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Access to full transaction data on all transactions & addresses
Retrieve blockchain data, balances, and transactions
Detailed blockchain history and transaction data for any address.
Full smart contracts metadata, including token symbols & token names
Access to full transaction data on all transactions & addresses
Get live crypto prices, exchange rates, supply and token contracts across protocols via one REST API.
Real-time notifications for events on top blockchains. Response under 100ms.
AML address screening across 20+ blockchains
Sync and manage HD wallets, keys and addresses
Local signing for EVM, UTXO, Tron, XRP, Kaspa and Solana
Precise blockchain transaction fee estimates based on transaction priority
Broadcast and verify transactions with real-time monitoring
Prepare EVM transactions, including token transfers
Test EVM transactions, optimize gas fees and identify security flaws
Pay for HTTP APIs, or charge for your own, in USDC stablecoin over the open x402 protocol — non-custodial, on-chain settlement.
MCP servers, CLI and skills for AI agents
Dedicated nodes infrastructure for leading blockchains using JSON-RPC
Address validation, encoding & cryptographic tasks optimizations
Shared node infrastructure for top blockchains using JSON-RPC.
An agent that can read a chain is useful. One that can also move value is a different thing entirely — and the reason most teams stop at read-only is that handing a private key to a model is not an option.
It does not have to be. The agent prepares the transaction and broadcasts it; the signature happens with a key it never sees. Everything below runs on one API key.
Balances, transaction history, blocks, token holdings and market rates across 35+ networks — through MCP tools, a CLI, or plain REST. The agent asks a question and gets an answer it can act on.
MCP, CLI and agent skills →Prepare an unsigned transaction, sign it with a key the agent never holds, then broadcast. The agent orchestrates the workflow; custody stays where you put it.
Offline Signer →An agent that has to ask a human for a card cannot run unattended. x402 lets it settle for an API call in USDC over the open 402 Payment Required protocol, on-chain and non-custodial.
x402 Payments →The guide runs end to end on the free tier: connect the MCP server, read a balance, prepare a transfer, sign it locally and broadcast it.
Build with AI →This is the part that decides whether an agent is safe to run unattended. Addresses are derived from an xPub — a public key — so nothing the agent can reach will move funds. Transactions are prepared by the API and signed by @cryptoapis-io/offline-signer inside your own process: MIT-licensed, no API key, no network call. The agent hands the signed result back for broadcast and never sees the key that produced it.
The MCP server, the CLI and the whole read surface work on the free tier. No card to start.
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