The Verifier smart contract emits events to log information about every intent execution and balance change. You can use these events to track on-chain actions, build indexers, and verify intent outcomes.
Event structure
Based on NEP-297, NEAR events are prefixed with the string EVENT_JSON. The Verifier contract emits events using the DIP-4 standard, which wraps event data in a JSON object with standard, version, event, and data fields.
Here is a token_diff event emitted after a successful trade:
EVENT_JSON:{
"standard": "dip4",
"version": "0.3.0",
"event": "token_diff",
"data": [
{
"account_id": "charlie.near",
"intent_hash": "5GpL6PsUQVHFYAk5FWEwBUaEQqcZkc2SjTvPYHgHAnx8",
"diff": {
"nep141:usdc.near": "-100",
"nep141:usdt.near": "100"
}
}
]
}
| Field | Description |
|---|
standard | Always "dip4". |
version | DIP-4 version (currently "0.3.0"). |
event | Event name (e.g., "token_diff", "intents_executed"). |
data | Array of event-specific payloads. |
Intent events
These events are directly related to submitted intents. See the full list of available events.
| Event | Description |
|---|
public_key_added | Emitted when a public key is added to an account. |
public_key_removed | Emitted when a public key is removed from an account. |
transfer | Emitted when a transfer between two accounts executes. |
token_diff | Emitted when a token_diff intent executes successfully. |
intents_executed | Emitted after successfully executing the listed intents. |
ft_withdraw | Emitted when a fungible token withdrawal intent is made. |
nft_withdraw | Emitted when an NFT withdrawal intent is made. |
mt_withdraw | Emitted when a multi-token withdrawal intent is made. |
native_withdraw | Emitted when a native NEAR withdrawal intent is made. |
storage_deposit | Emitted when a storage deposit intent is submitted. |
For withdrawal events, it is often difficult to emit only on success because the outcome depends on cross-contract calls.
Multi Token events
Multi Token events indicate changes in the internal balances of the Verifier contract. See the available events.
| Event | Description |
|---|
mt_mint | Emitted when the balance of a given account increases (due to deposits). |
mt_burn | Emitted when the balance of a given account decreases (due to withdrawals). |
mt_transfer | Emitted when tokens move between accounts (after executing intents like token_diff). |
Why “mint” and “burn”?
You can think of the Verifier as a set of isolated balances that can increase, decrease, or move between accounts. Although balances are conserved and simply moved between accounts, from the Verifier contract’s perspective:
- Increasing token amounts is equivalent to minting
- Decreasing token amounts is akin to burning
This design stems from how all tokens use the Multi Token standard for storage inside the Verifier smart contract. 
