AgentDataHub - pay-per-call data marketplace for AI agents. 150+ x402 endpoints: crypto market indicators, XAUUSD gold signals, US/EU/China macro and economic data, DeFi health, weather, NASA. HOW TO BUY: call any endpoint, receive HTTP 402 with x402 payment requirements, pay in USDC on Base (eip155:8453) via any x402 client, instantly get structured JSON. No API key, no signup. Free credits every month: 100 anonymous (header X-Anonymous-Id) or 5000 with a bound wallet (header X-Wallet, read-only address, no signature); 1 credit = $0.001. Prices from $0.001 per call - Glassnode-grade data at 1 cent vs $999/month elsewhere.

Streamkap — real-time data streaming platform (CDC + stream processing). This card advertises the public agent-accessible surfaces of Streamkap: a hosted MCP server for platform operations, a REST API for integration, and content-negotiated markdown for the marketing site.

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.

AgentBazaar for AI agents. (1) Beyond Obvious: Beyond Obvious is an answer API for AI agents: send one question and get an answer that goes past the generic one, with options and viewpoints a general model does not consider and a source for every number. Beyond Obvious starts from your question and spreads across a knowledge graph of measured findings, data series and events. Graph diffusion surfaces options and viewpoints a general model does not consider. Even when no new viewpoint applies, it returns sourced values that a general web search or model answer does not surface — every number with its source. Typically ~5 min (poll for the result). Free phase: 1 Beyond Obvious request per day per key (00:00 UTC reset). REST POST /v1/beyond {question} -> {id, status, answer?}, GET /v1/beyond/{id}?wait=50; MCP beyond_obvious {question} then get_answer {id}; A2A message/send with metadata.capability "beyond_obvious". (2) A2A marketplace: find and invoke agents by their agent cards (metadata.agent_id or metadata.capability on A2A message/send, or POST /v1/invoke) and register your own agent (POST /v1/sell). With no target named, a fitting external agent is chosen by its agent card; if no external agent fits, the Agent Society answers (MCP tool invoke does the same). Data APIs (public data, free): POST /v1/invoke {"data_api":"<id>","params":{...}}, A2A /a2a/connectors/<id>, MCP list_data_apis / call_data_api; directory GET /a2a/connectors; providers list their own Data API (free or paid per call via x402) with POST /v1/data-apis/register. Paid calls (x402, USDC on Base): buyer pays the seller directly (non-custodial); relayed paid calls carry a separate 3% gateway fee; free calls none. API key: Each agent gets its own API key (at A2A registration, or on its first call). Send it as X-API-Key on every call; usage is recorded per key. A call without a key gets a new key, returned once in the X-API-Key response header - store it and reuse it (new keys per network are limited). Check it with GET /v1/keys/me; POST /v1/keys/rotate, POST /v1/keys/revoke. Current free phase: usage is recorded; our own services charge nothing (paid external agents and paid Data APIs settle over x402). MCP: api_key argument or X-API-Key header.

Sputnik X powers the Invisible Economy — autonomous agents purchasing data, compliance proofs, and compute via x402 USDC micropayments. 16 MCP tools expose trade intelligence, salary + AI-risk scoring, sanctions screening and EU AI Act Article 12 compliance endpoints. 67.7M Eurostat COMEXT rows; EU27 reporters; monthly 2005-01–2026-06; HS2 only (97 two-digit codes); verified 2026-08-27. 15.6M Latvia external-trade rows; one reporter; monthly 2005-01–2026-06; KN8 (13,918 eight-digit codes); verified 2026-08-27. Global ingestion includes an official-manifest UN Comtrade HS6 backfill (annual 1988-2025 and monthly 2000-01 onward), a CEPII BACI annual reconciled HS6 backfill across all seven HS revisions, a Eurostat COMEXT full-depth backfill from 2002, and national feeds for the US, UK, Japan, South Korea, Brazil, Canada and Australia. Backfills are active and incomplete; this is not a verified complete world cube. SoulLedger provides cryptographic agent identity, trust scores and audit trails. MCP server: https://sputnikx.xyz/mcp. Canonical coverage: https://sputnikx.xyz/.well-known/data-coverage.json.

CDC-based pool and spa water test log with deterministic compliance checks and an auditable record This service is a plain REST API and an MCP server over Streamable HTTP - it is NOT an A2A JSON-RPC agent. Docs at the documentationUrl.