block-explorer

name	block-explorer
description	Query Etherscan/Basescan for on-chain data. Transaction lookup, contract source, gas prices, token holders, and internal transactions.
metadata	{"openclaw":{"emoji":"🔍"}}

Block Explorer — Etherscan/Basescan

When to Use

• User asks "what happened in this transaction?"
• User wants to see contract source code or ABI
• User asks about current gas prices
• User wants to know who holds a token (top holders)
• User wants to trace internal transactions
• User asks about a contract's verification status

When NOT to Use

• Checking token prices (use defi-trading skill)
• Monitoring real-time on-chain activity (use watch-activity skill)
• Technical analysis (use analytics skill)

Tool: block_explorer

Actions

Action	Description
tx_lookup	Transaction details: status, gas, value, from/to
contract_source	Verified source code, ABI, compiler info, proxy status
gas_tracker	Current gas prices: fast/standard/slow + cost estimates
token_holders	Top token holders with balance and percentage
internal_txs	Internal (trace) transactions for an address or tx

Parameters

Param	Required For	Description
chain	All (optional)	"base" (default) or "ethereum"
tx_hash	tx_lookup, internal_txs	Transaction hash (0x...)
address	contract_source, internal_txs	Contract or wallet address (0x...)
token	token_holders	Token contract address
page	token_holders, internal_txs	Page number (default: 1)
limit	token_holders, internal_txs	Results per page (default: 25, max: 100)

Environment Variables

Variable	Required For
BASESCAN_API_KEY	Base chain queries
ETHERSCAN_API_KEY	Ethereum chain queries

Get free API keys at:

• https://basescan.org/apis
• https://etherscan.io/apis

Workflow

1. Look up a transaction:

   action: tx_lookup, tx_hash: 0xabc123..., chain: base
   

   Returns: status, block, from/to, value, gas used, gas cost in ETH.

2. Check contract source:

   action: contract_source, address: 0x833589..., chain: base
   

   Returns: verified status, contract name, source code, ABI, proxy info.

3. Check gas prices:

   action: gas_tracker, chain: base
   

   Returns: fast/standard/slow in gwei + estimated costs for ETH transfer, ERC-20 transfer, and swap.

4. Find top token holders:

   action: token_holders, token: 0xa1F7..., chain: base, limit: 10
   

   Returns: holder addresses, balances, percentage of supply.

5. Trace internal transactions:

   action: internal_txs, tx_hash: 0xabc123..., chain: base
   

   Returns: internal calls with from/to/value/type.

Gas Cost Estimates

The gas_tracker action includes pre-computed cost estimates for common operations:

Operation	Typical Gas
ETH transfer	21,000
ERC-20 transfer	65,000
Swap	200,000

Security Notes

• API keys are used for rate limiting, not authentication — Etherscan data is public
• Contract source may not match deployed bytecode if not verified
• Always verify contract addresses through multiple sources before interacting