Send push, email, and SMS messages, manage Users, Subscriptions, and Segments, and track custom events via the OneSignal REST API.
OneSignal ships in the w6w first-party pack. It declares 19 actions, 2 health checks, and the host runs its code in a sandbox that never sees the credential.
io.w6w.onesignalOneSignal is a customer messaging and engagement platform: push notifications (mobile and web), email, SMS, and in-app messages, targeted at Users, Subscriptions, or Segments and orchestrated through Journeys.
This app covers the app-scoped REST surface a backend integration needs: sending a message on any channel (push, email, SMS) with segment, alias, subscription-id, or property-filter targeting; estimating a send’s audience before it goes out; reading, listing, and cancelling messages; creating, reading, updating, and deleting Users and their Subscriptions; creating, listing, and deleting Segments; and recording custom events that drive Journeys and segmentation.
Authentication is the App API key OneSignal introduced in November 2024 (os_v2_app_...), scoped to one App ID — the legacy REST API key and User Auth key still work but their management UI is gone and no new ones can be created, so this app is built against the current key only. Health checks track OneSignal’s own status page alongside the credential’s liveness; OneSignal exposes no readable API rate-limit headroom, which is declared rather than guessed at.
Three routes to the same 19 actions. The Workflow tab is generated from OneSignal's own manifest and carries its real ids, so it is copy-pasteable; the Code and CLI examples are the same call for any action on any app, so every app-specific value in them is a blank you fill in.
create-custom-event Record a custom event for a user, to trigger Journeys or drive segmentation.
estimate-recipients Preview the audience size for a targeting configuration before sending.
send-push Send a push notification to segments, subscriptions, aliases, or a filter.
update-subscription Update a Subscription's token, enabled state, or opt-in status.
A workflow step names the app and the action, and the editor fills in the
connection when you pick one. This is the Step shape from the
workflow spec, carrying OneSignal's real ids.
{
"manifestVersion": "2",
"name": "onesignal-example",
"steps": [
{
"id": "create-custom-event",
"uses": {
"app": "io.w6w.onesignal",
"action": "create-custom-event",
"connection": "conn_YOUR_CONNECTION_ID"
},
"with": {
"name": "<name>"
}
}
]
}create-custom-event create-segment create-subscription create-user estimate-recipients +14 more actions available
Every app-specific value here is a blank you have to fill in. An
app action is reached through the connection that authenticates it, so the
address is a connection id, not the app id — and connections belong to your account,
so a public page cannot know yours. Create one for OneSignal, then fill in
the three blanks: conn_YOUR_CONNECTION_ID, the action key, and the
parameters that action declares. The call itself is real — the shape is transcribed
from the studio's own snippet builder, which prints the same kind of blanks — but
nothing in it is specific to OneSignal. The Workflow tab is where this app's
real ids are.
npm install @w6w/sdkyarn add @w6w/sdkpnpm add @w6w/sdkdeno add npm:@w6w/sdkimport { W6wClient, isActionRun } from "@w6w/sdk";
// Reads W6W_BASE_URL and W6W_TOKEN from the environment when omitted.
const client = new W6wClient();
const envelope = await client.run({
urn: "conn_YOUR_CONNECTION_ID",
action: "create-custom-event",
payload: {
name: "<value>",
// externalId: "<value>",
// onesignalId: "<value>",
// properties: "<value>",
// timestamp: "<value>",
// idempotencyKey: "<value>",
},
});
if (isActionRun(envelope)) console.log(envelope.value); npm install -g @w6w/cli w6w run conn_YOUR_CONNECTION_ID --action create-custom-event --payload '{"name":"<value>"}' Give an AI agent OneSignal — without giving it OneSignal's credentials. One MCP endpoint exposes every app, function and workflow the caller is entitled to, as tools it can discover and run. Access is granted per team while we onboard.
One tool call{
"name": "w6w_invoke",
"arguments": {
"ref": "app:io.w6w.onesignal#create-custom-event",
"input": {
"name": "<name>"
}
}
}
Every tool names its target with a single ref. The
app: form above doesn't name a connection at all — the
host resolves which of the caller's OneSignal connections to sign
with, and refuses rather than guesses when the answer is ambiguous.
The token is attached host-side, at the moment of the call. It is never a tool argument, never in the model's context, and never in a transcript — so a prompt injection has nothing to exfiltrate.
Tools are derived per end user from what that person has actually connected and is entitled to — not one shared bot identity carrying the union of everyone's access.
Multi-step work runs on the workflow engine and returns a run handle the agent can poll — retries, branching and state survive the conversation that started them.
OneSignal's declared health checks are on the surface too, so an agent can tell "the vendor is down" from "your credential expired" before it burns a retry on either.
The MCP surface is part of the hosted platform. OneSignal itself is MIT, and the runtime that executes it is source-available (FSL).
OneSignal declares its own checks, so its health is a property of the app rather than something the host guesses at.
Component status from status.onesignal.com — Push, Email, SMS, In-App Messages, Journeys, Integrations, Analytics & Reporting, APIs & SDK Endpoints, and Dashboard / UI.