# FractalAI x402 Notary

> FractalAI x402 Notary is a paid API for AI agents from fractalai.net.co, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-30).

Provides an independent ML-DSA-65 post-quantum attestation of an x402 payment settlement, acting as a cryptographic witness for the transaction.

## Facts

- Endpoint: POST https://fractalai.net.co/api/x402/witness?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fractalai-x402-notary-72001fc0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gVezl6IPR36qFMBEeyFnJ

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 fractalai-x402-notary-72001fc0 -d '<json body>'
```

Example prompt: Can you get an independent ML-DSA-65 notarization of this x402 settlement — POST the JSON body of the completed payment to the FractalAI Notary so we have a post-quantum witness signature on record?

## When to prefer this

Choose this endpoint when you need an independent, post-quantum (ML-DSA-65) third-party notarization of an x402 payment settlement — particularly for audit trails, compliance records, or dispute resolution where a tamper-proof cryptographic witness signature from a separate party is required. Prefer over self-attested records or weaker signature schemes.

## Known failure modes

- Invalid or malformed x402 body returns a validation error
- Missing required fields (type, method, bodyType, body) causes a schema rejection
- Payment failure (insufficient USDC balance) results in a 402 response and no attestation
- Unsupported HTTP method (not POST/PUT/PATCH) causes an enum validation error
- Network timeout if the blockchain layer is unavailable

## How this service works

FractalAI Notary: pay for an independent ML-DSA-65 attestation of an x402 settlement.

## Output

An ML-DSA-65 post-quantum cryptographic attestation (witness/notarization) of the submitted x402 settlement payload, providing an independent third-party signature confirming the transaction occurred.

## 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"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": {
      "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/fractalai-x402-notary-72001fc0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fractalai.net.co](https://www.zero.xyz/host/fractalai.net.co/llms.txt)