# SkillfulAI X402 Demo Premium Endpoint (Mainnet)

> SkillfulAI X402 Demo Premium Endpoint (Mainnet) is a paid API for AI agents from api-dev.agents.skillfulai.io, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-18).

Accepts a $0.01 USDC micropayment on Base mainnet via the X402 protocol and returns a premium-tier welcome message with payment verification details.

## Facts

- Endpoint: POST https://api-dev.agents.skillfulai.io/api/x402/demo/mainnet/premium?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-dev-agents-skillfulai-io-77e755a3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CPSH_8nha6FjrorTFhPfY

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 api-dev-agents-skillfulai-io-77e755a3 -d '<json body>'
```

Example prompt: Run the SkillfulAI premium demo on mainnet — pay the $0.01 USDC fee from my wallet and show me the payment confirmation including the transaction hash and whether settlement was verified.

## When to prefer this

Use this endpoint when you need to demonstrate or test the X402 pay-per-call protocol on Base mainnet with real USDC. Ideal for verifying that an AI agent can autonomously handle micropayment-gated APIs, or for integration testing of X402 payment flows before building production pay-per-call services. Not suitable for retrieving actual business data — this is a demo/test endpoint.

## Known failure modes

- Payment not included or malformed X402 header → 402 Payment Required with accepted payment schemes
- Insufficient USDC balance in wallet → payment failure before request reaches endpoint
- Wrong network (non-Base mainnet) → payment rejected or unverified
- Incorrect asset address (non-USDC) → payment not accepted
- Transaction not yet confirmed on-chain → settled: false, verified: false
- Endpoint temporarily unavailable → 5xx error

## How this service works

Demo X402 premium endpoint (mainnet) - pay $0.01 USDC

## Output

Returns a JSON object with: a 'premium' tier enum confirming access level, a welcome message string for premium users, and a payment object containing the payer wallet address, network name, settlement boolean, verification boolean, amount paid in atomic units, and the on-chain transaction hash.

## Example request

```json
{
 "asset": "USDC",
 "network": "base-mainnet",
 "paymentAmount": "0.01",
 "recipientEmail": "zero-qa@agentmail.to",
 "notifyOnCompletion": true
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "message",
  "tier",
  "payment"
 ],
 "properties": {
  "tier": {
   "enum": [
    "premium"
   ],
   "type": "string",
   "description": "Access tier level"
  },
  "message": {
   "type": "string",
   "description": "Welcome message for premium users"
  },
  "payment": {
   "type": "object",
   "properties": {
    "payer": {
     "type": "string",
     "description": "Payer wallet address"
    },
    "network": {
     "type": "string",
     "description": "Payment network"
    },
    "settled": {
     "type": "boolean"
    },
    "verified": {
     "type": "boolean"
    },
    "amount_paid": {
     "type": "string",
     "description": "Amount paid in atomic units"
    },
    "transaction_hash": {
     "type": "string",
     "description": "On-chain transaction hash"
    }
   },
   "description": "Payment verification and settlement details"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-dev-agents-skillfulai-io-77e755a3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api-dev.agents.skillfulai.io](https://www.zero.xyz/host/api-dev.agents.skillfulai.io/llms.txt)