List indices, one compact line each: name, health, status, document count and size in bytes. Large results are trimmed and say so.

List the fields of one index as dotted paths with their types, nested fields included, then the raw mapping. Give a concrete index name: an alias or a wildcard returns nothing.

Which fields exist across an index pattern and whether each is searchable and aggregatable. Takes a wildcard, unlike get_mappings, and is the only way to see a field mapped as two different types across indices — which makes an aggregation over it silently partial rather than failing.

Show the terms a text is broken into, which is what a query must produce to match. Pass field with index to use the analyzer that index really applies to that field; that is the form that explains a search returning nothing.

Search one index with a query DSL body. Matching text fields are highlighted. Paging goes inside queryBody (size, from); size is capped at 100 per call, so page with from for more.

Cluster health: status, node counts and shard counts.

Create a new index. Fails if it already exists — use create_mapping to add fields to an existing one.

Add or update fields on an index, creating the index if it does not exist. Elasticsearch cannot change the type of an existing field.

Index up to 1000 documents in one call. The index is refreshed by default, so they are searchable immediately; per-document failures are reported without failing the call.

Copy documents between indices. Asynchronous: returns a task id at once and the copy is still running on return — poll it with GET _tasks/.

Create or update a composable index template (Elasticsearch 7.8+). It applies only to indices created after it, never to existing ones.

Get composable index templates. Omit name to list all.

Count the documents matching a query, without transferring any. Cheaper than search when only the number matters.

Fetch one document by its _id. Reports that it is absent rather than failing.

List which aliases point to which indices. A name you query may be an alias, which changes what get_mappings returns.

Check an asynchronous task, such as the one reindex returns: progress, completion and failure.

Cluster name, Elasticsearch version and build flavour. The version decides which query DSL features exist.