From version 5.0 onward, Watcher is part of X-Pack. For more information, see Alerting on cluster and index events.
Elastic Docs ›Elasticsearch Watcher [1.0] ›Managing Watches
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Listing Watchesedit

Watcher stores watches in the .watches index. You can search this index to see what watches are configured.

You can only perform read actions on the .watches index. You must use the Watcher APIs to create, update, and delete watches. If you are using Shield, we recommend only granting users read privileges for the .watches index.

To get the ids of all configured watches, run the following search query:

GET .watches/_search
{
	"fields" : [], 
	"query" : {"match_all" : { } }
}

If you omit the fields option, the search returns the full watch definition and status of each watch.
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