Testing & sandbox

Test keys hit a full sandbox that never sends real messages. Use magic numbers to trigger every status and error.

Applies to

Sandbox request

1# Placeholder: Fernway is a fictional API.
2# Test keys start with fw_test_ and never deliver real messages.
3curl https://api.fernway.example/v2/messages \
4  -H "Authorization: Bearer $FERNWAY_TEST_KEY" \
5  -d to="+15555550100" \
6  -d channel="sms" \
7  -d body="Sandbox check"
8 
9# +15555550100 -> delivered
10# +15555550101 -> failed (carrier_rejected)
11# +15555550102 -> stays queued for 60 s

How the sandbox works

Every account has a sandbox. Requests made with a test key (fw_test_) run through the same validation, rate limits and webhooks as live traffic, but nothing leaves Fernway and nothing is billed.

Magic numbers

Send to these placeholder numbers to force an outcome without waiting on a carrier:

+15555550100 is delivered within a second.
+15555550101 fails with carrier_rejected.
+15555550102 stays queued for 60 seconds, then is delivered.
Any address at sandbox.fernway.example works the same way for email.

Sandbox webhooks

Webhook endpoints registered in test mode only receive test events. Keep a separate endpoint for each mode so a test event can never touch production data.

Placeholder API

Fernway is a fictional product used to show how this template works. Replace these docs with your own in the CMS.

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