diff --git a/specification/_global/get/types.ts b/specification/_global/get/types.ts
index 534c0feace..1b99beba8c 100644
--- a/specification/_global/get/types.ts
+++ b/specification/_global/get/types.ts
@@ -17,10 +17,14 @@
  * under the License.
  */
 
-import { Id, IndexName, SequenceNumber, VersionNumber } from '@_types/common'
+import {
+  Id,
+  IndexName,
+  SequenceNumber,
+  UserDefinedObject,
+  VersionNumber
+} from '@_types/common'
 import { long } from '@_types/Numeric'
-import { Dictionary } from '@spec_utils/Dictionary'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
 export class GetResult<TDocument> {
   /**
@@ -30,7 +34,7 @@ export class GetResult<TDocument> {
   /**
    * If the `stored_fields` parameter is set to `true` and `found` is `true`, it contains the document fields stored in the index.
    */
-  fields?: Dictionary<string, UserDefinedValue>
+  fields?: UserDefinedObject
   _ignored?: string[]
   /**
    * Indicates whether the document exists.
diff --git a/specification/_global/search/SearchResponse.ts b/specification/_global/search/SearchResponse.ts
index f813c67aeb..7d613fb9e1 100644
--- a/specification/_global/search/SearchResponse.ts
+++ b/specification/_global/search/SearchResponse.ts
@@ -18,11 +18,16 @@
  */
 
 import { Aggregate } from '@_types/aggregations/Aggregate'
-import { AggregateName, Id, ScrollId, SuggestionName } from '@_types/common'
+import {
+  AggregateName,
+  Id,
+  ScrollId,
+  SuggestionName,
+  UserDefinedObject
+} from '@_types/common'
 import { double, long } from '@_types/Numeric'
 import { ClusterStatistics, ShardStatistics } from '@_types/Stats'
 import { Dictionary } from '@spec_utils/Dictionary'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 import { HitsMetadata } from './_types/hits'
 import { Profile } from './_types/profile'
 import { Suggest } from './_types/suggester'
@@ -68,7 +73,7 @@ export class ResponseBody<TDocument> {
   hits: HitsMetadata<TDocument>
   aggregations?: Dictionary<AggregateName, Aggregate>
   _clusters?: ClusterStatistics
-  fields?: Dictionary<string, UserDefinedValue>
+  fields?: UserDefinedObject
   max_score?: double
   num_reduce_phases?: long
   profile?: Profile
diff --git a/specification/_global/search/_types/hits.ts b/specification/_global/search/_types/hits.ts
index 17c7291618..9b513af9a3 100644
--- a/specification/_global/search/_types/hits.ts
+++ b/specification/_global/search/_types/hits.ts
@@ -24,6 +24,7 @@ import {
   IndexName,
   Name,
   SequenceNumber,
+  UserDefinedObject,
   VersionNumber
 } from '@_types/common'
 import { double, integer, long } from '@_types/Numeric'
@@ -49,7 +50,7 @@ export class Hit<TDocument> {
   // See https://github.com/elastic/elasticsearch-specification/pull/5248
   _score?: double | null
   _explanation?: Explanation
-  fields?: Dictionary<string, UserDefinedValue>
+  fields?: UserDefinedObject
   highlight?: Dictionary<string, string[]>
   inner_hits?: Dictionary<string, InnerHitsResult>
   matched_queries?: string[] | Dictionary<string, double>
diff --git a/specification/_global/search/_types/suggester.ts b/specification/_global/search/_types/suggester.ts
index 7dbbb7da99..6880e3e768 100644
--- a/specification/_global/search/_types/suggester.ts
+++ b/specification/_global/search/_types/suggester.ts
@@ -23,7 +23,8 @@ import {
   Id,
   IndexName,
   Routing,
-  SuggestMode
+  SuggestMode,
+  UserDefinedObject
 } from '@_types/common'
 import { GeoHashPrecision, GeoLocation } from '@_types/Geo'
 import { double, float, integer, long } from '@_types/Numeric'
@@ -74,7 +75,7 @@ export class TermSuggest extends SuggestBase {
 export class CompletionSuggestOption<TDocument> {
   collate_match?: boolean
   contexts?: Dictionary<string, Context[]>
-  fields?: Dictionary<string, UserDefinedValue>
+  fields?: UserDefinedObject
   _id?: string
   _index?: IndexName
   _routing?: Routing
diff --git a/specification/_global/search_template/SearchTemplateResponse.ts b/specification/_global/search_template/SearchTemplateResponse.ts
index ecc7d43e81..13b3eeaea1 100644
--- a/specification/_global/search_template/SearchTemplateResponse.ts
+++ b/specification/_global/search_template/SearchTemplateResponse.ts
@@ -18,14 +18,19 @@
  */
 
