diff --git a/docs/reference.asciidoc b/docs/reference.asciidoc
index cc6343565..86c80ab5c 100644
--- a/docs/reference.asciidoc
+++ b/docs/reference.asciidoc
@@ -935,6 +935,7 @@ A post filter has no impact on the aggregation results.
 NOTE: This is a debugging tool and adds significant overhead to search execution.
 ** *`query` (Optional, { bool, boosting, common, combined_fields, constant_score, dis_max, distance_feature, exists, function_score, fuzzy, geo_bounding_box, geo_distance, geo_polygon, geo_shape, has_child, has_parent, ids, intervals, knn, match, match_all, match_bool_prefix, match_none, match_phrase, match_phrase_prefix, more_like_this, multi_match, nested, parent_id, percolate, pinned, prefix, query_string, range, rank_feature, regexp, rule_query, script, script_score, shape, simple_query_string, span_containing, field_masking_span, span_first, span_multi, span_near, span_not, span_or, span_term, span_within, term, terms, terms_set, text_expansion, weighted_tokens, wildcard, wrapper, type })*: Defines the search definition using the Query DSL.
 ** *`rescore` (Optional, { window_size, query, learning_to_rank } | { window_size, query, learning_to_rank }[])*: Can be used to improve precision by reordering just the top (for example 100 - 500) documents returned by the `query` and `post_filter` phases.
+** *`retriever` (Optional, { standard, knn, rrf })*: A retriever is a specification to describe top documents returned from a search. A retriever replaces other elements of the search API that also return top documents such as query and knn.
 ** *`script_fields` (Optional, Record<string, { script, ignore_failure }>)*: Retrieve a script evaluation (based on different fields) for each hit.
 ** *`search_after` (Optional, number | number | string | boolean | null | User-defined value[])*: Used to retrieve the next page of hits using a set of sort values from the previous page.
 ** *`size` (Optional, number)*: The number of hits to return.
diff --git a/src/api/api/search.ts b/src/api/api/search.ts
index b28d29735..6490428cc 100644
--- a/src/api/api/search.ts
+++ b/src/api/api/search.ts
@@ -46,7 +46,7 @@ export default async function SearchApi<TDocument = unknown, TAggregations = Rec
 export default async function SearchApi<TDocument = unknown, TAggregations = Record<T.AggregateName, T.AggregationsAggregate>> (this: That, params?: T.SearchRequest | TB.SearchRequest, options?: TransportRequestOptions): Promise<T.SearchResponse<TDocument, TAggregations>>
 export default async function SearchApi<TDocument = unknown, TAggregations = Record<T.AggregateName, T.AggregationsAggregate>> (this: That, params?: T.SearchRequest | TB.SearchRequest, options?: TransportRequestOptions): Promise<any> {
   const acceptedPath: string[] = ['index']
-  const acceptedBody: string[] = ['aggregations', 'aggs', 'collapse', 'explain', 'ext', 'from', 'highlight', 'track_total_hits', 'indices_boost', 'docvalue_fields', 'knn', 'rank', 'min_score', 'post_filter', 'profile', 'query', 'rescore', 'script_fields', 'search_after', 'size', 'slice', 'sort', '_source', 'fields', 'suggest', 'terminate_after', 'timeout', 'track_scores', 'version', 'seq_no_primary_term', 'stored_fields', 'pit', 'runtime_mappings', 'stats']
+  const acceptedBody: string[] = ['aggregations', 'aggs', 'collapse', 'explain', 'ext', 'from', 'highlight', 'track_total_hits', 'indices_boost', 'docvalue_fields', 'knn', 'rank', 'min_score', 'post_filter', 'profile', 'query', 'rescore', 'retriever', 'script_fields', 'search_after', 'size', 'slice', 'sort', '_source', 'fields', 'suggest', 'terminate_after', 'timeout', 'track_scores', 'version', 'seq_no_primary_term', 'stored_fields', 'pit', 'runtime_mappings', 'stats']
   const querystring: Record<string, any> = {}
   // @ts-expect-error
   const userBody: any = params?.body
diff --git a/src/api/types.ts b/src/api/types.ts
index bde49c300..159213070 100644
--- a/src/api/types.ts
+++ b/src/api/types.ts
@@ -665,8 +665,8 @@ export interface KnnSearchResponse<TDocument = unknown> {
 export interface KnnSearchQuery {
   field: Field
   query_vector: QueryVector
-  k: long
-  num_candidates: long
+  k: integer
+  num_candidates: integer
 }
 
 export interface MgetMultiGetError {
@@ -1167,6 +1167,7 @@ export interface SearchRequest extends RequestBase {
   profile?: boolean
   query?: QueryDslQueryContainer
   rescore?: SearchRescore | SearchRescore[]
+  retriever?: RetrieverContainer
   script_fields?: Record<string, ScriptField>
   search_after?: SortResults
   size?: integer
@@ -2294,17 +2295,26 @@ export interface KnnQuery extends QueryDslQueryBase {
   field: Field
   query_vector?: QueryVector
   query_vector_builder?: QueryVectorBuilder
-  num_candidates?: long
+  num_candidates?: integer
   filter?: QueryDslQueryContainer | QueryDslQueryContainer[]
   similarity?: float
 }
 
