"An overview of knowledge graphs" matching MCP connectors:
Matching Connector Tools:
Open AI Visibility Index for crypto and Web3. Weekly share-of-answer measurements for 24 tracked brands across ChatGPT, Perplexity and Gemini, from a frozen versioned prompt panel. Five read-only tools: full index, per-brand lookup, brand list, complete measurement history and methodology. No auth, no API key. Data is CC BY 4.0 with a permanent archive of every weekly snapshot, so any figure can be verified independently.
MCP server exposing 8 tools for trust scoring, sybil detection, reviewer wallet analysis, and counterparty risk across 150,000+ AI agents on ERC-8004, Olas, and Virtuals. Streamable HTTP, JSON-RPC 2.0, no API key required.
x402 game: take the crown, each take raises the next price 1.5x. hill_status is free.
Zero-install remote MCP server for proof-of-existence file attestation.
EVM gas, Chainlink prices, token-safety, swap quotes, ENS, OFAC & NFT via x402.
Ask what you can't be sure of. Read-only checks on tokens, NFTs, wallets and contracts.
Blockchain SSN for AI agents. MCP gateway that blocks at the point of action, tamper evident audit.
A colony of AI citizens: join with no credential, prove skills, earn, vote on the rules.
Screen an Ethereum address or ENS name for on-chain reputation risk, sanctions, and reasoning.
Verifiable agent DIDs + capability discovery — the passport & directory of the A2A economy.
Check a Base contract, transaction or web page before you act. Free pricing, paid per call in USDC.
The Graph MCP — indexed blockchain data via subgraph GraphQL queries
Verify on-chain lifecycle state and provenance of NFC-tagged physical products.
On-chain DEX aggregator quotes, phantom-liquidity scanning, and live proof-of-solvency across Base, Ethereum, Optimism, Arbitrum, and Robinhood Chain. Keyless, no auth.
Agent MCP for DeFi: cross-chain LINQ fan-out, AMM quotes/swaps, bridge, AI. Solana+EVM. Free+x402.
Gasless cross-chain for AI agents: 25 nodes incl. Solana & native Bitcoin. One signature, no gas.
An identity and memory layer for AI agents on the Emercoin blockchain. An agent claims a GitHub-rooted on-chain identity and stores verifiable hashes of its research and memory as Emercoin NVS (Name-Value Storage) records, through a small authenticated HTTP API and an MCP server. Neutral and provider-independent — not tied to any single AI vendor. FREE
Neutral W3C DID/VC identity and reputation oracle for AI agents (did:key/did:web, eddsa-jcs-2022).
Evidence-based market data for AI agents deploying capital in DeFi. Empirical, not advertised.