Static x402 test endpoint returning a text message for a $0.001 USDC micropayment on Base.
What it does
This is a simple x402-gated endpoint hosted on Cloudflare Workers that returns a static text response upon receiving a valid micropayment. It is part of a small API by artlu that also gates blog post content behind x402 payments. The `/paid` endpoint specifically serves as a static testing endpoint, useful for verifying x402 payment flows and agent integration without significant cost.
The endpoint accepts POST requests and requires an `X-PAYMENT` header conforming to the x402 protocol (version 1, "exact" scheme). Payment is made in USDC on the Base network, with a maximum amount of $0.001 (1000 units in the asset's smallest denomination). On successful payment, the endpoint returns a `text/plain` response containing a message string. The output schema indicates the message value is redacted in the challenge (shown as "****"), consistent with it being gated content.
The source code is open-source under the MIT license and available on GitHub. There is no OpenAPI spec, no dedicated docs page, and no additional endpoints beyond the home page, a health check, this static test endpoint, and one gated blog post endpoint. This is a minimal, developer-oriented testing tool rather than a production content service.
Capabilities
Use cases
- —Testing x402 payment flow integration in agent or client code
- —Verifying USDC micropayment handling on the Base network
- —Smoke-testing x402-compatible wallets or libraries against a cheap live endpoint
Fit
Best for
- —Developers building x402-compatible agents or clients
- —Quick validation of micropayment plumbing at negligible cost ($0.001)
- —Learning how the x402 protocol challenge-response cycle works
Not for
- —Production content delivery or meaningful data retrieval
- —High-throughput or latency-sensitive workloads (no SLA or performance guarantees)
- —Users needing rich structured data responses
Quick start
curl -X POST https://x402.artlu.workers.dev/paid \
-H "X-PAYMENT: <your-x402-payment-header>"Example
Response
{
"message": "****"
}Endpoint
Quality
The endpoint is live and returns a valid 402 challenge with an outputSchema, but documentation is minimal (no OpenAPI spec, no docs page, no usage examples). The endpoint is explicitly described as a static testing tool, and the response content is trivial.
Warnings
- —No OpenAPI or dedicated documentation available; /docs returns 404.
- —This is a static test endpoint returning a fixed message — not a production content API.
- —Output schema example value is redacted ("****"); actual response content is unknown without payment.
Citations
- —The /paid endpoint is described as a 'static endpoint for testing ($0.001)'https://x402.artlu.workers.dev
- —The API also gates blog posts behind x402 payments, e.g. /gated/the-forever-spreadsheet for $1.00https://x402.artlu.workers.dev
- —Source code is MIT-licensed and available on GitHubhttps://github.com/artlu99/x402-blogposts-gate
- —Payment is in USDC on Base network with maxAmountRequired of 1000 (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)https://x402.artlu.workers.dev/paid