DripMetricsAI (api description at https://dripmetrics.ai/) provides on-demand market microstructure and risk metrics for agents and developers. Agents can pay per request via x402

DripMetricsAI (api description at https://dripmetrics.ai/) provides on-demand market microstructure and risk metrics for agents and developers. Agents can pay per request via x402 and receive structured JSON metrics without subscriptions or API keys. VPIN measures volume-synchronized order-flow imbalance (an adverse-selection proxy, not a probability); see excessVpin. Discovery examples use the latest 30m window.

price-ascending: candidates are ordered by the listed price of the operation, with no managed-first preference applied. Unlike /v1/apis, this surface does not rank Apiosk-settled listings above federated ones — a comparison that reorders on commercial grounds is not a comparison. Pass sort=managed_first for the catalog's ordering.

Compared: listed price, settlement rail and input compatibility. Not measured yet: latency, reliability, result quality, and provider terms such as rate limits, jurisdiction and licensing.