---

name: business-rule-patterns description: This skill should be used when the user asks to "create a business rule", "before insert", "after update", "async business rule", "business rule not working", "current vs previous", or any Business Rule development. version: 1.0.0 tools:

• snow_create_business_rule
• snow_find_artifact
• snow_edit_artifact
• snow_execute_script_with_output

---

Business Rule Best Practices for ServiceNow

Business Rules are server-side scripts that execute when records are displayed, inserted, updated, or deleted.

When to Use Each Type

Available Objects

Copy// In Business Rules, these are always available:
current   // The record being operated on
previous  // The record BEFORE changes (update/delete only)
gs        // GlideSystem utilities

Before Business Rules

Use for validation and field manipulation:

Copy// Prevent update if condition not met
(function executeRule(current, previous) {
  if (current.state == 7 && previous.state != 6) {
    current.setAbortAction(true);
    gs.addErrorMessage('Must resolve before closing');
  }
})(current, previous);

Copy// Auto-populate fields
(function executeRule(current, previous) {
  if (current.isNewRecord()) {
    current.setValue('caller_id', gs.getUserID());
    current.setValue('opened_by', gs.getUserID());
  }
})(current, previous);

Never do in Before rules:

• Call current.update() (causes recursion!)
• Query other tables (keep it fast)
• External API calls

After Business Rules

Use for related record operations:

Copy// Create child record when priority is P1
(function executeRule(current, previous) {
  if (current.priority.changesTo(1)) {
    var task = new GlideRecord('task');
    task.initialize();
    task.setValue('short_description', 'P1 Follow-up: ' + current.number);
    task.setValue('parent', current.sys_id);
    task.insert();
  }
})(current, previous);

Copy// Update parent record
(function executeRule(current, previous) {
  var parent = new GlideRecord('problem');
  if (parent.get(current.problem_id)) {
    parent.setValue('related_incidents', parent.related_incidents + 1);
    parent.update();
  }
})(current, previous);

Async Business Rules

Use for heavy processing that shouldn't block the transaction:

Copy// External integration
(function executeRule(current, previous) {
  var integrator = new ExternalSystemIntegration();
  integrator.syncIncident(current.sys_id);
})(current, previous);

Copy// Send custom notification
(function executeRule(current, previous) {
  gs.eventQueue('incident.priority.high', current, current.assigned_to, gs.getUserID());
})(current, previous);

Useful Methods

current Methods

Copycurrent.isNewRecord()           // True if insert
current.isValidRecord()         // True if record exists
current.getValue('field')       // Get field value
current.setValue('field', val)  // Set field value
current.setAbortAction(true)    // Cancel the operation
current.operation()             // 'insert', 'update', 'delete'
current.isActionAborted()       // Check if aborted

Field Change Detection

Copycurrent.priority.changes()        // Field changed (any value)
current.priority.changesTo(1)     // Changed TO this value
current.priority.changesFrom(3)   // Changed FROM this value
current.priority.nil()            // Field is empty

previous Comparisons

Copy// Check if field was modified
if (current.state != previous.state) {
  gs.info('State changed from ' + previous.state + ' to ' + current.state);
}

// Check specific change
if (current.assigned_to.changes() && !previous.assigned_to.nil()) {
  gs.info('Reassignment occurred');
}

Condition Examples

Use conditions to limit when the rule runs:

Performance Best Practices

1. Use conditions - Limit when the rule runs
2. Keep Before rules fast - No queries if possible
3. Use Async for integrations - Don't block transactions
4. Avoid Display rules - Slows form load
5. Set Order - Lower numbers run first (100-500 range)
6. Check "when to run" - insert, update, delete, query

Common Patterns

Auto-Assignment

Copy// Before Insert/Update
if (current.assignment_group.changes() && !current.assignment_group.nil()) {
  var members = new GroupMembers(current.assignment_group);
  current.assigned_to = members.getNextAvailable();
}

Cascade Updates

Copy// After Update
if (current.state.changesTo(7)) {  // Closed
  var tasks = new GlideRecord('task');
  tasks.addQuery('parent', current.sys_id);
  tasks.addQuery('state', '!=', 7);
  tasks.query();
  while (tasks.next()) {
    tasks.setValue('state', 7);
    tasks.update();
  }
}