"US Government Open Data API Aggregator (FEC, SEC, Congress, Lobbying, USAspending)" matching MCP connectors:

Live multi-asset market data for AI agents with provenance, starter credits, x402, and examples.

Structured iGaming reference: slot specs & RTP variants, providers, regulators, news and jobs.

UK property data — Land Registry comps, EPC, Rightmove, rental yields, stamp duty, Companies House

Teardrop is the native economic layer for AI agents, providing a robust suite of tools for multi-chain portfolio tracking, DeFi yield analysis, and gas estimation. It enables autonomous agents to securely find Web3 data and manage micro-payments on-chain with zero human intervention.

Structured aquarium, marine, terrarium and paludarium data for AI agents.

CatchAll is a web search API built for comprehensive event retrieval — not ranked results, but all matching records.

Public data intelligence for AI agents — CVE, compliance, patents, contracts, domains.

Cross-venue Polymarket+Kalshi arbitrage: resolution mismatch, void risk & settlement divergence.

Detect breaking changes, generate changelogs, diff, and validate OpenAPI specs.

Free platform to test MCP clients without installing anything. Create mock tools with dynamic templates, configurable delays, conditions (if/then), and response sequences. Supports JSON-RPC 2.0 over Streamable HTTP. Built-in text_echo and json_echo tools. Rate-limited tiers: anonymous (5 calls/min, 1 mock tool), registered (10 calls/min, 4 mock tools), premium (60 calls/min, unlimited). Zero setup — no install, no registration required. More info: https://www.testmcp.dev

Eligibility-first UK & EU grant discovery, inside ChatGPT and Claude. Checks eligibility before recommending, explains why each grant fits, and cites the funder's own page on every answer — with an honest "competition_risk: unknown" when the data isn't there. 6 tools: search, fetch, find_opportunities, should_apply, explain_opportunity, complete_profile. Transport: Streamable HTTP. Auth: OAuth 2.1 + PKCE. Free to install, no card required.

Pay-per-use tool API for AI agents. Free tier, x402 USDC micropayments, or API key.

Universal pay-per-call tool API for AI agents. Web search, price feeds, hive memory, LLM routing, code sandbox. Free tier (10 calls/day, no signup). x402 payments on Base + Solana.

Secureship MCP gives AI assistants access to a multi-carrier shipping API covering rate comparison, label generation, package tracking, pickup scheduling, address book management, shipment history, customs documents, and more — across carriers like UPS, FedEx, Purolator, Canpar, and others. Browse 150+ live endpoint schemas, parameters, and auth details — always current, never stale.

Real-time options analytics MCP server. Access gamma exposure (GEX), delta exposure (DEX), vanna exposure (VEX), dealer positioning, volatility surfaces, Black-Scholes greeks, implied volatility solver, and key options levels for any US equity — all through natural language. 14 read-only tools covering exposure metrics, volatility analysis, pricing, and market data.

Search PubChem compounds, properties, safety data, bioactivity, and cross-references.

Search 14.5M Smithsonian Open Access objects, get CC0 images, find cross-collection connections.

Query SEC EDGAR filings, XBRL financials, and company data through MCP. STDIO & Streamable HTTP.

Find air-quality stations and read pollutant observations from government monitors via OpenAQ v3.

Access US federal award, recipient, agency, and spending analytics data from USAspending.gov.