generated: '2026-08-27'
method: searched
source: https://docs.simbachain.com/documentation/simba-build/subscriptions
docs: https://docs.simbachain.com/documentation/simba-build/subscriptions
type: Webhooks
description: >-
  SIMBA Blocks has a real event surface — Subscriptions — but publishes NO AsyncAPI document, so this
  artifact captures the webhook/notification catalog from SIMBA's own documentation instead. A
  subscription fires when a transaction is extracted from the blockchain and matches a filter. Three
  delivery transports are supported out of the box: http(s) webhooks, mailto and SMS, plus custom
  endpoints with custom message templates. Subscriptions are implicitly bound to an organisation.
asyncapi_published: false
asyncapi_probed:
  - url: https://blocks.simbachain.com/asyncapi.json
    status: 200
    note: SPA catch-all HTML shell, not a document.
  - url: https://docs.simbachain.com/documentation/llms.txt
    status: 200
    note: >-
      The complete published documentation index — 100 pages — contains no AsyncAPI, event-catalog or
      CloudEvents page.
transports:
  - name: http
    description: HTTP(S) webhook POST to a subscriber-supplied endpoint.
    field: endpoint
  - name: mailto
    description: Email notification.
    field: endpoint
  - name: sms
    description: SMS notification.
    field: endpoint
  - name: custom
    description: >-
      Custom endpoints and custom message templates configured through NotificationConfig; the
      Template entity in the member service holds the message templates.
subscription_object:
  fields:
    id: UUID for the object.
    created_on: Date time the database row was created.
    updated_on: Date time the database row was last updated.
    endpoint: The endpoint to notify. http(s), mailto and SMS are supported.
    txn: >-
      The transaction name — a method name for a contract method, an event name for a contract event,
      'payment' for a payment, or 'constructor' for a contract deployment.
    contract: >-
      Optional. A deployed contract specified by its HTTP API name; required when the subscription is
      to a contract method.
    subscription_type: One of METHOD, CREATION, EVENT, PAYMENT.
    auth_type: >-
      The authentication type used when delivering the notification. Must match a configured
      NotificationConfig auth_type, or be empty to use the default notification configuration.
    filters: Array of {parameter, op, value} filters evaluated against the transaction.
event_types:
  - type: METHOD
    trigger: A contract method was invoked.
    txn_field: the method name
    filterable_on: the method's input parameters, plus _sender
  - type: EVENT
    trigger: A Solidity/chaincode event associated with a contract was emitted.
    txn_field: the event name
    filterable_on: the event's parameters, plus _sender
  - type: CREATION
    trigger: A contract deployment transaction.
    txn_field: constructor
    filterable_on: the constructor inputs, plus _sender
  - type: PAYMENT
    trigger: A payment transaction.
    txn_field: payment
    filterable_on: [value, from, to, _sender]
subscription_scopes:
  - name: Application subscription
    description: Created from Subscriptions -> Applications -> New Event; bound to an application, contract and method or event.
  - name: Wallet subscription
    description: Created from Subscriptions -> Wallets -> New Event; bound to a wallet account.
  - name: Account subscription
    description: Subscriptions were extended to include Accounts in Blocks v23.8.1.
filter_operators:
  strings: [exact, contains, icontains, startswith, endswith, in]
  numbers: [equals, gt, gte, lt, lte, in]
  boolean: [is]
  universal_field: _sender (the transaction's from address; supported by every subscription type)
prerequisites:
  - Log in to the SIMBA dashboard.
  - Select an organisation.
  - Create an application.
  - Create a smart contract.
  - Deploy the created smart contract in the application.
delivery_semantics:
  signing: not documented
  retries: not documented
  ordering: not documented
  note: >-
    SIMBA documents no webhook signing scheme, no retry/backoff policy and no delivery-ordering
    guarantee. A consumer cannot verify a delivered notification came from SIMBA except by the
    configured auth_type on the NotificationConfig. Recorded as a gap, not inferred.
gaps:
  - No AsyncAPI (or CloudEvents) document is published for this surface.
  - Subscription CRUD is performed in the UI in the documentation; release notes reference "subscription APIs" and breaking changes to "subscription-related endpoints" (Blocks v24.1.1), but no subscription endpoint is documented in the public API reference and none appears in either published OpenAPI.