+export interface KnnRetriever extends RetrieverBase {
+  field: string
+  query_vector?: QueryVector
+  query_vector_builder?: QueryVectorBuilder
+  k: integer
+  num_candidates: integer
+  similarity?: float
+}
+
 export interface KnnSearch {
   field: Field
   query_vector?: QueryVector
   query_vector_builder?: QueryVectorBuilder
-  k?: long
-  num_candidates?: long
+  k?: integer
+  num_candidates?: integer
   boost?: float
   filter?: QueryDslQueryContainer | QueryDslQueryContainer[]
   similarity?: float
@@ -2443,6 +2453,12 @@ export interface QueryVectorBuilder {
   text_embedding?: TextEmbedding
 }
 
+export interface RRFRetriever extends RetrieverBase {
+  retrievers: RetrieverContainer[]
+  rank_constant?: integer
+  rank_window_size?: integer
+}
+
 export interface RankBase {
 }
 
@@ -2492,6 +2508,16 @@ export interface Retries {
   search: long
 }
 
+export interface RetrieverBase {
+  filter?: QueryDslQueryContainer | QueryDslQueryContainer[]
+}
+
+export interface RetrieverContainer {
+  standard?: StandardRetriever
+  knn?: KnnRetriever
+  rrf?: RRFRetriever
+}
+
 export type Routing = string
 
 export interface RrfRank {
@@ -2647,6 +2673,15 @@ export type SortOrder = 'asc' | 'desc'
 
 export type SortResults = FieldValue[]
 
+export interface StandardRetriever extends RetrieverBase {
+  query?: QueryDslQueryContainer
+  search_after?: SortResults
+  terminate_after?: integer
+  sort?: Sort
+  min_score?: float
+  collapse?: SearchFieldCollapse
+}
+
 export interface StoreStats {
   size?: ByteSize
   size_in_bytes: long
diff --git a/src/api/typesWithBodyKey.ts b/src/api/typesWithBodyKey.ts
index 84402cc8f..838b6dcd7 100644
--- a/src/api/typesWithBodyKey.ts
+++ b/src/api/typesWithBodyKey.ts
@@ -690,8 +690,8 @@ export interface KnnSearchResponse<TDocument = unknown> {
 export interface KnnSearchQuery {
   field: Field
   query_vector: QueryVector
-  k: long
-  num_candidates: long
+  k: integer
+  num_candidates: integer
 }
 
 export interface MgetMultiGetError {
@@ -1221,6 +1221,7 @@ export interface SearchRequest extends RequestBase {
     profile?: boolean
     query?: QueryDslQueryContainer
     rescore?: SearchRescore | SearchRescore[]
+    retriever?: RetrieverContainer
     script_fields?: Record<string, ScriptField>
     search_after?: SortResults
     size?: integer
@@ -2367,17 +2368,26 @@ export interface KnnQuery extends QueryDslQueryBase {
   field: Field
   query_vector?: QueryVector
   query_vector_builder?: QueryVectorBuilder
-  num_candidates?: long
+  num_candidates?: integer
   filter?: QueryDslQueryContainer | QueryDslQueryContainer[]
   similarity?: float
 }
 
+export interface KnnRetriever extends RetrieverBase {
+  field: string
+  query_vector?: QueryVector
+  query_vector_builder?: QueryVectorBuilder
+  k: integer
+  num_candidates: integer
+  similarity?: float
+}
+
 export interface KnnSearch {
   field: Field
   query_vector?: QueryVector
   query_vector_builder?: QueryVectorBuilder
-  k?: long
-  num_candidates?: long
+  k?: integer
+  num_candidates?: integer
   boost?: float
   filter?: QueryDslQueryContainer | QueryDslQueryContainer[]
   similarity?: float
@@ -2516,6 +2526,12 @@ export interface QueryVectorBuilder {
   text_embedding?: TextEmbedding
 }
 
+export interface RRFRetriever extends RetrieverBase {
+  retrievers: RetrieverContainer[]
+  rank_constant?: integer
+  rank_window_size?: integer
+}
+
 export interface RankBase {
 }
 
@@ -2565,6 +2581,16 @@ export interface Retries {
   search: long
 }
 
+export interface RetrieverBase {
+  filter?: QueryDslQueryContainer | QueryDslQueryContainer[]
+}
+
+export interface RetrieverContainer {
+  standard?: StandardRetriever
+  knn?: KnnRetriever
+  rrf?: RRFRetriever
+}
+
 export type Routing = string
 
 export interface RrfRank {
@@ -2720,6 +2746,15 @@ export type SortOrder = 'asc' | 'desc'
 
 export type SortResults = FieldValue[]
 
+export interface StandardRetriever extends RetrieverBase {
+  query?: QueryDslQueryContainer
+  search_after?: SortResults
+  terminate_after?: integer
+  sort?: Sort
+  min_score?: float
+  collapse?: SearchFieldCollapse
+}
+
 export interface StoreStats {
   size?: ByteSize
   size_in_bytes: long