 import { Aggregate } from '@_types/aggregations/Aggregate'
-import { AggregateName, Id, ScrollId, SuggestionName } from '@_types/common'
+import {
+  AggregateName,
+  Id,
+  ScrollId,
+  SuggestionName,
+  UserDefinedObject
+} from '@_types/common'
 import { double, long } from '@_types/Numeric'
 import { ClusterStatistics, ShardStatistics } from '@_types/Stats'
 import { HitsMetadata } from '@global/search/_types/hits'
 import { Profile } from '@global/search/_types/profile'
 import { Suggest } from '@global/search/_types/suggester'
 import { Dictionary } from '@spec_utils/Dictionary'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
 export class Response<TDocument> {
   body: {
@@ -36,7 +41,7 @@ export class Response<TDocument> {
     hits: HitsMetadata<TDocument>
     aggregations?: Dictionary<AggregateName, Aggregate>
     _clusters?: ClusterStatistics
-    fields?: Dictionary<string, UserDefinedValue>
+    fields?: UserDefinedObject
     max_score?: double
     num_reduce_phases?: long
     profile?: Profile
diff --git a/specification/_types/common.ts b/specification/_types/common.ts
index 91155570d1..3990bfff44 100644
--- a/specification/_types/common.ts
+++ b/specification/_types/common.ts
@@ -92,6 +92,7 @@ export type DataStreamNames = DataStreamName | DataStreamName[]
 /** @doc_id byte-units */
 export type ByteSize = long | string
 
+export type UserDefinedObject = Dictionary<string, UserDefinedValue>
 export type Metadata = Dictionary<string, UserDefinedValue>
 
 // Versioning Numbers & Strings
@@ -328,7 +329,7 @@ export enum WaitForEvents {
 export class InlineGet<TDocument>
   implements AdditionalProperties<string, UserDefinedValue>
 {
-  fields?: Dictionary<string, UserDefinedValue>
+  fields?: UserDefinedObject
   found: boolean
   _seq_no?: SequenceNumber
   _primary_term?: long
diff --git a/specification/async_search/_types/AsyncSearch.ts b/specification/async_search/_types/AsyncSearch.ts
index e1e57dc754..57944a910e 100644
--- a/specification/async_search/_types/AsyncSearch.ts
+++ b/specification/async_search/_types/AsyncSearch.ts
@@ -18,14 +18,19 @@
  */
 
 import { Aggregate } from '@_types/aggregations/Aggregate'
-import { AggregateName, Id, ScrollId, SuggestionName } from '@_types/common'
+import {
+  AggregateName,
+  Id,
+  ScrollId,
+  SuggestionName,
+  UserDefinedObject
+} from '@_types/common'
 import { double, long } from '@_types/Numeric'
 import { ClusterStatistics, ShardStatistics } from '@_types/Stats'
 import { HitsMetadata } from '@global/search/_types/hits'
 import { Profile } from '@global/search/_types/profile'
 import { Suggest } from '@global/search/_types/suggester'
 import { Dictionary } from '@spec_utils/Dictionary'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
 export class AsyncSearch<TDocument> {
   /**
@@ -33,7 +38,7 @@ export class AsyncSearch<TDocument> {
    */
   aggregations?: Dictionary<AggregateName, Aggregate>
   _clusters?: ClusterStatistics
-  fields?: Dictionary<string, UserDefinedValue>
+  fields?: UserDefinedObject
   hits: HitsMetadata<TDocument>
   max_score?: double
   /**
diff --git a/specification/fleet/search/SearchResponse.ts b/specification/fleet/search/SearchResponse.ts
index e54d4b5907..bf42a9fad8 100644
--- a/specification/fleet/search/SearchResponse.ts
+++ b/specification/fleet/search/SearchResponse.ts
@@ -18,14 +18,19 @@
  */
 
