Blockchain And Crypto x402 offerings

Crypto Fear & Greed Index (0-100) with classification. Data source: Alternative.me (attribution included in the response).

Reference data for a blockchain by its chainId: name, gas/native token, block explorers, number of public RPCs and website. Utility for multi-chain agents. Live from chainid.network (ethereum-lists, …

Crypto Fear & Greed Index (0-100) with classification. Data source: Alternative.me (attribution included in the response).

Price change in % of up to 20 cryptocurrencies over 1h, 24h or 7d, sorted from best to worst, with current price. Tickers of the ~190 largest coins (alternative.me data).

Staking rewards: final amount, total rewards and average per day and month, with daily compounding or simple, after validator commission, in tokens and optionally in USD.

Detect and validate a crypto address before sending funds: EVM (EIP-55 checksum), Solana, Bitcoin (legacy, P2SH, SegWit, Taproot), Litecoin, Dogecoin, Tron and Cosmos bech32, with its type and networ…

Build the transaction that revokes a contract's permission over an ERC-20 token (approve(spender, 0)): target and calldata ready to sign in your wallet. Nothing is sent.

Current price of a list of cryptocurrencies by ticker (BTC, ETH, SOL...) or chain:contract, in USD or any ECB currency (EUR, GBP, JPY...). The simplest way to get prices.

Price change in % of up to 20 tokens over 1h, 24h, 7d, 30d, 90d or 1y, sorted from best to worst, with current price. Symbols or chain:contract ids. DefiLlama data.

Encode a contract function call (calldata) from its signature and arguments, e.g. transfer(address,uint256) with [to, amount]: selector and hex data ready to sign or simulate.

Value a crypto portfolio such as {"BTC": 0.1, "ETH": 2}: current value and weight of each holding and total; with a start date, its value then, return, annualized volatility and maximum drawdown. Pri…

Test your x402 client or agent for the minimum price: confirms the payment arrived and echoes back the network, scheme, payer and amount the server saw, your IP, user agent, time and any 'eco' text y…

Perpetual futures calculator (isolated margin): liquidation price and distance, notional and size, PnL at stop-loss and take-profit, reward/risk ratio, and position sizing to risk a fixed USD amount.

Compute a contract address in advance: CREATE (deployer + nonce) or CREATE2 (deployer + salt + init code hash). For deterministic deployments and verifying announced addresses.

Trusted UTC time (NTP-synced server clock) with millisecond Unix timestamps, ISO week and the latest Ethereum and Base block times as independent references. For timestamping and clock checks.

Staking rewards: final amount, total rewards and average per day and month, with daily compounding or simple, after validator commission, in tokens and optionally in USD.

Detect and validate a crypto address before sending funds: EVM (EIP-55 checksum), Solana, Bitcoin (legacy, P2SH, SegWit, Taproot), Litecoin, Dogecoin, Tron and Cosmos bech32, with its type and networ…

Current price of up to 50 cryptocurrencies by ticker (BTC, ETH, SOL, XRP...) in USD or any ECB currency (EUR, GBP, JPY...). Covers the ~190 largest coins listed by alternative.me; currency conversion…

Explain an EIP-712 typed-data signature before signing it: x402/EIP-3009 payment authorizations, EIP-2612 permits, Permit2 and Seaport orders. Flags unlimited allowances, long validity and non-offici…

Collateralized DeFi loan (Aave/Compound style): health factor, current LTV, collateral liquidation price, drop it can withstand, extra borrowing room and how much to repay or add to reach a 1.5 healt…

Explain an EIP-712 typed-data signature before signing it: x402/EIP-3009 payment authorizations, EIP-2612 permits, Permit2 and Seaport orders. Flags unlimited allowances, long validity and non-offici…

Daily history of the crypto Fear & Greed Index (0 extreme fear, 100 extreme greed): average, max, min, days in each zone and trend, with the series. Alternative.me data.

Crypto price in any ECB currency (EUR, GBP, JPY, CHF...): on-chain USD price (Chainlink or Uniswap v3) converted with ECB reference rates.

Decode EVM calldata (transaction input) with the function signature you provide, checking that it matches the selector, or decode return data with its output types (e.g. uint256,address). Local calcu…