# MCX Ventures Adversarial Verification — Standard Tier

> MCX Ventures Adversarial Verification — Standard Tier is a paid API for AI agents from api.mcx-ventures.com, paid per call via x402, $1.5/call, status unknown (last checked 2026-09-15).

Runs a two-stage adversarial verification (Skeptic critic + Verifier) on a submitted text payload to stress-test and validate its claims or content.

## Facts

- Endpoint: POST https://api.mcx-ventures.com/v2/verify/standard
- Price: $1.5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mcx-ventures-adversarial-verification-standard-tier-9276ce15
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-JrajifrOoSlvMJBPAfqt

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 mcx-ventures-adversarial-verification-standard-tier-9276ce15 -d '<json body>'
```

Example prompt: Run the standard adversarial verification on this paragraph — put it through the Skeptic and Verifier: 'Our product reduces churn by 40% based on internal benchmarks from Q3 2024 across 200 enterprise customers.'

## When to prefer this

Choose this standard-tier endpoint over the basic tier when you need both a Skeptic critique AND a Verifier follow-up — i.e., when you want adversarial stress-testing plus a second-pass assessment of the critique itself, not just a single-pass skeptical read. Prefer this over general-purpose LLM fact-checking when you need a structured, reproducible two-stage adversarial pipeline with a consistent API contract.

## Known failure modes

- Missing or empty 'payload' field returns a 400 validation error
- Payment not included or insufficient USDC triggers a 402 Payment Required response
- Submitting a non-string payload type may cause schema rejection
- Overly large payloads may exceed processing limits and return a 413 or timeout
- Malformed JSON body results in a 400 parse error

## How this service works

Adversarial verification, standard tier — Skeptic + Verifier

## Output

Returns a structured adversarial analysis containing a Skeptic-stage critique identifying weaknesses, contradictions, or unsupported claims in the submitted payload, followed by a Verifier-stage assessment that evaluates or rebuts the skeptic's challenges — giving the caller a two-perspective stress-test of the content's validity.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "payload"
     ],
     "properties": {
      "payload": {
       "type": "string",
       "description": "Content to verify. Required on the paid POST."
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mcx-ventures-adversarial-verification-standard-tier-9276ce15/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.mcx-ventures.com](https://www.zero.xyz/host/api.mcx-ventures.com/llms.txt)