missing_key

Summary

missing key `{1}` in `{0}`

Details

When this fires

A [key] lookup on a map didn't find the key at render time. The owner is a real map, the key is well-formed, it's just not present in the data your alert handed to the template. Logged when the action tries to send.

What to check

Map lookups are case-sensitive. Guard with default if the key is optional. nanook check only catches this when fixtures actually exercise the path, so for runtime-only data the default form is the safe play.

broken: {{ labels["env"] }}
fixed:  {{ labels["env"] | default("unknown") }}