Delay steps accept IANA time zones and reject unknown ones

POST /api/v2/workflows/:workflow_id/steps and PATCH /api/v2/workflows/steps/:id now validate the time_zone inside step_type_settings.delay_step. Send the zone name the builder shows, such as Eastern Time (US & Canada), or a TZ database id such as America/New_York, which is stored as the name that keeps the same clock. Any other value comes back as a 422 instead of being saved.

Previously an unrecognized zone was accepted silently and stopped the workflow builder from loading that workflow until the step was removed. A delay step you create from code now behaves exactly like one created in the builder, whichever way you spell the zone.

Agent examples: schedule a Friday 10:30 send in the customer's local zone without looking up the label · build a workflow from code that a teammate can open and edit in the builder.

Resources: Workflow Step · Create Workflow Step · Time Zones guide. Building with an AI agent? Point it at the Workflows skill.