — not just logical reasoning. It is superior to the 'quick' sibling endpoint when you need real-world evidence and citations rather than pure logical analysis. Prefer this over the 'panel' endpoint when you want a single, focused adversarial verdict rather than three distinct lens-based attacks. Ideal for journalism, due diligence, misinformation detection, or any scenario where current web evidence matters.

## Known failure modes

- Claim is too vague or ambiguous for the agent to research effectively
- Live web research returns insufficient or conflicting sources, resulting in an inconclusive verdict
- Payment of $0.20 USDC not settled via x402 protocol, causing authentication failure
- Request body is malformed or missing the required claim input, returning a 400-level error
- Web sources found are outdated or unreliable, reducing verdict quality
- Rate limiting or timeout if the web research phase exceeds allowable duration

## How this service works

Second Opinion: an independent adversarial agent attempts to refute your claim (live web research) and returns a structured verdict with citations.

## Output

A structured verdict object indicating whether the claim was refuted or supported, along with cited web sources used in the adversarial research, confidence signals, and reasoning from the independent skeptical agent.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "bodyType",
    "body",
    "method"
   ],
   "properties": {
    "body": {
     "properties": {}
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/second-opinion-live-web-verification-48b2817e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from secondopinionx402.com](https://www.zero.xyz/host/secondopinionx402.com/llms.txt)