# Blockscout External Transactions Lookup

> Blockscout External Transactions Lookup is a paid API for AI agents from api.blockscout.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-12).

Retrieves external (internal) transactions associated with a specific transaction hash on a given blockchain network via Blockscout's multichain explorer API

## Facts

- Endpoint: GET https://api.blockscout.com/%7Bchain_id%7D/api/v2/transactions/%7Btransaction_hash_param%7D/external-transactions
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blockscout-external-transactions-lookup-ee228498
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_K8KTTZo1nMtosZMPHAW3w

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 blockscout-external-transactions-lookup-ee228498
```

Example prompt: Can you pull up all the external transactions triggered by the transaction hash 0xabc123...def on Ethereum (chain ID 1) using Blockscout?

## When to prefer this

Choose this endpoint when you need to inspect the internal/external sub-transactions spawned by a specific on-chain transaction across any of Blockscout's supported networks. It is ideal for tracing smart contract interactions, auditing DeFi operations, or verifying that all value transfers within a complex transaction executed correctly. Prefer this over generic block explorers when you need programmatic multichain access with a consistent API interface.

## Known failure modes

- Invalid or unknown chain_id returns an error or empty result
- Malformed transaction hash returns a 400 or 422 validation error
- Transaction hash not found on the specified chain returns an empty array or 404
- Network timeout or Blockscout node unavailability returns a 5xx error
- Transaction has no external transactions, returning an empty array

## How this service works

Explore crypto activities with Blockscout's multichain search. Find transactions, addresses, tokens, and dapps across top blockchain networks — your go-to explorer for cross-chain blockchain data

## Output

A JSON array of external (internal) transaction records associated with the given transaction hash on the specified blockchain, including details such as value transfers, contract calls, and sub-transaction metadata generated by the top-level transaction.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "properties": {
      "chain_id": {
       "type": "string"
      },
      "transaction_hash_param": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": [
  "string"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/blockscout-external-transactions-lookup-ee228498/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.blockscout.com](https://www.zero.xyz/host/api.blockscout.com/llms.txt)