What changes in test mode
Test mode is not a read-only mode — writes persist. Your sandbox
campaigns + leads share the tenant’s database with production. Use
distinct labels or a separate tenant if that bothers you.
Webhook subscription test_url
When creating a webhook subscription, you can optionally settest_url to a separate endpoint. Test-environment events POST there
instead of the production url. Common pattern:
How webhooks indicate environment
Every webhook delivery’sdata includes the originating call /
campaign, which carries the environment pinned at dial time (via
calls.dial_mode and related fields). To distinguish explicitly,
add a custom header or inspect the key that triggered the event —
we’ll add environment to the envelope in v1.1.

