x402basequality 0.35

Portfolio performance data via x402 micropayment on Base network, $0.02/request in USDC.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/portfolios/39/performance

What it does

This endpoint at lowpaymentfee.com provides portfolio performance data for a specific portfolio (ID 39) behind an x402 paywall. The endpoint 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 broad catalog of x402-gated APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request. This particular endpoint falls under the finance category and appears to return performance metrics for a tracked portfolio. No API keys or rate limits are advertised; access is granted purely via the x402 payment header.

Documentation is extremely sparse. The docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what fields the portfolio performance response contains. The endpoint is confirmed live (returns a proper 402 challenge), but the lack of documentation means callers must discover the response format experimentally.

Capabilities

x402-paymentusdc-base-networkportfolio-performancejson-apimicropaymentno-api-keypay-per-request

Use cases

  • —Retrieving performance metrics for a tracked investment portfolio
  • —Integrating portfolio performance data into dashboards or agent workflows
  • —Paying per-request for financial data without subscription commitments

Fit

Best for

  • —Agents or apps needing on-demand portfolio performance data without API key management
  • —Developers experimenting with x402 micropayment protocols on Base
  • —Low-volume consumers who prefer pay-per-call over subscriptions

Not for

  • —Users needing detailed API documentation or response schema before integrating
  • —High-frequency trading systems requiring sub-second latency guarantees
  • —Anyone without a Base-network USDC wallet

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/portfolios/39/performance \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-token>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/portfolios/39/performance
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is confirmed live with a valid x402 402 challenge, but documentation is essentially nonexistent — no OpenAPI spec, no request/response examples, no field descriptions. The portfolio endpoint path and pricing are clear, but everything else must be discovered experimentally.

Warnings

  • —No API documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content
  • —No OpenAPI or schema describing request parameters or response fields for this endpoint
  • —The specific portfolio ID (39) is hardcoded in the path; it is unclear whether other portfolio IDs are available or what they represent
  • —Response format and fields are completely unknown

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 08:36:33Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-27

Agent access

JSONhttps://clawmart.sh/api/listings/ctx2v9
Portfolio performance data via x402 micropayment on Base network, $0.02/request in USDC. — Clawmart · Clawmart