OneSignal

Push notification, email, SMS, and in-app messaging platform for customer engagement at scale.

Capabilities

Integration	Available	Notes
API	✓	Notifications, Users, Segments, Templates, Apps
MCP	-	Not available
CLI	✓	onesignal.js
SDK	✓	JavaScript, Node.js, Python, Java, PHP, Ruby, Go, .NET

Authentication

• Type: REST API Key (Basic Auth)
• Header: Authorization: Basic {REST_API_KEY}
• App ID: Required as app_id in request bodies
• Get credentials: Dashboard > Settings > Keys & IDs
• Security: HTTPS required, TLS 1.2+ on port 443

Common Agent Operations

Send push notification to segment

POST https://api.onesignal.com/api/v1/notifications

Headers:
  Authorization: Basic {REST_API_KEY}
  Content-Type: application/json

{
  "app_id": "YOUR_APP_ID",
  "included_segments": ["Subscribed Users"],
  "headings": { "en": "New Feature!" },
  "contents": { "en": "Check out our latest update." },
  "url": "https://example.com/feature"
}

Send notification to specific users

POST https://api.onesignal.com/api/v1/notifications

Headers:
  Authorization: Basic {REST_API_KEY}
  Content-Type: application/json

{
  "app_id": "YOUR_APP_ID",
  "include_aliases": { "external_id": ["user-123", "user-456"] },
  "target_channel": "push",
  "contents": { "en": "You have a new message." }
}

Schedule a notification

POST https://api.onesignal.com/api/v1/notifications

Headers:
  Authorization: Basic {REST_API_KEY}
  Content-Type: application/json

{
  "app_id": "YOUR_APP_ID",
  "included_segments": ["Subscribed Users"],
  "contents": { "en": "Scheduled notification" },
  "send_after": "2025-12-01 12:00:00 GMT-0500"
}

List notifications

GET https://api.onesignal.com/api/v1/notifications?app_id={APP_ID}&limit=50&offset=0

Headers:
  Authorization: Basic {REST_API_KEY}

View a notification

GET https://api.onesignal.com/api/v1/notifications/{notification_id}?app_id={APP_ID}

Headers:
  Authorization: Basic {REST_API_KEY}

Cancel a scheduled notification

DELETE https://api.onesignal.com/api/v1/notifications/{notification_id}?app_id={APP_ID}

Headers:
  Authorization: Basic {REST_API_KEY}

List segments

GET https://api.onesignal.com/api/v1/apps/{APP_ID}/segments

Headers:
  Authorization: Basic {REST_API_KEY}

Create a segment

POST https://api.onesignal.com/api/v1/apps/{APP_ID}/segments

Headers:
  Authorization: Basic {REST_API_KEY}
  Content-Type: application/json

{
  "name": "Active Users",
  "filters": [
    { "field": "session_count", "relation": ">", "value": "5" }
  ]
}

Get user by external ID

GET https://api.onesignal.com/api/v1/apps/{APP_ID}/users/by/external_id/{external_id}

Headers:
  Authorization: Basic {REST_API_KEY}

Create a user

POST https://api.onesignal.com/api/v1/apps/{APP_ID}/users

Headers:
  Authorization: Basic {REST_API_KEY}
  Content-Type: application/json

{
  "identity": { "external_id": "user-789" },
  "subscriptions": [
    { "type": "Email", "token": "user@example.com" }
  ],
  "tags": { "plan": "pro", "signup_source": "organic" }
}

List templates

GET https://api.onesignal.com/api/v1/templates?app_id={APP_ID}

Headers:
  Authorization: Basic {REST_API_KEY}

Key Metrics

Notification Metrics

• successful - Number of successful deliveries
• failed - Number of failed deliveries
• converted - Users who clicked/converted
• remaining - Notifications still queued
• errored - Count of errors
• opened - Notification open count

User Metrics

• session_count - Total user sessions
• last_active - Last activity timestamp
• tags - Custom key-value metadata
• subscriptions - Active subscription channels

Parameters

Notification Parameters

• app_id - Application ID (required)
• included_segments - Target segments array
• excluded_segments - Excluded segments array
• include_aliases - Target specific users by alias
• target_channel - Channel: push, email, sms
• contents - Message content by language code
• headings - Notification title by language code
• url - Launch URL on click
• data - Custom key-value data payload
• send_after - Scheduled send time (UTC string)
• ttl - Time to live in seconds

Segment Filter Fields

• session_count - Number of sessions
• first_session - First session date
• last_session - Last session date
• tag - Custom tag value
• language - User language
• app_version - App version
• country - User country code

When to Use

• Sending push notifications for product updates
• Triggered notifications based on user behavior
• Multi-channel messaging (push + email + SMS)
• Re-engagement campaigns for inactive users
• Segmenting users for targeted messaging
• A/B testing notification content
• Scheduling promotional campaigns

Rate Limits

• Free Plan: 150 notification requests/second per app
• Paid Plan: 6,000 notification requests/second per app
• User/Subscription ops: 1,000 requests/second per app
• Burst limit: No more than 10x total subscribers in 15 minutes
• 429 response: Includes RetryAfter header with seconds to wait

Relevant Skills

• push-notifications
• customer-engagement
• retention-campaign
• re-engagement
• lifecycle-marketing