# OpenVerbs Chain Transaction Explainer

> OpenVerbs Chain Transaction Explainer is a paid API for AI agents from chain.openverbs.com, paid per call via x402, $0.006/call, status unknown (last checked 2026-09-13).

Decodes an on-chain transaction hash into plain-language summary including transfer type, decoded method, ERC-20/NFT token movements, gas cost, and status

## Facts

- Endpoint: POST https://chain.openverbs.com/v1/explain
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/openverbs-chain-transaction-explainer-3bd6b5ea
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_umutX09AY0G4oaXaziADD

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability openverbs-chain-transaction-explainer-3bd6b5ea -d '<json body>'
```

Example prompt: Can you explain what happened in this Ethereum transaction — 0x4e6f6e636500000000000000000000000000000000000000000000000000dead — like what method was called, what tokens moved, how much gas was used, and whether it succeeded?

## When to prefer this

Choose this endpoint when you need a human-readable explanation of a specific transaction — especially for DeFi swaps, ERC-20 transfers, NFT mints, or contract calls — across Ethereum, Base, Arbitrum, Optimism, or Polygon. It is ideal when you want decoded method names, token movement details from logs, and a plain-language summary in a single call rather than stitching together raw RPC calls. Prefer sibling endpoints for raw tx data without explanation, or for block/address-level queries.

## Known failure modes

- Invalid or malformed transaction hash returns validation error
- Transaction not found on the specified chain returns not-found error
- Unsupported chain name returns enum validation error
- Unrecognized contract method may return raw 4-byte selector instead of decoded name
- Pending transactions may have incomplete receipt data
- Network congestion or RPC fallback delays may increase latency
- Microtransaction fee of $0.006 USDC must be paid per call via x402 protocol

## How this service works

Decode a transaction into plain language: native ETH transfer, contract call (with decoded method name for common ERC-20/DEX functions like transfer, approve, swap, mint, multicall) or contract creation; ERC-20 and NFT (ERC-721) transfers it triggered (token, from, to, amount/tokenId from logs); gas spent in ETH; success/failed/pending; and a one-line summary. Reads live on-chain data with automatic endpoint fallback.

## Output

A plain-language explanation of the transaction including: the type (native ETH transfer, contract call, or contract creation), the decoded method name for common functions (transfer, approve, swap, mint, multicall, etc.), a list of ERC-20 and ERC-721 (NFT) token transfers triggered by the transaction with from/to/amount or tokenId, total gas spent in ETH, transaction status (success/failed/pending), and a concise one-line summary.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "hash": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{64}$",
       "description": "32-byte transaction hash."
      },
      "chain": {
       "type": "string",
       "enum": [
        "ethereum",
        "base",
        "arbitrum",
        "optimism",
        "polygon"
       ],
       "description": "EVM chain to query. One of: ethereum, base, arbitrum, optimism, polygon. Default \"ethereum\"."
      }
     },
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/openverbs-chain-transaction-explainer-3bd6b5ea/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chain.openverbs.com](https://www.zero.xyz/host/chain.openverbs.com/llms.txt)