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x402 Alert Username Check API
x402
x402 Alert Username Check API is a paid API for AI agents from x402-alert.vercel.app, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).
Checks the availability or validity of a username, paid via USDC on Base using the x402 protocol
Price / call$0.05
Success—
StatusUnknown
How this service works
14 paid financial API endpoints. Pay with USDC on Base using x402 protocol.
Output
Returns a result object containing data about the username check, such as whether the username is available, taken, or valid, along with any relevant metadata returned by the API.
Example use cases
Verify username availability for crypto app
“I'm building a crypto trading bot and need to check if 'TradeBot_v3' is available as a username. Can you verify that using x402 Alert and go ahead with the USDC payment?”
Validate social handle before registration
“Before I sign up for this new Web3 platform, can you quickly check if my desired username 'DeFi_Maven' is taken? I'm fine paying the small fee through x402.”
Check multiple usernames for brand consistency
“I'm setting up accounts across several DeFi protocols. Can you check if these usernames are available: 'LiquidityPool_Co', 'LPc_Official', and 'LP_Collective'? Use x402 to verify them and charge my USDC balance.”
Technical details
Endpoint
POSThttps://x402-alert.vercel.app/api/username-checkWhen to prefer
Use this endpoint when you need to programmatically verify whether a specific username is available or valid and are comfortable paying micro-transactions in USDC on the Base network via the x402 protocol. Prefer this over free alternatives when integrating with the x402 Alert financial monitoring ecosystem.
Side effects
- Missing or invalid username input returns an error
- Insufficient USDC balance for x402 payment causes payment failure
- Network error on Base blockchain during payment processing
- Malformed request body results in 400 Bad Request
- Username field empty or null causes validation error
Output
Schema · Response
| Field | Type | Description |
|---|---|---|
| result | object | API response data |
Tags
x402
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