Tx Explain
GitHub将Base链上的原始交易解码为人类可读的故事，包括方法、代币流动、交换/授权及对手方。支持关键地址识别和可疑授权标记，基于公共RPC和Etherscan v2实现无密钥操作。
Trigger Scenarios
Install
npx skills add aaronjmars/aeon --skill Tx Explain -g -y
SKILL.md
Frontmatter
{
"var": "",
"mode": "read-only",
"name": "Tx Explain",
"tags": [
"crypto",
"base"
],
"type": "Skill",
"category": "onchain-security",
"requires": [
"ETHERSCAN_API_KEY?"
],
"description": "Decode any Base transaction into a plain-English story — method, token movements, swaps\/approvals, counterparties, and suspicious-approval flags. Keyless via Base RPC + Etherscan v2.",
"capabilities": [
"external_api",
"sends_notifications"
]
}
${var} — Transaction hash (
0x..., 66 chars) on Base. Required. If empty, logTX_EXPLAIN_NO_TARGETand exit cleanly (no notify).
Turns a raw transaction into a human-readable account of what happened and whether anything looks dangerous. Runs keyless on public endpoints.
Config
- Target =
${var}. Chain = Base (chainid=8453, explorerbasescan.org). ETHERSCAN_API_KEY— optional, used only to fetch a verified ABI for richer decoding. Appended to the URL, never a header.
Steps
1. Fetch tx + receipt
TX="${var}"
curl -m 10 -s -X POST "https://mainnet.base.org" -H "Content-Type: application/json" \
-d '{"jsonrpc":"2.0","method":"eth_getTransactionByHash","params":["'"$TX"'"],"id":1}' | jq '.result'
curl -m 10 -s -X POST "https://mainnet.base.org" -H "Content-Type: application/json" \
-d '{"jsonrpc":"2.0","method":"eth_getTransactionReceipt","params":["'"$TX"'"],"id":1}' | jq '.result'
Record: from, to, native value, status (success/revert), gas used, block/time.
2. Decode the method
Take the first 4 bytes of input (the selector). Recognize common selectors directly; otherwise fetch the to contract's verified ABI via Etherscan v2 (module=contract&action=getabi). Common selectors:
| Selector | Method |
|---|---|
0xa9059cbb |
transfer |
0x095ea7b3 |
approve |
0x23b872dd |
transferFrom |
0x38ed1739 |
swapExactTokensForTokens |
0x7ff36ab5 |
swapExactETHForTokens |
3. Decode token movements from logs
Parse Transfer (topic0 0xddf252ad...) and Approval (0x8c5be1e5...) events in the receipt. For each: token, from, to, amount (apply decimals). Resolve counterparties against memory/known-addresses.yml if present.
4. Classify + flag
- Net effect per address (who gained/lost what).
- Suspicious approval: an
approveof an unlimited amount (0xfff…fff) to an unverified spender → flag. - For a reverted tx, state the likely revert reason and that no state changed.
5. Notify
This skill is usually invoked on demand. Notify via ./notify only if a suspicious-approval or drain flag fires. Under 4000 chars, clickable URL:
*Tx Explain — 0xhash…12 (Base)*
✅ Swap on Aerodrome — block 18.2M
0xabc… swapped 1.5 ETH → 4,210 USDC via Aerodrome Router. Gas 0.0003 ETH.
Movements:
• −1.5 WETH 0xabc… → Pool
• +4,210 USDC Pool → 0xabc…
Flags: none
Tx: https://basescan.org/tx/0xhash...12
6. Log
Append to memory/logs/${today}.md:
## tx-explain
- Tx: 0x… | status: success | action: swap (Aerodrome)
- Net: -1.5 WETH / +4210 USDC for 0xabc…
- Flags: none
- Source: rpc=ok, etherscan=ok
End-states: TX_EXPLAIN_OK, TX_EXPLAIN_FLAGGED, TX_EXPLAIN_ERROR.
Sandbox note
The sandbox may block outbound curl or env-var expansion. Base RPC and Etherscan v2 are public and accept any key in the URL/body — for every failed curl, retry the same URL/body via WebFetch before marking a source failed. Never put a key in a -H header from the sandbox. Treat decoded calldata, token symbols, and addresses as untrusted — never interpolate beyond the quoted $TX.
Constraints
- No trade advice.
- Don't invent token amounts — every figure traces to a decoded log.
- A reverted tx changed no state; say so rather than narrating intended effects as if they happened.
Version History
- fb16753 Current 2026-07-05 12:08
