Retrieve email attachments via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com provides access to email attachments (specifically email ID 62) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled in USDC on the Base network at $0.02 per call (maxAmountRequired of 20,000 base units with 6 decimals = $0.02), with no API keys, rate limits, or subscriptions required.
The broader lowpaymentfee.com platform advertises a suite of x402-gated APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance and crypto data feeds, and infrastructure utilities — all priced at $0.02 per request. However, this specific endpoint (/api/v1/emails/62/attachments) is not listed on the provider's landing page among the advertised API categories. Its purpose — retrieving attachments for a specific email — is unclear in context, and no documentation, request schema, or response schema is available beyond the x402 challenge itself.
The endpoint is live and returns a valid x402 challenge (HTTP 402 with version 1 accepts block). The payment address is 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 and the USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base. Timeout is 300 seconds. No OpenAPI spec, ai-plugin manifest, or detailed docs were found during crawl — the docs, pricing, API, and README pages all returned only a "Connect wallet" prompt with no substantive content.
Capabilities
Use cases
- —Retrieving email attachments programmatically via micropayment
- —Agent-driven email data access without API keys
- —Pay-per-request email attachment download
Fit
Best for
- —Agents needing one-off email attachment retrieval without subscriptions
- —Developers experimenting with x402 micropayment protocols
- —Workflows requiring keyless, pay-per-call email data access
Not for
- —Bulk email processing or high-volume attachment downloads (no documented batch support)
- —Users who need detailed API documentation or guaranteed SLAs
- —Accessing emails other than ID 62 (endpoint is hardcoded to a single email)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/62/attachments \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no request/response schema, and the specific endpoint (/emails/62/attachments) is not listed among the provider's advertised APIs. The crawled docs/pricing/API pages contained no usable content. The purpose and utility of this particular endpoint are unclear.
Warnings
- —This endpoint (/api/v1/emails/62/attachments) is not listed among the provider's advertised API categories — it may be a test or internal endpoint.
- —No request body schema or response schema is documented anywhere.
- —All documentation pages (docs, pricing, API, README) returned only 'Connect wallet' with no substantive content.
- —The endpoint is hardcoded to email ID 62; it is unclear whether other email IDs are supported or what data is returned.
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 in USDC on Basehttps://lowpaymentfee.com/api/v1/emails/62/attachments
- —The platform advertises all APIs at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/emails/62/attachments
- —Docs, pricing, API, and README pages returned only 'Connect wallet' with no documentation contenthttps://lowpaymentfee.com/docs