diff --git a/specification/_global/msearch/MultiSearchRequest.ts b/specification/_global/msearch/MultiSearchRequest.ts
index 888b94ffba..273b0f82b4 100644
--- a/specification/_global/msearch/MultiSearchRequest.ts
+++ b/specification/_global/msearch/MultiSearchRequest.ts
@@ -83,6 +83,7 @@ export interface Request extends RequestBase {
     ccs_minimize_roundtrips?: boolean
     /**
      * Type of index that wildcard expressions can match. If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
+     * @server_default open
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/_global/rank_eval/RankEvalRequest.ts b/specification/_global/rank_eval/RankEvalRequest.ts
index 4e63e4ea0c..56ff06a8e2 100644
--- a/specification/_global/rank_eval/RankEvalRequest.ts
+++ b/specification/_global/rank_eval/RankEvalRequest.ts
@@ -57,6 +57,9 @@ export interface Request extends RequestBase {
      * @server_default true
      */
     allow_no_indices?: boolean
+    /**
+     * @server_default open
+     */
     expand_wildcards?: ExpandWildcards
     /**
      * If `true`, missing or closed indices are not included in the response.
diff --git a/specification/_global/search_template/SearchTemplateRequest.ts b/specification/_global/search_template/SearchTemplateRequest.ts
index fd4772cd50..3e23fa9f3b 100644
--- a/specification/_global/search_template/SearchTemplateRequest.ts
+++ b/specification/_global/search_template/SearchTemplateRequest.ts
@@ -75,6 +75,7 @@ export interface Request extends RequestBase {
      * The type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * Supports comma-separated values, such as `open,hidden`.
+     * @server_default open
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/_global/update_by_query/UpdateByQueryRequest.ts b/specification/_global/update_by_query/UpdateByQueryRequest.ts
index e9713260ea..ffabc80fce 100644
--- a/specification/_global/update_by_query/UpdateByQueryRequest.ts
+++ b/specification/_global/update_by_query/UpdateByQueryRequest.ts
@@ -190,6 +190,7 @@ export interface Request extends RequestBase {
      * The type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * It supports comma-separated values, such as `open,hidden`.
+     * @server_default open
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/async_search/submit/AsyncSearchSubmitRequest.ts b/specification/async_search/submit/AsyncSearchSubmitRequest.ts
index a4e2d88ee6..faaa98f380 100644
--- a/specification/async_search/submit/AsyncSearchSubmitRequest.ts
+++ b/specification/async_search/submit/AsyncSearchSubmitRequest.ts
@@ -126,6 +126,9 @@ export interface Request extends RequestBase {
     default_operator?: Operator
     df?: string
     docvalue_fields?: Fields
+    /**
+     * @server_default open
+     */
     expand_wildcards?: ExpandWildcards
     explain?: boolean
     ignore_throttled?: boolean
diff --git a/specification/cat/aliases/CatAliasesRequest.ts b/specification/cat/aliases/CatAliasesRequest.ts
index 60621f23e2..d8aa713f15 100644
--- a/specification/cat/aliases/CatAliasesRequest.ts
+++ b/specification/cat/aliases/CatAliasesRequest.ts
@@ -64,6 +64,7 @@ export interface Request extends CatRequestBase {
      * The type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * It supports comma-separated values, such as `open,hidden`.
+     * @server_default all
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/cat/indices/CatIndicesRequest.ts b/specification/cat/indices/CatIndicesRequest.ts
index f0f181d1b2..ade33c72a3 100644
--- a/specification/cat/indices/CatIndicesRequest.ts
+++ b/specification/cat/indices/CatIndicesRequest.ts
@@ -66,6 +66,7 @@ export interface Request extends CatRequestBase {
   query_parameters: {
     /**
      * The type of index that wildcard patterns can match.
