# Factstamp Statistic Fact-Check

> Factstamp Statistic Fact-Check is a paid API for AI agents from agents.factstamp.dev, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-21).

Checks a dated figure or statistic against its publisher's own series, returning a verdict of verified, stale, contradicted, or unknown with an as-of date — currently covering Australian primary sources.

## Facts

- Endpoint: POST https://agents.factstamp.dev/check?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/factstamp-statistic-fact-check-fe06316f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RawVynG-uGlsqkW847lJj

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 factstamp-statistic-fact-check-fe06316f -d '<json body>'
```

Example prompt: Before I put this in the deck — can you fact-check the figure '6.1% unemployment rate as of March 2024, from the ABS' against the publisher's own series and tell me if it's still verified, stale, or contradicted?

## When to prefer this

Choose this endpoint when you need to validate a specific Australian statistic or dated figure against its publisher's own series before including it in a report, model, presentation, or decision. It is purpose-built for Australian primary sources and returns a machine-readable verdict with provenance. Prefer it over general web search when you need a definitive verified/stale/contradicted classification with an as-of date rather than a list of links.

## Known failure modes

- Statistic outside Australian primary source coverage returns 'unknown' rather than an error
- Ambiguous or unparseable figure description may result in an unknown verdict
- Publisher series not yet indexed returns unknown
- Malformed request body returns HTTP 4xx
- Payment not settled via x402 returns HTTP 402

## How this service works

A fact check on a dated figure or statistic against the publisher's own series: verified, stale, contradicted or unknown, with the as-of date. Relevant wherever a number is going onto a page, deck, model or decision. Coverage today is Australian primary sources; anything outside coverage returns unknown rather than a guess.

## Output

A JSON object containing a verdict (verified, stale, contradicted, or unknown), the as-of date of the checked figure, a reference to the publisher's own series, and any relevant context about why the figure was classified as it was. If the figure falls outside Australian primary source coverage, the verdict is 'unknown' rather than a guess.

## Request schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/factstamp-statistic-fact-check-fe06316f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agents.factstamp.dev](https://www.zero.xyz/host/agents.factstamp.dev/llms.txt)