--- title: "Evm — Read-only EVM client: wallets, tokens, gas across 8 chains" sidebar_label: "Evm" description: "Read-only EVM client: wallets, tokens, gas across 8 chains" --- {/* This page is auto-generated from the skill's SKILL.md by website/scripts/generate-skill-docs.py. Edit the source SKILL.md, not this page. */} # Evm Read-only EVM client: wallets, tokens, gas across 8 chains. ## Skill metadata | | | |---|---| | Source | Optional — install with `hermes skills install official/blockchain/evm` | | Path | `optional-skills/blockchain/evm` | | Version | `1.0.0` | | Author | Mibayy (@Mibayy), youssefea (@youssefea), ethernet8023 (@ethernet8023), Hermes Agent | | License | MIT | | Platforms | linux, macos, windows | | Tags | `EVM`, `Ethereum`, `BNB`, `BSC`, `Base`, `Arbitrum`, `Polygon`, `Optimism`, `Avalanche`, `zkSync`, `Blockchain`, `Crypto`, `Web3`, `DeFi`, `NFT`, `ENS`, `Whale`, `Security` | | Related skills | [`solana`](/docs/user-guide/skills/optional/blockchain/blockchain-solana) | ## Reference: full SKILL.md :::info The following is the complete skill definition that Hermes loads when this skill is triggered. This is what the agent sees as instructions when the skill is active. ::: # 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. --- ## 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 --- ## 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` --- ## Quick Reference ``` SCRIPT=~/.hermes/skills/blockchain/evm/scripts/evm_client.py # Network & prices python3 $SCRIPT stats # Ethereum stats python3 $SCRIPT stats --chain arbitrum # Arbitrum stats python3 $SCRIPT compare # Gas + prices ALL 8 chains # Wallet python3 $SCRIPT wallet 0xd8dA...96045 # Portfolio (ETH + ERC-20) python3 $SCRIPT wallet 0xd8dA...96045 --chain bsc python3 $SCRIPT multichain 0xd8dA...96045 # Same wallet on ALL chains # Tokens & prices python3 $SCRIPT price ETH python3 $SCRIPT price 0xdAC1...1ec7 # By contract address python3 $SCRIPT token 0xdAC1...1ec7 # ERC-20 metadata + market cap # Transactions python3 $SCRIPT tx 0x5c50...f060 # Transaction details python3 $SCRIPT decode 0x5c50...f060 # Decode input data (4byte.directory) python3 $SCRIPT activity 0xd8dA...96045 # Recent transactions # Gas python3 $SCRIPT gas # Gas prices + cost estimates python3 $SCRIPT gas --chain optimism # Security python3 $SCRIPT allowance 0xd8dA...96045 # Dangerous ERC-20 approvals python3 $SCRIPT contract 0xdAC1...1ec7 # Contract inspection (proxy? standards?) # ENS python3 $SCRIPT ens vitalik.eth # Name -> address + profile python3 $SCRIPT ens 0xd8dA...96045 # Address -> ENS name # Whale detection python3 $SCRIPT whale # Large transfers (last 20 blocks, >$10k) python3 $SCRIPT whale --blocks 50 --min-usd 100000 --chain arbitrum ``` --- ## Procedure ### 0. Setup Check ```bash python3 --version # 3.8+ required python3 ~/.hermes/skills/blockchain/evm/scripts/evm_client.py stats ``` ### 1. Wallet Portfolio Native balance + known ERC-20 tokens, sorted by USD value. ```bash python3 $SCRIPT wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 python3 $SCRIPT wallet 0xd8dA... --chain bsc --no-prices # faster ``` ### 2. Multi-Chain Scan Scans all 8 chains simultaneously for the same address using threads. ```bash python3 $SCRIPT multichain 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 ``` Output: per-chain native balance + token holdings + grand total USD. ### 3. Compare (Gas + Prices) All 8 chains queried in parallel. Shows cheapest/most expensive chain. ```bash python3 $SCRIPT compare ``` ### 4. Transaction Details & Decode ```bash python3 $SCRIPT tx 0x5c504ed432cb51138bcf09aa5e8a410dd4a1e204ef84bfed1be16dfba1b22060 python3 $SCRIPT decode 0x5c504ed... # Shows human-readable function signature ``` Decode uses 4byte.directory to translate 0xa9059cbb -> transfer(address,uint256). ### 5. ENS Resolution ```bash python3 $SCRIPT ens vitalik.eth # -> 0xd8dA... + avatar + social links python3 $SCRIPT ens 0xd8dA...96045 # -> vitalik.eth ``` ### 6. Allowance Checker (Security) Checks ERC-20 approvals granted to known DEX/bridge contracts. ```bash python3 $SCRIPT allowance 0xYourWallet ``` Flags UNLIMITED approvals as HIGH risk. ### 7. Contract Inspector ```bash python3 $SCRIPT contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 # USDC (proxy) python3 $SCRIPT contract 0xdAC17F958D2ee523a2206206994597C13D831ec7 # USDT (ERC-20) ``` Detects: proxy (EIP-1967/EIP-1167), ERC-20, ERC-721, ERC-165. Shows bytecode size and implementation address for proxies. ### 8. Whale Detection ```bash python3 $SCRIPT whale # ETH, last 20 blocks, >$10k python3 $SCRIPT whale --blocks 50 --min-usd 50000 --chain bsc ``` ### 9. Gas Tracker ```bash python3 $SCRIPT gas python3 $SCRIPT gas --chain polygon ``` Shows gwei price + USD cost for: transfer, ERC-20 transfer, approve, swap, NFT mint, NFT transfer. --- ## Supported Chains | Key | Name | Native | Chain ID | |-----------|----------------|--------|----------| | ethereum | Ethereum | ETH | 1 | | bsc | BNB Chain | BNB | 56 | | base | Base | ETH | 8453 | | arbitrum | Arbitrum One | ETH | 42161 | | polygon | Polygon | POL | 137 | | optimism | Optimism | ETH | 10 | | avalanche | Avalanche C | AVAX | 43114 | | zksync | zkSync Era | ETH | 324 | --- ## Pitfalls - CoinGecko free tier: ~10-30 req/min. Use `--no-prices` for faster wallet scans. - Public RPCs may throttle. Set EVM_RPC_URL to a private endpoint for production. - `wallet` and `allowance` only check known token list (~30 tokens per chain). Use a block explorer for complete token discovery. - `activity` scans recent blocks only (max 200). For full history, use Etherscan API. - `multichain` runs 8 parallel threads — can trigger rate limits on public RPCs. - ENS resolution depends on a single public endpoint (ensideas.com / ens.vitalik.ca) with no fallback. If that endpoint is down, `ens` will fail — re-run later or use a block explorer. - Tx decoding depends on a single public endpoint (4byte.directory) with no fallback. Selectors not in their database show up as `unknown`. - **L2 gas estimates are L2-execution only.** On rollups like Base, Arbitrum, Optimism, and zkSync, the actual transaction cost also includes an L1 data-posting fee that depends on calldata size and current L1 gas prices. The `gas` command does not estimate that L1 component. For Base specifically, see the network's L1 fee oracle (contract `0x420000000000000000000000000000000000000F`). - Address / tx-hash inputs are validated for 0x-prefix + correct length + hex, but EIP-55 checksum casing is **not** enforced (RPC endpoints accept any-case hex). --- ## Verification ```bash # Should print current block, gas price, ETH price python3 ~/.hermes/skills/blockchain/evm/scripts/evm_client.py stats # Should resolve vitalik.eth to 0xd8dA... python3 ~/.hermes/skills/blockchain/evm/scripts/evm_client.py ens vitalik.eth ```