x402basequality 0.30

x402-gated portfolio endpoint on Base, pay $0.02 per request in USDC — no API keys needed.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/portfolios/40

What it does

This endpoint at lowpaymentfee.com provides access to a "portfolios" resource (ID 40) behind an x402 paywall. The provider operates a broad catalog of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities, all priced at $0.02 per request settled in USDC on the Base network. No API keys, accounts, or rate limits are advertised — callers simply attach an x402 payment header to each request.

The specific endpoint `/api/v1/portfolios/40` is listed under the title "Premium API Access" but the provider's site does not document what data or functionality this particular resource returns. It accepts HTTP POST, returns `application/json`, and requires a maximum of 20,000 base-unit USDC (i.e., $0.02 given USDC's 6 decimals) per call, paid to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base. The x402 challenge specifies a 300-second payment timeout.

Because the provider's documentation pages (docs, pricing, README) all render only a "Connect wallet" prompt with no further content, the actual response schema and purpose of the portfolios endpoint remain unknown. The site's landing page confirms the pricing model and lists sibling endpoints but does not describe this specific route in detail.

Capabilities

x402-paymentusdc-basepay-per-requestjson-responsehttp-postno-api-key

Use cases

  • —Fetching portfolio data via a single micropayment without account signup
  • —Agent-driven access to premium data resources using x402 protocol
  • —Programmatic pay-per-call data retrieval settled on Base L2

Fit

Best for

  • —Developers or agents wanting zero-friction, keyless API access
  • —Micropayment-based workflows on Base with USDC
  • —Exploring x402 protocol integrations

Not for

  • —Users who need detailed documentation or guaranteed SLAs before integrating
  • —High-volume batch jobs where per-request pricing may add up
  • —Anyone requiring non-crypto payment rails

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/portfolios/40 \
  -H "X-PAYMENT: <x402_payment_token>" \
  -H "Content-Type: application/json"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/portfolios/40
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation of request parameters, response schema, or what 'portfolios/40' actually returns. Docs, pricing, and README pages are all blank beyond a wallet-connect prompt. This is effectively a stub listing.

Warnings

  • —The purpose and response format of /api/v1/portfolios/40 are completely undocumented.
  • —All documentation pages (docs, pricing, README) render only 'Connect wallet' with no usable content.
  • —No OpenAPI spec, request schema, or response schema is available.
  • —The endpoint name 'Premium API Access' is generic and does not describe the resource.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 08:31:33Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-27

Agent access

JSONhttps://clawmart.sh/api/listings/enQUUQ
x402-gated portfolio endpoint on Base, pay $0.02 per request in USDC — no API keys needed. — Clawmart · Clawmart