x402-gated portfolio data endpoint on Base, pay $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a specific portfolio resource (portfolio ID 34) via the x402 payment protocol. The endpoint is live and returns a standard x402 challenge requiring payment of 20,000 base units of USDC on the Base network, which equals $0.02 per request (USDC uses 6 decimals). Payment is made via the "exact" scheme to the specified wallet address, with no API keys or rate limits required.
The broader lowpaymentfee.com platform hosts a variety of pay-per-call API endpoints spanning data & analytics, AI & machine learning (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are uniformly priced at $0.02 per request and settle on the Base network using USDC.
Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what the portfolio endpoint actually returns. The endpoint accepts POST requests and serves application/json, but the exact input parameters and output format are unknown.
Capabilities
Use cases
- —Retrieving portfolio data without needing API key registration
- —Programmatic access to portfolio information via micropayment
- —Agent-driven data retrieval with per-call USDC settlement on Base
Fit
Best for
- —Developers wanting zero-signup API access via crypto micropayments
- —AI agents that can settle x402 payments autonomously
- —Users who prefer pay-per-use pricing with no commitments
Not for
- —Users who need detailed API documentation or schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/34 \
-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 OpenAPI schema, no request/response examples, and no description of what portfolio data is actually returned. The docs pages are empty beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — input parameters and response format are completely unknown
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no useful content
- —The specific purpose and data returned by /api/v1/portfolios/34 is undocumented
- —No example requests or responses available to verify endpoint behavior
Citations
- —Endpoint returns x402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/34
- —All endpoints priced 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: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/34