Is it possible to use kibana.alert.reason within the actions. I have tried
{{#context.alerts}}{{kibana.alert.reason}}{{/context.alerts}}
Is it possible to use kibana.alert.reason within the actions. I have tried
{{#context.alerts}}{{kibana.alert.reason}}{{/context.alerts}}
Hey there @probson! 
So I just tested this on an 8.0 snapshot and am seeing it work, so my guess it has to do with the field aliasing between kibana.alert.reason and signal.reason for pre-8.x. Looking at the source for 7.16, it looks like reason is being set on signal.reason, so you should be able to use that to access the reason in actions, ala:
{{#context.alerts}}{{signal.reason}}{{/context.alerts}}
Let me know if that doesn't work (and your Kibana version), and happy to dig further! Cheers! 
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