Configure email broadcast subject-line split tests

You can now configure a two-subject A/B test when creating or updating an email broadcast. Keep the primary subject at the top level and add one alternate in variants, with the test audience share and wait time controlled by split_test_percentage and split_test_wait_time.

This lets an integration prepare the same subject-line experiment available in the dashboard without a manual editing step, while sending still stays behind the existing broadcast send action.

Agent examples: draft a newsletter with two subject lines · refine an alternate subject before scheduling.

Resources: Create Email Broadcast · Update Email Broadcast. Building with an AI agent? Point it at the Emails skill.