# web-attestation.selfradiance.workers.dev Web Attestation

> web-attestation.selfradiance.workers.dev Web Attestation is a paid API for AI agents from web-attestation.selfradiance.workers.dev, paid per call via x402, $1/call, status unknown (last checked 2026-10-11).

Returns an Ed25519-signed cryptographic attestation of the raw byte response observed at a caller-supplied HTTPS URL, without making any claims about content truth or legitimacy.

## Facts

- Endpoint: GET https://web-attestation.selfradiance.workers.dev/attest?utm_source=zero.xyz
- Price: $1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/web-attestation-selfradiance-workers-dev-web-attestation-91080cfe
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qauvmt-0nQdma2HPdcjJf

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 web-attestation-selfradiance-workers-dev-web-attestation-91080cfe
```

Example prompt: Can you get me a cryptographically signed Ed25519 attestation witnessing exactly what bytes https://api.example.com/data returns right now — I need the SHA-256 hash, HTTP status, and the signed payload as proof?

## When to prefer this

Use this endpoint when you need a lightweight, cryptographically verifiable byte-level witness receipt for an HTTPS URL's current response — particularly useful for audit trails, dispute resolution, or proving to third parties what a URL returned at a specific moment. Prefer this over a simple web scraper when tamper-evidence and a signed timestamp matter. Not suitable if you need content interpretation, truth verification, or structured data extraction.

## Known failure modes

- Target URL is not reachable or returns a network error — attestation cannot be produced
- Target URL is HTTP (not HTTPS) — only HTTPS URLs are supported
- URL returns a redirect — redirect_policy is manual_no_follow so no redirect is followed, response reflects the redirect itself
- Response body exceeds 1 MB — body is truncated and truncated flag is set to true
- Payment of 1 USDC not provided via x402 — returns 402 Payment Required
- Invalid or malformed URL input — returns error response

## How this service works

Returns an Ed25519-signed witness-only byte-observation attestation for a caller-supplied HTTPS URL.

## Output

A JSON object containing: a base64 or hex Ed25519 signature, a structured payload with the attestation type, a key ID (kid), a unique attestation ID, the observed timestamp, the canonicalized request details (method, URL, redirect policy), response metadata (HTTP status, ok flag, content-type), and a SHA-256 hash of the response body bytes (with truncation info if body exceeded 1 MB). Includes a human_notice clarifying this is a byte-observation receipt only with no truth claims.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {
   "url": "https://www.example.com"
  }
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "payload",
      "signature",
      "kid"
     ],
     "properties": {
      "kid": {
       "type": "string"
      },
      "payload": {
       "type": "object",
       "required": [
        "attestation_type",
        "kid",
        "attestation_id",
        "observed_at",
        "canonicalization",
        "request",
        "response",
        "body",
        "claims",
        "human_notice"
       ],
       "properties": {
        "kid": {
         "type": "string"
        },
        "body": {
         "type": "object",
         "required": [
          "hash_alg",
          "sha256_hex",
          "hash_subject",
          "bytes_hashed",
          "complete_body_observed",
          "truncated",
          "max_bytes"
         ],
         "properties": {
          "hash_alg": {
           "type": "string",
           "const": "sha-256"
          },
          "max_bytes": {
           "type": "number",
           "const": 1048576
          },
          "truncated": {
           "type": "boolean"
          },
          "sha256_hex": {
           "type": "string",
           "pattern": "^[0-9a-f]{64}$"
          },
          "bytes_hashed": {
           "type": "number"
          },
          "hash_subject": {
           "type": "string",
           "const": "response_body_bytes"
          },
          "complete_body_observed": {
           "type": "boolean"
          }
         },
         "additionalProperties": false
        },
        "claims": {
         "type": "string",
         "const": "none"
        },
        "request": {
         "type": "object",
         "required": [
          "method",
          "url",
          "redirect_policy"
         ],
         "properties": {
          "url": {
           "type": "string"
          },
          "method": {
           "type": 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/web-attestation-selfradiance-workers-dev-web-attestation-91080cfe/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from web-attestation.selfradiance.workers.dev](https://www.zero.xyz/host/web-attestation.selfradiance.workers.dev/llms.txt)