Sim

Overview

Triggers are the core ways to start Sim workflows

Triggers Overview

Core Triggers

Use the Start block for everything originating from the editor, deploy-to-API, or deploy-to-chat experiences. Other triggers remain available for event-driven workflows:

Quick Comparison

TriggerStart condition
StartEditor runs, deploy-to-API requests, or chat messages
ScheduleTimer managed in schedule block
WebhookOn inbound HTTP request
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The Start block always exposes input, conversationId, and files fields. Add custom fields to the input format for additional structured data.

Using Triggers

  1. Drop the Start block in the start slot (or an alternate trigger like Webhook/Schedule).
  2. Configure any required schema or auth.
  3. Connect the block to the rest of the workflow.

Deployments power every trigger. Update the workflow, redeploy, and all trigger entry points pick up the new snapshot. Learn more in Execution → Deployment Snapshots.

Manual Execution Priority

When you click Run in the editor, Sim automatically selects which trigger to execute based on the following priority order:

  1. Start Block (highest priority)
  2. Schedule Triggers
  3. External Triggers (webhooks, integrations like Slack, Gmail, Airtable, etc.)

If your workflow has multiple triggers, the highest priority trigger will be executed. For example, if you have both a Start block and a Webhook trigger, clicking Run will execute the Start block.

External triggers with mock payloads: When external triggers (webhooks and integrations) are executed manually, Sim automatically generates mock payloads based on the trigger's expected data structure. This ensures downstream blocks can resolve variables correctly during testing.

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