Retrieve email attachments via x402 micropayment on Base (USDC, $0.02/request).
What it does
This endpoint at lowpaymentfee.com provides access to email attachments (specifically email ID 89) behind an x402 paywall. It accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 20,000 base units, which equals $0.02 per request (USDC uses 6 decimals).
The provider lowpaymentfee.com hosts a broader suite of x402-gated APIs spanning data & analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are advertised at $0.02 per request with no API keys, no rate limits, and no minimum commitments.
This specific endpoint (/api/v1/emails/89/attachments) appears to serve attachment data for a particular email resource. No OpenAPI schema, request body documentation, or response examples were found in the crawl. The docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. The endpoint is confirmed live via a valid 402 challenge.
Capabilities
Use cases
- —Programmatically retrieving email attachments with per-request micropayments
- —Agent-driven workflows that need to fetch specific email attachment data
- —Integrating email attachment retrieval into automated pipelines without API key management
Fit
Best for
- —Agents needing on-demand email attachment access without subscription
- —Workflows requiring pay-per-use access to specific email data
- —Developers testing x402 micropayment integrations on Base
Not for
- —Bulk email processing or high-volume attachment downloads (no documented batch support)
- —Users who need detailed API documentation or response schemas before integrating
- —Accessing arbitrary emails — this endpoint is scoped to email ID 89
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/emails/89/attachments \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and network. However, there is no OpenAPI schema, no request/response documentation, no examples, and the docs pages are empty stubs. The endpoint is narrowly scoped to a single email ID with no explanation of what it returns or how to use it.
Warnings
- —No API documentation available — docs, pricing, and README pages all return only 'Connect wallet' with no content
- —Endpoint is hardcoded to email ID 89; unclear if other email IDs are accessible or what the attachment data contains
- —No request body schema or response schema documented
- —No OpenAPI or ai-plugin manifest found
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/emails/89/attachments
- —All endpoints on lowpaymentfee.com are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/emails/89/attachments