Event Types Reference

Event kind strings in Off the Hook follow the pattern <scope>.<entity>.<status>. Because chainId and asset information are always present in the payload data object, one handler covers every chain and every asset type — you never need separate subscriptions for TRX versus TRC-20 tokens, or for mainnet versus testnet. Add one or more of the kind strings below to the events array when creating or updating a subscription.

Available events

`wallet.transfer.broadcasted`

Fired when a TRX or TRC-20 transfer is confirmed in a new block. This is the primary event for monitoring wallet activity. TRC-20 token transfer

{
  "id": "evt_8xN9kP2QbA...",
  "kind": "wallet.transfer.broadcasted",
  "date": "2026-05-08T12:34:56Z",
  "data": {
    "chainId": "tron:mainnet",
    "blockNumber": 78912345,
    "blockHash": "00000000...",
    "blockTimestamp": 1730000000000,
    "txId": "abc123...",
    "logIndex": 0,
    "from": "TLsV52sRDL79HXGGm9yzwKibb6BeruhUzy",
    "to": "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t",
    "amount": "1500000000",
    "asset": {
      "type": "fungible",
      "contract": "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t",
      "symbol": "USDT",
      "decimals": 6
    },
    "matchedAddresses": [
      { "chainId": "tron:mainnet", "address": "TLsV52sRDL79HXGGm9yzwKibb6BeruhUzy", "role": "from" }
    ]
  }
}

Native TRX transfer For native TRX, asset.type is "native", contract is null, and logIndex is -1. The -1 value is intentional — it distinguishes a native transfer from the first TRC-20 log in the same transaction, which uses index 0.

{
  "id": "evt_...",
  "kind": "wallet.transfer.broadcasted",
  "date": "2026-05-08T12:34:56Z",
  "data": {
    "chainId": "tron:mainnet",
    "blockNumber": 78912345,
    "blockHash": "00000000...",
    "blockTimestamp": 1730000000000,
    "txId": "xyz789...",
    "logIndex": -1,
    "from": "TLsV52sRDL79HXGGm9yzwKibb6BeruhUzy",
    "to": "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t",
    "amount": "1000000",
    "asset": {
      "type": "native",
      "contract": null,
      "symbol": "TRX",
      "decimals": 6
    },
    "matchedAddresses": [
      { "chainId": "tron:mainnet", "address": "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t", "role": "to" }
    ]
  }
}

When Off the Hook encounters a TRC-20 contract it has no metadata for, asset.symbol and asset.decimals are both null. Your code should handle these null values and display the raw amount string rather than attempting to format it.

Payload field reference

Field	Type	Description
`id`	string	Unique event identifier, prefixed `evt_`
`kind`	string	Always `wallet.transfer.broadcasted` for this event
`date`	string	ISO 8601 timestamp when the event was created
`data.chainId`	string	CAIP-2 chain identifier (e.g. `tron:mainnet`)
`data.blockNumber`	integer	Block height where the transfer was confirmed
`data.blockHash`	string	Hash of the confirming block
`data.blockTimestamp`	integer	Block timestamp in milliseconds since Unix epoch
`data.txId`	string	Transaction ID on the TRON network
`data.logIndex`	integer	Log index within the transaction; `-1` for native TRX transfers
`data.from`	string	Sender address (TRON base58check)
`data.to`	string	Recipient address (TRON base58check)
`data.amount`	string	Transfer amount as a raw integer string, in the asset’s smallest unit
`data.asset.type`	string	`"native"` for TRX, `"fungible"` for TRC-20 tokens
`data.asset.contract`	string \| null	TRC-20 contract address; `null` for native TRX
`data.asset.symbol`	string \| null	Token symbol (e.g. `"USDT"`); `null` if contract is unknown
`data.asset.decimals`	integer \| null	Decimal places for the asset; `null` if contract is unknown
`data.matchedAddresses`	array	Which of your watched addresses triggered the event and their role (`"from"` or `"to"`)

`service.ping`

A system event fired by the POST /v1/subscriptions/:id/test endpoint. Use it to verify that your endpoint is reachable and returning 2xx responses before you start monitoring live chain activity.

{
  "id": "evt_...",
  "kind": "service.ping",
  "date": "2026-05-08T12:00:00Z",
  "data": {}
}

Planned events

These event kinds are not yet available. Do not include them in your events array — the API returns an unsupported_event error if you do.

wallet.transfer.confirmed

Fired after a transfer receives enough block confirmations to be considered final. Requires polling for confirmation depth — planned for a future release.

wallet.transfer.failed

Fired when a transfer transaction is detected as reverted or failed. Requires revert detection logic — planned for a future release.

wallet.contract_call.broadcasted

Fired when a smart contract call appears in a new block. Planned for a future release.

wallet.contract_call.confirmed

Fired after a contract call reaches confirmation depth. Planned for a future release.

wallet.contract_call.failed

Fired when a contract call is reverted. Planned for a future release.

wallet.balance.crossed_threshold

Fired when a wallet balance crosses a configured threshold in either direction. Planned for a future release.

Get Started

Core Concepts

Guides

Reference

Available events

`wallet.transfer.broadcasted`

`service.ping`

Planned events

​Available events

​wallet.transfer.broadcasted

​service.ping

​Planned events

Available events

`wallet.transfer.broadcasted`

`service.ping`

Planned events