# Provably-Fair Draw Verification

> Provably-Fair Draw Verification is a paid API for AI agents from pyfile-agent.taile3ff35.ts.net, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-13).

Recomputes a provably-fair random draw and verifies that the server seed's SHA-256 hash matches the original commit, confirming the result was not manipulated.

## Facts

- Endpoint: GET https://pyfile-agent.taile3ff35.ts.net/data/fair/verify
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/provably-fair-draw-verification-45a3906e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_96xWH0WunjdQLYmiWYaCA

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 provably-fair-draw-verification-45a3906e
```

Example prompt: Can you verify that round 1 of the draw was fair? The client seed is 'myseed', nonce is 1, and the range was 1 to 100 — I want to confirm the SHA-256 of the server seed actually matches the original commit.

## When to prefer this

Choose this endpoint when you need to cryptographically verify that a previously committed provably-fair random draw was not tampered with, specifically by checking that SHA-256(server_seed) equals the published commit. Ideal for auditing lottery outcomes, game results, or any randomness-dependent decision where integrity must be independently confirmed.

## Known failure modes

- Missing required query parameters (round, client_seed, nonce, min, max) result in a 400 error
- Invalid or mismatched server seed causes verification failure
- min value greater than max value returns an error
- Non-integer values for round, nonce, min, or max may cause parsing errors
- Server-side seed unavailable for the requested round returns a not-found error

## How this service works

Recompute a draw and check sha256(server_seed)==commit. ?round=1&client_seed=s&nonce=1&min=1&max=100

## Output

Returns the recomputed draw result along with the SHA-256 hash of the server seed and a confirmation of whether it matches the original commit, allowing users to independently verify the fairness and integrity of the random draw.

## 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": {}
    }
   }
  },
  "output": {
   "type": "object"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/provably-fair-draw-verification-45a3906e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pyfile-agent.taile3ff35.ts.net](https://www.zero.xyz/host/pyfile-agent.taile3ff35.ts.net/llms.txt)