+     * @server_default all
      */
     expand_wildcards?: ExpandWildcards
     /** The health status used to limit returned indices. By default, the response includes indices of any health status. */
diff --git a/specification/cluster/health/ClusterHealthRequest.ts b/specification/cluster/health/ClusterHealthRequest.ts
index 083cf0b746..23b5cd83d5 100644
--- a/specification/cluster/health/ClusterHealthRequest.ts
+++ b/specification/cluster/health/ClusterHealthRequest.ts
@@ -66,6 +66,9 @@ export interface Request extends RequestBase {
     index?: Indices
   }
   query_parameters: {
+    /**
+     * @server_default all
+     */
     expand_wildcards?: ExpandWildcards
     /**
      * Can be one of cluster, indices or shards. Controls the details level of the health information returned.
diff --git a/specification/cluster/state/ClusterStateRequest.ts b/specification/cluster/state/ClusterStateRequest.ts
index 29772d76eb..a3c1efc48d 100644
--- a/specification/cluster/state/ClusterStateRequest.ts
+++ b/specification/cluster/state/ClusterStateRequest.ts
@@ -74,6 +74,7 @@ export interface Request extends RequestBase {
   query_parameters: {
     /** @server_default true */
     allow_no_indices?: boolean
+    /** @server_default open */
     expand_wildcards?: ExpandWildcards
     /** @server_default false */
     flat_settings?: boolean
diff --git a/specification/indices/data_streams_stats/IndicesDataStreamsStatsRequest.ts b/specification/indices/data_streams_stats/IndicesDataStreamsStatsRequest.ts
index ec064fcd60..9c64c7172b 100644
--- a/specification/indices/data_streams_stats/IndicesDataStreamsStatsRequest.ts
+++ b/specification/indices/data_streams_stats/IndicesDataStreamsStatsRequest.ts
@@ -54,7 +54,7 @@ export interface Request extends RequestBase {
     /**
      * Type of data stream that wildcard patterns can match.
      * Supports comma-separated values, such as `open,hidden`.
-     * @server_default open
+     * @server_default open,closed
      */
     expand_wildcards?: ExpandWildcards
   }
diff --git a/specification/indices/delete/IndicesDeleteRequest.ts b/specification/indices/delete/IndicesDeleteRequest.ts
index 7110ecc718..b2a93c570b 100644
--- a/specification/indices/delete/IndicesDeleteRequest.ts
+++ b/specification/indices/delete/IndicesDeleteRequest.ts
@@ -62,7 +62,7 @@ export interface Request extends RequestBase {
      * Type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * Supports comma-separated values, such as `open,hidden`.
-     * @server_default open
+     * @server_default open,closed
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/indices/delete_data_lifecycle/IndicesDeleteDataLifecycleRequest.ts b/specification/indices/delete_data_lifecycle/IndicesDeleteDataLifecycleRequest.ts
index a25a66257d..fe4c72e305 100644
--- a/specification/indices/delete_data_lifecycle/IndicesDeleteDataLifecycleRequest.ts
+++ b/specification/indices/delete_data_lifecycle/IndicesDeleteDataLifecycleRequest.ts
@@ -41,6 +41,9 @@ export interface Request extends RequestBase {
     name: DataStreamNames
   }
   query_parameters: {
+    /**
+     * @server_default open
+     */
     expand_wildcards?: ExpandWildcards
     /**
      * @server_default 30s
diff --git a/specification/indices/delete_data_stream_options/IndicesDeleteDataStreamOptionsRequest.ts b/specification/indices/delete_data_stream_options/IndicesDeleteDataStreamOptionsRequest.ts
index e53b07423e..e133bb60b2 100644
--- a/specification/indices/delete_data_stream_options/IndicesDeleteDataStreamOptionsRequest.ts
+++ b/specification/indices/delete_data_stream_options/IndicesDeleteDataStreamOptionsRequest.ts
@@ -41,6 +41,9 @@ export interface Request extends RequestBase {
     name: DataStreamNames
   }
   query_parameters: {
+    /**
+     * @server_default open
+     */
     expand_wildcards?: ExpandWildcards
     /**
      * @server_default 30s
diff --git a/specification/indices/exists_alias/IndicesExistsAliasRequest.ts b/specification/indices/exists_alias/IndicesExistsAliasRequest.ts
index c80e57e664..7a16e005b3 100644
--- a/specification/indices/exists_alias/IndicesExistsAliasRequest.ts
+++ b/specification/indices/exists_alias/IndicesExistsAliasRequest.ts
@@ -63,7 +63,7 @@ export interface Request extends RequestBase {
      * Type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * Supports comma-separated values, such as `open,hidden`.
