AI agent redirected here. Catalog pages (/category, /tag, /page) do not return full HTML without payment. Use this documentation, llms.txt, and pricing.json first.

🔐 x402 Payment Protocol Documentation

Welcome to Free3D.io's AI-friendly API. We support AI agents and bots, but require payment for access to our content catalog. Payments are accepted exclusively via the open x402 protocol (USDC / PYUSD on Base or Ethereum) or via a persistent API key.

💰 Pricing Plans

Plan Price Rate Limit Best For
Pay Per Request $1.00 per request (USDC / PYUSD) No limit One-time access, testing
Basic API Key $50/month 100/hour, 1,000/day Small AI agents
Pro API Key $200/month 1,000/hour, 20,000/day Production agents
Enterprise Custom 10,000/hour, 500,000/day Large-scale training

🚀 Quick Start

When your bot accesses our site without a valid payment header, you receive a spec-compliant response:

HTTP/1.1 402 Payment Required
Content-Type: application/json
PAYMENT-REQUIRED: <base64-encoded PaymentRequired JSON>

{
  "x402Version": 2,
  "error": "PAYMENT-SIGNATURE header is required",
  "resource": { "url": "https://free3d.io/...", "mimeType": "application/json" },
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:8453",
      "amount": "1000000",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "payTo": "0x...",
      "maxTimeoutSeconds": 300,
      "extra": { "name": "USDC", "version": "2" }
    }
  ]
}

📋 Payment Methods

Method 1 — API Key (recommended for production)

Purchase a monthly subscription and use your API key for all requests.

curl -H "X-API-Key: x402_your_api_key_here" https://free3d.io/

Contact: free3dio@pm.me — to purchase API keys (paid in USDC/PYUSD).

Method 2 — x402 v2 (gasless, EIP-3009)

Sign an EIP-3009 TransferWithAuthorization off-chain and send it in the PAYMENT-SIGNATURE header. No gas paid by the client.

import base64, json, secrets, time, requests
from eth_account import Account
from eth_account.messages import encode_typed_data

# 1. Read payment requirements from PAYMENT-REQUIRED header (or response body).
r = requests.get("https://free3d.io/")
pr = json.loads(base64.b64decode(r.headers["PAYMENT-REQUIRED"]))
chosen = pr["accepts"][0]   # e.g. Base USDC

# 2. Build EIP-3009 authorization.
auth = {
    "from":        "0xYourWallet",
    "to":          chosen["payTo"],
    "value":       chosen["amount"],
    "validAfter":  int(time.time()),
    "validBefore": int(time.time()) + chosen["maxTimeoutSeconds"],
    "nonce":       "0x" + secrets.token_hex(32),
}

# 3. Sign EIP-712 (TransferWithAuthorization).
typed = {
    "types": {
        "EIP712Domain": [
            {"name": "name",              "type": "string"},
            {"name": "version",           "type": "string"},
            {"name": "chainId",           "type": "uint256"},
            {"name": "verifyingContract", "type": "address"},
        ],
        "TransferWithAuthorization": [
            {"name": "from",        "type": "address"},
            {"name": "to",          "type": "address"},
            {"name": "value",       "type": "uint256"},
            {"name": "validAfter",  "type": "uint256"},
            {"name": "validBefore", "type": "uint256"},
            {"name": "nonce",       "type": "bytes32"},
        ],
    },
    "primaryType": "TransferWithAuthorization",
    "domain": {
        "name":              chosen["extra"]["name"],
        "version":           chosen["extra"]["version"],
        "chainId":           int(chosen["network"].split(":")[1]),
        "verifyingContract": chosen["asset"],
    },
    "message": auth,
}
signed = Account.sign_typed_data(full_message=typed, private_key="0xYourPrivKey")

# 4. Build PaymentPayload (x402 v2 §5.2) and send.
payload = {
    "x402Version": 2,
    "resource":    pr["resource"],
    "accepted":    chosen,
    "payload": {
        "signature":     signed.signature.hex(),
        "authorization": auth,
    },
}
headers = {
    "PAYMENT-SIGNATURE": base64.b64encode(json.dumps(payload).encode()).decode()
}
print(requests.get("https://free3d.io/", headers=headers).status_code)

Method 3 — Legacy x402 (post-settlement)

Send 1 USDC/USDT/PYUSD to the wallet listed in accepts[i].payTo, then either retry the request with the transaction hash, or exchange it for a one-time access token.

# Direct retry with header:
curl -H "X-Payment: 0xYourTxHash:base" https://free3d.io/

# Two-step: verify on-chain, then use one-time access token (15 min):
curl -X POST https://free3d.io/x402/verify \
     -H "Content-Type: application/json" \
     -d '{"tx_hash":"0xYourTxHash","network":"base","resource_id":"/"}'
# → {"access_token":"uuid-token"}

curl -H "X-Access-Token: uuid-token" https://free3d.io/

🔧 Integration Examples

Python (requests)

import requests

# With API key:
headers = {"X-API-Key": "x402_your_key"}
r = requests.get("https://free3d.io/", headers=headers)

if r.status_code == 200:
    print("Access granted!")
elif r.status_code == 402:
    print("Payment required:", r.json())
elif r.status_code == 429:
    print("Rate limit exceeded")

JavaScript (Node.js)

const axios = require('axios');

async function accessWithApiKey() {
  try {
    const r = await axios.get('https://free3d.io/', {
      headers: { 'X-API-Key': 'x402_your_key' },
    });
    console.log('Access granted!', r.data);
  } catch (err) {
    if (err.response?.status === 402) {
      console.log('Payment required:', err.response.data);
    } else if (err.response?.status === 429) {
      console.log('Rate limit exceeded');
    }
  }
}

cURL

curl -H "X-API-Key: x402_your_key" https://free3d.io/
curl -H "X-API-Key: x402_your_key" https://free3d.io/model/chair/abc123?a=download&do=get

📊 Response Codes

CodeMeaningAction
200SuccessAccess granted
402 (preferred) or 401Payment RequiredDecode PAYMENT-REQUIRED (base64 JSON) or read the JSON body; check X-X402-Status: payment_required
429Rate Limit ExceededWait or upgrade plan
401Invalid API Key (non-AI clients)Renew or replace your API key

📈 Monitoring & Analytics

Successful payments (402 → 200) are logged to logs/x402_conversions.log:

[2026-05-07 10:31:00] CONVERSION_200 | method: api_key  | resource: /                | id: x402_key_123  | IP: 1.2.3.4 | UA: CustomAgent/1.0
[2026-05-07 10:32:00] CONVERSION_200 | method: eip3009  | resource: /                | id: eip3009_signature | IP: 1.2.3.4 | UA: x402-fetch/0.4
[2026-05-07 10:33:00] CONVERSION_200 | method: legacy   | resource: /tag/character   | id: 0xabc...:base | IP: 1.2.3.4 | UA: ChatGPT-User/1.0
[2026-05-07 10:34:00] CONVERSION_200 | method: token    | resource: /                | id: uuid-token    | IP: 1.2.3.4 | UA: ClaudeBot/1.0

Methods tracked: api_key, eip3009, legacy, token.

Errors are logged to logs/x402.log.

⚠️ Important Notes

🤝 Getting Started

  1. For testing: Use pay-per-request via x402 v2 (any USDC wallet supporting EIP-3009).
  2. For production: Email free3dio@pm.me to purchase a persistent API key.
  3. For enterprise: Custom pricing and SLA available.

📞 Support

Questions: free3dio@pm.me

Machine-readable pricing: /x402/pricing.json

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