 import { Aggregate } from '@_types/aggregations/Aggregate'
-import { AggregateName, Id, ScrollId, SuggestionName } from '@_types/common'
+import {
+  AggregateName,
+  Id,
+  ScrollId,
+  SuggestionName,
+  UserDefinedObject
+} from '@_types/common'
 import { double, long } from '@_types/Numeric'
 import { ClusterStatistics, ShardStatistics } from '@_types/Stats'
 import { HitsMetadata } from '@global/search/_types/hits'
 import { Profile } from '@global/search/_types/profile'
 import { Suggest } from '@global/search/_types/suggester'
 import { Dictionary } from '@spec_utils/Dictionary'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
 // Keep changes in sync with:
 // - search
@@ -38,7 +43,7 @@ export class Response<TDocument> {
     hits: HitsMetadata<TDocument>
     aggregations?: Dictionary<AggregateName, Aggregate>
     _clusters?: ClusterStatistics
-    fields?: Dictionary<string, UserDefinedValue>
+    fields?: UserDefinedObject
     max_score?: double
     num_reduce_phases?: long
     profile?: Profile
diff --git a/specification/ingest/_types/Simulation.ts b/specification/ingest/_types/Simulation.ts
index 12b3e00d84..6c9f3f424e 100644
--- a/specification/ingest/_types/Simulation.ts
+++ b/specification/ingest/_types/Simulation.ts
@@ -17,11 +17,17 @@
  * under the License.
  */
 
-import { Id, IndexName, Name, VersionNumber, VersionType } from '@_types/common'
+import {
+  Id,
+  IndexName,
+  Name,
+  UserDefinedObject,
+  VersionNumber,
+  VersionType
+} from '@_types/common'
 import { ErrorCause } from '@_types/Errors'
 import { DateTime } from '@_types/Time'
 import { AdditionalProperties } from '@spec_utils/behaviors'
-import { Dictionary } from '@spec_utils/Dictionary'
 import { Stringified } from '@spec_utils/Stringified'
 import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
@@ -106,7 +112,7 @@ export class DocumentSimulation
   /**
    * JSON body for the document.
    */
-  _source: Dictionary<string, UserDefinedValue>
+  _source: UserDefinedObject
   /**
    *
    */
diff --git a/specification/ml/infer_trained_model/MlInferTrainedModelRequest.ts b/specification/ml/infer_trained_model/MlInferTrainedModelRequest.ts
index d3dc96d86b..47bf793831 100644
--- a/specification/ml/infer_trained_model/MlInferTrainedModelRequest.ts
+++ b/specification/ml/infer_trained_model/MlInferTrainedModelRequest.ts
@@ -18,11 +18,9 @@
  */
 
 import { RequestBase } from '@_types/Base'
-import { Id } from '@_types/common'
+import { Id, UserDefinedObject } from '@_types/common'
 import { Duration } from '@_types/Time'
 import { InferenceConfigUpdateContainer } from '@ml/_types/inference'
-import { Dictionary } from '@spec_utils/Dictionary'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
 /**
  * Evaluate a trained model.
@@ -58,7 +56,7 @@ export interface Request extends RequestBase {
      * configured trained model input. Typically, for NLP models, the field name is `text_field`.
      * Currently, for NLP models, only a single value is allowed.
      */
-    docs: Dictionary<string, UserDefinedValue>[]
+    docs: UserDefinedObject[]
     /**
      * The inference configuration updates to apply on the API call
      */
diff --git a/specification/simulate/ingest/SimulateIngestResponse.ts b/specification/simulate/ingest/SimulateIngestResponse.ts
index 8252423078..d72f097da5 100644
--- a/specification/simulate/ingest/SimulateIngestResponse.ts
+++ b/specification/simulate/ingest/SimulateIngestResponse.ts
@@ -17,13 +17,12 @@
  * under the License.
  */
 
-import { Id, IndexName, VersionNumber } from '@_types/common'
+import { Id, IndexName, UserDefinedObject, VersionNumber } from '@_types/common'
 import { ErrorCause } from '@_types/Errors'
 import { TypeMapping } from '@_types/mapping/TypeMapping'
 import { AdditionalProperties } from '@spec_utils/behaviors'
 import { Dictionary } from '@spec_utils/Dictionary'
 import { Stringified } from '@spec_utils/Stringified'
-import { UserDefinedValue } from '@spec_utils/UserDefinedValue'
 
 export class Response {
   body: { docs: SimulateIngestDocumentResult[] }
@@ -55,7 +54,7 @@ export class IngestDocumentSimulation
   /**
    * JSON body for the document.
    */
-  _source: Dictionary<string, UserDefinedValue>
+  _source: UserDefinedObject
   /**
    *
    */