A single webhook can monitor multiple addresses, you don’t need to create one webhook per address.
In the free plan, you add up to 5 addresses per webhook. If you need more than that you can upgrade your plan.

​
Creating the webhook

Let’s start by creating a new webhook to monitor all USDC and USDT activity: 
curl --location 'https://glacier-api.avax.network/v1/webhooks' \
--header 'x-glacier-api-key: <YOUR_API_KEY>' \
--header 'Content-Type: application/json' \
--data '{
    "url": "https://webhook.site/4eb31e6c-a088-4dcb-9a5d-e9341624b584",
    "chainId": "43114",
    "eventType": "address_activity",
    "includeInternalTxs": true,
    "includeLogs": true,
    "metadata": {
        "addresses": [
            "0x9702230A8Ea53601f5cD2dc00fDBc13d4dF4A8c7",
            "0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E"
            ]
    },
    "name": "Tokens",
    "description": "Track tokens"
}
It returns the following: 
{
    "id": "401da7d9-d6d7-46c8-b431-72ff1e1543f4",
    "eventType": "address_activity",
    "chainId": "43114",
    "metadata": {
        "addresses": [
            "0x9702230A8Ea53601f5cD2dc00fDBc13d4dF4A8c7",
            "0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E"
        ]
    },
    "includeInternalTxs": true,
    "includeLogs": true,
    "url": "https://webhook.site/4eb31e6c-a088-4dcb-9a5d-e9341624b584",
    "status": "active",
    "createdAt": 1715621587726,
    "name": "Tokens",
    "description": "Track tokens"
}

​
Adding addresses to monitor

With the webhook id we can add more addresses. In this case, let’s add the contract addresses for JOE and PNG: 
curl --location --request PATCH 'https://glacier-api.avax.network/v1/webhooks/401da7d9-d6d7-46c8-b431-72ff1e1543f4/addresses' \
--header 'x-glacier-api-key: <YOUR_API_KEY>' \
--header 'Content-Type: application/json' \
--data '{
  "addresses": [
            "0x6e84a6216eA6dACC71eE8E6b0a5B7322EEbC0fDd",
            "0x60781C2586D68229fde47564546784ab3fACA982"
  ]
}
Following that, we will begin to receive events from the four smart contracts integrated into the webhook: USDC, USDT, JOE, and PNG.

​
Deleting addresses

To remove addresses, simply send an array: 
curl --location --request DELETE 'https://glacier-api.avax.network/v1/webhooks/401da7d9-d6d7-46c8-b431-72ff1e1543f4/addresses' \
--header 'x-glacier-api-key: <YOUR_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
  "addresses": [
    "0x735D8f3B6A5d2c96D0405230c50Eaf96794FbB88"
  ]
}