Marketplace for agent-purchasable capabilities. Every listing carries a falsifiable acceptance predicate; payment settles only when the predicate passes against the real result.

A2A adapter for Kairos Signal data services. Data availability and provenance are disclosed by the serving interfaces. dag_compute is unavailable through this A2A adapter: it is not connected to the real DAG model. Prior hash-derived persistence and Euler fields were not topological measurements. No model inference is performed or charged. No predictive-performance or trading-return claim is made here.

HALOWERK handelswerk. Bezahlung über x402 in USDC auf Base Mainnet.

Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.

Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.

WhiteIntel — Corporate Ownership & Sanctions Intelligence. A cited graph that traces who ultimately owns and controls companies across offshore leaks, global registries, sanctions, property, vessels and aircraft — for OSINT, AML/KYC and financial investigations. Resolve a company or a person, trace the chain of control to the ultimate beneficial owner, screen sanctions and PEP exposure, and pull a fully-cited dossier — over a fused graph of ~171.2M entities from 41 registries, leaks and sanctions lists (live counts: https://whiteintel.dev/api/public/stats). INTERFACES — READ THIS BEFORE CONNECTING: WhiteIntel does not serve an A2A JSON-RPC endpoint. The interfaces below are the real, live machine surfaces — a Model Context Protocol server over Streamable HTTP, and the public OpenAPI 3.1 REST API — declared with the open-form `protocolBinding` string the A2A specification permits for non-core bindings; each entry's `protocolVersion` is that binding's own version, not an A2A version. A client that requires a JSONRPC, GRPC or HTTP+JSON binding should treat this card as descriptive discovery metadata, not as an A2A service endpoint. Every skill listed is anonymous and free to call.

Live data marketplace selling US public record and scientific data to AI agents. 8.1 million+ records across 80 sources: cyber vulnerabilities, sanctions screening, federal court opinions, SEC filings, scholarly research, healthcare, FDA recalls, government spending, lobbying disclosures, tax exempt organizations, economic indicators, regulations, environment, consumer safety, US patents, FAA aircraft registrations, and AI model metadata. Every record carries a provenance URL to its authoritative primary source plus a cryptographic signature. Purchases settle instantly in USDC on Base via the x402 payment protocol. Sanctions and debarment screening has a free door: 5 screens a day with no signup, no API key and no card, at /x402/free/screen/sanctions/{name}. Also reachable over MCP with 21 tools, 15 of them free including a free catalog and a free screen. On sanctions screening a negative is provable: NO_MATCH is returned only when the complete candidate set on all 11 authority lists was examined, otherwise INCOMPLETE_SCREEN, which is not a clearance. Every priced endpoint can be tried for free on the SAME URL by adding ?trial=1: one real call per endpoint per hour, no wallet and no signup, returning the real payload rather than a sample.