-     * @server_default open
+     * @server_default all
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/indices/field_usage_stats/IndicesFieldUsageStatsRequest.ts b/specification/indices/field_usage_stats/IndicesFieldUsageStatsRequest.ts
index 194cc10971..dac6f9f1ce 100644
--- a/specification/indices/field_usage_stats/IndicesFieldUsageStatsRequest.ts
+++ b/specification/indices/field_usage_stats/IndicesFieldUsageStatsRequest.ts
@@ -58,6 +58,7 @@ export interface Request extends RequestBase {
      * Type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * Supports comma-separated values, such as `open,hidden`.
+     * @server_default open
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/indices/forcemerge/IndicesForceMergeRequest.ts b/specification/indices/forcemerge/IndicesForceMergeRequest.ts
index d18a6a4adc..108db6fe4f 100644
--- a/specification/indices/forcemerge/IndicesForceMergeRequest.ts
+++ b/specification/indices/forcemerge/IndicesForceMergeRequest.ts
@@ -98,6 +98,9 @@ export interface Request extends RequestBase {
   }
   query_parameters: {
     allow_no_indices?: boolean
+    /**
+     * @server_default open
+     */
     expand_wildcards?: ExpandWildcards
     flush?: boolean
     ignore_unavailable?: boolean
diff --git a/specification/indices/get_alias/IndicesGetAliasRequest.ts b/specification/indices/get_alias/IndicesGetAliasRequest.ts
index e1983efd20..79b7833ca2 100644
--- a/specification/indices/get_alias/IndicesGetAliasRequest.ts
+++ b/specification/indices/get_alias/IndicesGetAliasRequest.ts
@@ -74,7 +74,7 @@ export interface Request extends RequestBase {
      * Type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * Supports comma-separated values, such as `open,hidden`.
-     * @server_default open
+     * @server_default all
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/indices/open/IndicesOpenRequest.ts b/specification/indices/open/IndicesOpenRequest.ts
index 9396761be4..bb0ebc3be8 100644
--- a/specification/indices/open/IndicesOpenRequest.ts
+++ b/specification/indices/open/IndicesOpenRequest.ts
@@ -80,7 +80,7 @@ export interface Request extends RequestBase {
      * Type of index that wildcard patterns can match.
      * If the request can target data streams, this argument determines whether wildcard expressions match hidden data streams.
      * Supports comma-separated values, such as `open,hidden`.
-     * @server_default open
+     * @server_default closed
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/indices/reload_search_analyzers/ReloadSearchAnalyzersRequest.ts b/specification/indices/reload_search_analyzers/ReloadSearchAnalyzersRequest.ts
index aa65f94951..5bab1b32f8 100644
--- a/specification/indices/reload_search_analyzers/ReloadSearchAnalyzersRequest.ts
+++ b/specification/indices/reload_search_analyzers/ReloadSearchAnalyzersRequest.ts
@@ -53,6 +53,7 @@ export interface Request extends RequestBase {
   }
   query_parameters: {
     allow_no_indices?: boolean
+    /** @server_default open */
     expand_wildcards?: ExpandWildcards
     ignore_unavailable?: boolean
     /**
diff --git a/specification/indices/stats/IndicesStatsRequest.ts b/specification/indices/stats/IndicesStatsRequest.ts
index b5d32d11ec..2ccb72d094 100644
--- a/specification/indices/stats/IndicesStatsRequest.ts
+++ b/specification/indices/stats/IndicesStatsRequest.ts
@@ -76,6 +76,7 @@ export interface Request extends RequestBase {
      * Type of index that wildcard patterns can match. If the request can target data streams, this argument
      * determines whether wildcard expressions match hidden data streams. Supports comma-separated values,
      * such as `open,hidden`.
+     * @server_default open
      */
     expand_wildcards?: ExpandWildcards
     /**
diff --git a/specification/searchable_snapshots/clear_cache/SearchableSnapshotsClearCacheRequest.ts b/specification/searchable_snapshots/clear_cache/SearchableSnapshotsClearCacheRequest.ts
index 52fe3ae85d..975650e1bd 100644
--- a/specification/searchable_snapshots/clear_cache/SearchableSnapshotsClearCacheRequest.ts
+++ b/specification/searchable_snapshots/clear_cache/SearchableSnapshotsClearCacheRequest.ts
@@ -49,6 +49,7 @@ export interface Request extends RequestBase {
     index?: Indices
   }
   query_parameters: {
+    /** @server_default open */
     expand_wildcards?: ExpandWildcards
     allow_no_indices?: boolean
     ignore_unavailable?: boolean