Triggers

Triggers are the events that start your automations. Every flow must have exactly one trigger.

Schedule Trigger

Run your automation on a recurring schedule.

Options:

• Every X minutes — Run at fixed intervals (1, 5, 15, 30 minutes)
• Every X hours — Run hourly at a specific minute
• Daily — Run once per day at a specific time
• Weekly — Run on specific days of the week
• Monthly — Run on a specific day of the month
• Custom Cron — Full cron expression for advanced scheduling

Example cron expressions:

*/5 * * * *     # Every 5 minutes
0 9 * * 1-5     # 9 AM on weekdays
0 0 1 * *       # Midnight on the 1st of each month
0 */2 * * *     # Every 2 hours

Use cases: Daily reports, periodic data sync, scheduled cleanups, recurring notifications.

Webhook Trigger

Receive HTTP requests at a unique URL to start your flow.

Configuration:

• URL — Auto-generated unique endpoint
• Method — GET, POST, PUT, DELETE, PATCH, or any
• Authentication — None, Basic Auth, Header Auth, or Query Parameter
• Response mode — Respond immediately (202 Accepted) or after workflow completes (with custom body)

Example webhook URL:

https://engine.onflowstack.com/webhook/a1b2c3d4-e5f6-7890-abcd-ef1234567890

Use cases: Form submissions, CI/CD pipelines, third-party app notifications, IoT device events.

App Event Trigger

Start your flow when something happens in a connected app.

Popular app triggers:

App	Trigger Events
Gmail	New Email, New Labeled Email, New Attachment
Slack	New Message, New Mention, Reaction Added
Google Sheets	New Row, Updated Row
GitHub	New PR, New Issue, Push Event
Stripe	New Payment, Subscription Created, Invoice Paid
HubSpot	New Contact, Deal Stage Changed, Form Submitted
Notion	Page Created, Page Updated, Database Item Added
Typeform	New Response
Calendly	New Booking, Booking Cancelled

Setup:

1. Select the app trigger
2. Connect your account (OAuth popup or API key)
3. Configure trigger-specific settings (e.g., which inbox, which channel)
4. Test the trigger to verify it receives events

Manual Trigger

Run the automation on-demand.

How to trigger manually:

• Click Run on any automation in the dashboard
• Use the Test Flow button inside the builder
• Call the REST API: POST /api/v1/flow-runs with the flow ID

Use cases: One-time data migrations, on-demand reports, testing and debugging.

Trigger Data

Every trigger provides data to the subsequent actions. This data is accessible using expressions:

// Schedule trigger
{{ trigger.scheduledTime }}

// Webhook trigger
{{ trigger.body }}          // POST body
{{ trigger.headers }}       // HTTP headers
{{ trigger.query }}         // Query parameters

// App trigger (varies by app)
{{ trigger.email.subject }} // Gmail new email
{{ trigger.message.text }}  // Slack new message