Add clarification to semantic_text documentation on default quantization and lexical search support (elastic#128927)

* Add clarifications to semantic text documentation

* Regnerate match ESQL docs

* Fix whitespace

* PR feedback

* Update docs/reference/elasticsearch/mapping-reference/semantic-text.md

Co-authored-by: Liam Thompson <[email protected]>

---------

Co-authored-by: Liam Thompson <[email protected]>

Author: 2 people

docs/reference/elasticsearch/mapping-reference/semantic-text.md

@@ -28,7 +28,10 @@ service.
 
 Using `semantic_text`, you won’t need to specify how to generate embeddings for
 your data, or how to index it. The {{infer}} endpoint automatically determines
-the embedding generation, indexing, and query to use.
+the embedding generation, indexing, and query to use. 
+Newly created indices with `semantic_text` fields using dense embeddings will be
+[quantized](/reference/elasticsearch/mapping-reference/dense-vector.md#dense-vector-quantization)
+to `bbq_hnsw` automatically.
 
 If you use the preconfigured `.elser-2-elasticsearch` endpoint, you can set up
 `semantic_text` with the following API request:
@@ -246,10 +249,15 @@ is not supported for querying the field data.
 
 ## Updates to `semantic_text` fields [update-script]
 
-For indices containing `semantic_text` fields, updates that use scripts have the following behavior:
+For indices containing `semantic_text` fields, updates that use scripts have the
+following behavior:
 
-* Are supported through the [Update API](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-update).
-* Are not supported through the [Bulk API](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-bulk-1) and will fail. Even if the script targets non-`semantic_text` fields, the update will fail when the index contains a `semantic_text` field.
+* Are supported through
+  the [Update API](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-update).
+* Are not supported through
+  the [Bulk API](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-bulk-1)
+  and will fail. Even if the script targets non-`semantic_text` fields, the
+  update will fail when the index contains a `semantic_text` field.
 
 ## `copy_to` and multi-fields support [copy-to-support]
 
@@ -311,4 +319,5 @@ PUT test-index
   of [nested fields](/reference/elasticsearch/mapping-reference/nested.md).
 * `semantic_text` fields can’t currently be set as part
   of [Dynamic templates](docs-content://manage-data/data-store/mapping/dynamic-templates.md).
-* `semantic_text` fields are not supported with Cross-Cluster Search (CCS) or Cross-Cluster Replication (CCR).
+* `semantic_text` fields are not supported with Cross-Cluster Search (CCS) or
+  Cross-Cluster Replication (CCR).

docs/reference/query-languages/esql/_snippets/functions/description/match.md

@@ -11,7 +11,9 @@ Returns documents that match a provided text, number, date or boolean value. The
 
 The `match` query is the standard query for performing a full-text search, including options for fuzzy matching.
 
-`Match` will also work against [semantic_text](/reference/elasticsearch/mapping-reference/semantic-text.md) fields, however when performing `match` queries against `semantic_text` fields options that specifically target lexical search such as `fuzziness` or `analyzer` will be ignored.
+`Match` will also work against [semantic_text](/reference/elasticsearch/mapping-reference/semantic-text.md) fields. 
+As `semantic_text` does not support lexical text search, `match` queries against `semantic_text` fields will automatically perform the correct semantic search.
+Because of this, options that specifically target lexical search such as `fuzziness` or `analyzer` will be ignored.
 
 ## Example request [match-query-ex-request]
 

docs/reference/query-languages/esql/kibana/definition/functions/match.json

@@ -142,6 +142,7 @@ public class Match extends FullTextFunction implements OptionalArgument, PostAna
 
             Match can be used on fields from the text family like <<text, text>> and <<semantic-text, semantic_text>>,
             as well as other field types like keyword, boolean, dates, and numeric types.
+            When Match is used on a <<semantic-text, semantic_text>> field, it will perform a semantic query on the field.
 
             Match can use <<esql-function-named-params,function named parameters>> to specify additional options for the match query.
             All <<match-field-params,match query parameters>> are supported.