x402basequality 0.45

Send a USDC tip ("buy a coffee") via x402 payment on Base network.

Price
1.00 USDC / call
Protocol
x402
Verified
no
Endpoint
https://x402-poc.vercel.app/api/0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0/coffee

What it does

This x402 endpoint implements a simple tipping mechanism — "buy someone a coffee" — using the x402 payment protocol on the Base network. When an unauthenticated GET request is made, the endpoint returns a 402 Payment Required challenge specifying that 1 USDC (1,000,000 units in 6-decimal USDC) must be sent to the wallet address 0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0 via the "exact" payment scheme. The accepted asset is USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base.

The hosting application at x402-poc.vercel.app is a proof-of-concept that lets users create their own x402 tip links. The landing page shows a simple "Create your x402 tip link" interface. There is no additional documentation, pricing page, or OpenAPI spec available — the 402 challenge itself is the primary specification for interacting with this endpoint.

To complete a payment, a caller must include an X-PAYMENT header conforming to x402 version 1 with the exact amount. The payment timeout is 300 seconds. Upon successful payment, the endpoint returns an application/json response. Because this is a proof-of-concept, there is no information about rate limits, SLAs, or the structure of the success response beyond the MIME type.

Capabilities

x402-paymentusdc-tippingbase-networkexact-payment-schemecrypto-micropayment

Use cases

  • —Sending a USDC tip to a specific wallet address via an HTTP request
  • —Demonstrating x402 protocol payment flows in agent or app integrations
  • —Creating a pay-per-access gate for content or services using x402

Fit

Best for

  • —Developers experimenting with the x402 payment protocol
  • —Agents that need to make small USDC payments programmatically
  • —Users who want a simple crypto tipping endpoint on Base

Not for

  • —Production payment processing requiring SLAs and guarantees
  • —Non-crypto or fiat-based tipping workflows
  • —High-value transactions (this is a 1 USDC PoC tip)

Quick start

curl -i https://x402-poc.vercel.app/api/0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0/coffee
# Returns 402 with x402 challenge. Include X-PAYMENT header with valid payment to complete.

Example

Response

{
  "error": "X-PAYMENT header is required",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0",
      "scheme": "exact",
      "network": "base",
      "mimeType": "application/json",
      "resource": "https://x402-poc.vercel.app/api/0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0/coffee",
      "description": "buy 0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0 a coffee.",
      "maxAmountRequired": "1000000",
      "maxTimeoutSeconds": 300
    }
  ],
  "x402Version": 1
}

Endpoint

URLhttps://x402-poc.vercel.app/api/0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0/coffee
Transporthttp
Protocolx402
Pay to0xb81F6a3dE77c5192aA08Ed3F0376159e72412bF0
CurrencyUSD COIN

Quality

0.45/ 1.00

The endpoint is live and returns a well-formed x402 challenge with clear payment parameters. However, this is a proof-of-concept with no documentation, no OpenAPI spec, no success response examples, and no information about what is returned after payment. The description and title are minimal and auto-generated.

Warnings

  • —Proof-of-concept deployment — no SLA, documentation, or guarantees
  • —No docs, OpenAPI spec, or pricing page available (all return 404)
  • —Success response schema is unknown; only MIME type application/json is specified
  • —Wallet address in URL is user-specific — this is one instance of a generic tip-link generator

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-18 19:35:57Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-24

Agent access

JSONhttps://clawmart.sh/api/listings/bYg7q6
Send a USDC tip ("buy a coffee") via x402 payment on Base network. — Clawmart · Clawmart