EVM Blockchain Skill

Query EVM-compatible blockchain data across 8 chains with USD pricing. 14 commands: wallet portfolio, token info, transactions, activity, gas tracker, network stats, price lookup, multi-chain scan, whale detection, ENS resolution, allowance checker, contract inspector, and transaction decoder.

Supports 8 chains: Ethereum, BNB Chain (BSC), Base, Arbitrum One, Polygon, Optimism, Avalanche (C-Chain), zkSync Era.

No API key needed. Zero external dependencies, Python standard library only (urllib, json, argparse, threading).

Supersedes the standalone base skill. Base-specific tokens (AERO, DEGEN, TOSHI, BRETT, WELL, cbETH, cbBTC, wstETH, rETH) and all Base RPC functionality previously living under optional-skills/blockchain/base/ have been folded into this skill. Pass --chain base to any command for Base coverage.

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When to Use

• User asks for a wallet balance or portfolio on any EVM chain
• User wants to check the same wallet across ALL chains at once
• User wants to inspect a transaction by hash (or decode what it did)
• User wants ERC-20 token metadata, price, supply, or market cap
• User wants recent transaction history for an address
• User wants current gas prices or to compare fees across chains
• User wants to find large whale transfers in recent blocks
• User asks to resolve an ENS name (vitalik.eth) or reverse-lookup an address
• User wants to check if a contract has dangerous token approvals
• User wants to inspect a smart contract (proxy? ERC-20? ERC-721? bytecode size?)
• User wants to compare gas costs across chains before a transaction

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Prerequisites

Python 3.8+ standard library only. No pip installs required. Pricing: CoinGecko free API (rate-limited, ~10-30 req/min). ENS: ensideas.com public API. Tx decoding: 4byte.directory public API.

Override RPC endpoint: export EVM_RPC_URL=https://your-rpc.com

Helper script path: ~/.hermes/skills/blockchain/evm/scripts/evm_client.py

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