Signed webhooks for EVM address activity. Point us at an address, tell us which
chains to watch, and get a cryptographically-signed POST whenever that
address sends a transaction, moves native value, or is involved in an ERC-20 or
ERC-721 transfer — so you can trust an event without having to replay it.
signingSecret so you can prove events came from us.webhook-id and verify the
HMAC signature, then trigger your own workflow.| Capability | Detail |
|---|---|
| Verified deliveries | HMAC-SHA256 signature over the exact event body
(webhook-signature: v1,<hex>, ±5 min replay tolerance) |
| Activity | Top-level txs (incl. zero-value and reverted), incoming native value,
ERC-20 and ERC-721 Transfers |
| Chains | All chains* |
| Idempotent | Deterministic webhook-id; dedupe safely (at-least-once) |
| Delivery ledger | 30-day history per webhook: every attempt, status, and outcome |
* Supported chains depend on evm.stupidtech.net — a chain is supported when it resolves there.
A signed delivery looks like this (hashes abbreviated):
{
"id": "evt_2f3d…",
"type": "activity.observed",
"createdAt": "2026-08-30T14:16:35.000Z",
"data": {
"chainId": 8453,
"trackedAddress": "0xa0bfe1a0fc5b83d16e8599fd…e405",
"initiatedByTrackedAddress": true,
"blockNumber": "50655024",
"transaction": {
"hash": "0x198a0a…698",
"index": 139,
"from": "0xa0bfe1a0fc5b83d16e8599fd…e405",
"to": "0x00000000000000000000000000000000000dEaD",
"status": "success",
"value": "100000000000000"
},
"effects": []
}
}
For an exchange of a token, data.effects carries the decoded
ERC-20 / ERC-721 transfer with the asset, counterparty, and
amount (token ids for ERC-721).
Transfers where the address is the sender or recipient.activity.reverted event.POST /v1/webhooks { "url": "https://you.example/hook" } → signing secret, once
POST /v1/subscriptions { "address": "0x1f9…", "chainIds":[8453,10,42161], "webhookId":"wh_…" }
GET /v1/webhook-deliveries
Agent-ready skills for this product live in the repo:
Full reference: API reference.
Access is provisioned per account (an operator issues your API key). For access or support, contact hi@stupidtech.net.