Skill Events

1. Open the Event Recorder in VS Code  ← VS Code command (not an agent tool)
2. Start recording
3. Execute the business process in BC (e.g., post a sales order)
4. Stop recording
5. Analyze the event list — filter by object or keyword
6. Identify the OnBefore/OnAfter event closest to your extension point

// Subscriber codeunit — name with "Handler" suffix
codeunit 50100 "Sales Document Events Handler"
{
    // Attribute breakdown:
    //   ObjectType  — Table, Codeunit, Page, Report, etc.
    //   ObjectId    — Database::"Sales Header" or Codeunit::"Customer Management"
    //   EventName   — exact name of the publisher procedure (e.g., OnBeforeInsert)
    //   ElementName — '' for table/codeunit events; field name for page field triggers
    //   SkipOnMissingLicense  — false (recommended: always run)
    //   SkipOnMissingPermission — false (recommended: always run)

    [EventSubscriber(ObjectType::Table, Database::"Sales Header",
                     OnBeforeInsert, '', false, false)]
    local procedure OnBeforeInsertSalesHeader(
        var SalesHeader: Record "Sales Header";
        RunTrigger: Boolean)
    begin
        ValidateCustomFields(SalesHeader);
    end;
}

codeunit 50101 "Customer Management"
{
    procedure CreateCustomer(var Customer: Record Customer): Boolean
    var
        IsHandled: Boolean;
    begin
        // 1. Raise OnBefore — subscribers can validate, modify, or skip
        OnBeforeCreateCustomer(Customer, IsHandled);
        if IsHandled then
            exit(true);

        // 2. Default logic
        if not Customer.Insert(true) then
            exit(false);

        // 3. Raise OnAfter — subscribers can react (logging, integration, etc.)
        OnAfterCreateCustomer(Customer);
        exit(true);
    end;

    [IntegrationEvent(false, false)]
    local procedure OnBeforeCreateCustomer(
        var Customer: Record Customer;
        var IsHandled: Boolean)
    begin
        // Empty body — subscribers provide the implementation
        // IsHandled = true → skip default logic
    end;

    [IntegrationEvent(false, false)]
    local procedure OnAfterCreateCustomer(var Customer: Record Customer)
    begin
        // Empty body — subscribers react after creation
    end;
}

[BusinessEvent(IncludeSender)]
local procedure OnCustomerCreditLimitExceeded(
    Customer: Record Customer;
    RequestedAmount: Decimal)
begin
    // Subscribers may send notification, log, or block — user can disable
end;

// ✅ Good — rich context, var where modification expected, IsHandled for OnBefore
[IntegrationEvent(false, false)]
local procedure OnBeforePostDocument(
    var DocumentHeader: Record "Sales Header";   // var — subscriber may modify
    var DocumentLines: Record "Sales Line";      // var — subscriber may modify
    PostingDate: Date;                           // value — read-only context
    var IsHandled: Boolean)                      // var — subscriber may skip default
begin
end;

// ✅ Good — results context for OnAfter
[IntegrationEvent(false, false)]
local procedure OnAfterPostDocument(
    DocumentHeader: Record "Sales Header";       // value — read-only (already posted)
    PostedDocumentNo: Code[20];                  // result reference
    PostingResult: Boolean)                      // success/failure
begin
end;