Creating a Webhook
You create a webhook from the Webhooks section of the Spectrum dashboard. At the end, Spectrum shows a signing key once, so copy it then. If you miss it or lose it later, you can always rotate the key.
Create from the dashboard
Open Webhooks in the dashboard sidebar and click Create webhook. A four-step wizard walks you through the configuration.
1. Details
Give the webhook a recognisable name, pick the chain, and enter the HTTPS URL deliveries should be sent to.
2. Addresses
Add the addresses you want to watch. A delivery fires whenever one of them is the sender or receiver of matching activity. Press Enter to add each address.
3. Activity & tokens
Choose which activity categories trigger deliveries (select at least one), and optionally restrict ERC-20 events to specific token contracts. See Activity Categories for what each category means.
4. Review
Double-check the configuration, then click Create webhook. The retry-policy defaults shown here can be edited later from the webhook’s settings.
Save your signing key
Immediately after creation, Spectrum shows the signing key once in a modal. Copy it and store it securely, you will not be able to view it again. If you lose it, rotate the key from the webhook’s settings.
Your webhook is live. Next, set up your server to receive its deliveries: see Receiving Events for the payload your endpoint will get, and Signing & Verification to verify each delivery is genuinely from Spectrum. You can send a test delivery to confirm your endpoint works end-to-end.
Webhook settings
Everything the wizard collects can be reviewed and (where noted) edited later from the webhook’s settings.
| Setting | Notes |
|---|---|
| Name | A human-readable label for the webhook. |
| Chain | The chain to watch: Ethereum or Polygon. Set at creation and cannot be changed. |
| Destination URL | Where deliveries are sent. Must be https:// and publicly reachable; http:// and internal/non-routable addresses are rejected. |
| Watched addresses | The addresses to watch. An event matches when a watched address is the from or to side of the activity. |
| Activity categories | Which transfer types trigger deliveries: external, internal, ERC-20, ERC-721, ERC-1155. At least one is required. See Activity Categories. |
| ERC-20 token contracts | Optional. Restrict ERC-20 events to specific token contracts. Leave empty to receive any ERC-20 transfer involving a watched address. |
| Max delivery attempts | How many times a delivery is retried before it is dead-lettered. Default 5; set 0 to retry forever. See Delivery & Retries. |
| Retry interval | Base time between retry attempts. Default 60s, from 1s up to 1 day. |
A webhook is uniquely identified by its chain, destination URL, and filter (watched addresses, categories, and tokens). You can’t create a second webhook with an identical combination; the dashboard will point you to the existing one instead.
Editing a webhook
Open a webhook from the list and edit it from its settings. You can change the name, destination URL, watched addresses, activity categories, token filter, status, and retry policy.
- Chain cannot be changed after creation.
- Changing the destination URL re-runs the same HTTPS and safety checks as at creation.
- Setting the status to paused stops deliveries; setting it back to active resumes them. See Pausing and resuming.
Managing watched addresses
You set the initial list when you create the webhook. Afterwards, add or remove addresses from the webhook’s Addresses screen, no need to re-enter the whole list.
- Addresses are validated, lowercased, and de-duplicated automatically.
- Changes take effect on the next block Spectrum processes for that webhook.
Deleting a webhook
Delete a webhook from its settings. This is permanent, and any queued deliveries for that webhook are removed.