diff --git a/output/openapi/elasticsearch-openapi.json b/output/openapi/elasticsearch-openapi.json
index e81abafcaa..c1a09f1b40 100644
--- a/output/openapi/elasticsearch-openapi.json
+++ b/output/openapi/elasticsearch-openapi.json
@@ -109216,10 +109216,7 @@
               }
             ]
           }
-        },
-        "required": [
-          "vocabulary"
-        ]
+        }
       },
       "ml._types.LearningToRankConfig": {
         "type": "object",
@@ -109360,10 +109357,7 @@
               }
             ]
           }
-        },
-        "required": [
-          "vocabulary"
-        ]
+        }
       },
       "ml._types.TextExpansionInferenceOptions": {
         "description": "Text expansion inference options",
@@ -109388,10 +109382,7 @@
               }
             ]
           }
-        },
-        "required": [
-          "vocabulary"
-        ]
+        }
       },
       "ml._types.QuestionAnsweringInferenceOptions": {
         "description": "Question answering inference options",
diff --git a/output/openapi/elasticsearch-serverless-openapi.json b/output/openapi/elasticsearch-serverless-openapi.json
index 159b61d22f..cb8211c6bb 100644
--- a/output/openapi/elasticsearch-serverless-openapi.json
+++ b/output/openapi/elasticsearch-serverless-openapi.json
@@ -71791,10 +71791,7 @@
               }
             ]
           }
-        },
-        "required": [
-          "vocabulary"
-        ]
+        }
       },
       "ml._types.LearningToRankConfig": {
         "type": "object",
@@ -71935,10 +71932,7 @@
               }
             ]
           }
-        },
-        "required": [
-          "vocabulary"
-        ]
+        }
       },
       "ml._types.TextExpansionInferenceOptions": {
         "description": "Text expansion inference options",
@@ -71963,10 +71957,7 @@
               }
             ]
           }
-        },
-        "required": [
-          "vocabulary"
-        ]
+        }
       },
       "ml._types.QuestionAnsweringInferenceOptions": {
         "description": "Question answering inference options",
diff --git a/output/schema/schema.json b/output/schema/schema.json
index b41dc7b02a..920a2940ad 100644
--- a/output/schema/schema.json
+++ b/output/schema/schema.json
@@ -191376,7 +191376,7 @@
         },
         {
           "name": "vocabulary",
-          "required": true,
+          "required": false,
           "type": {
             "kind": "instance_of",
             "type": {
@@ -195481,7 +195481,7 @@
         },
         {
           "name": "vocabulary",
-          "required": true,
+          "required": false,
           "type": {
             "kind": "instance_of",
             "type": {
@@ -195560,7 +195560,7 @@
         },
         {
           "name": "vocabulary",
-          "required": true,
+          "required": false,
           "type": {
             "kind": "instance_of",
             "type": {
diff --git a/output/typescript/types.ts b/output/typescript/types.ts
index 15f6af5911..558e1e1723 100644
--- a/output/typescript/types.ts
+++ b/output/typescript/types.ts
@@ -16091,7 +16091,7 @@ export interface MlFillMaskInferenceOptions {
   num_top_classes?: integer
   tokenization?: MlTokenizationConfigContainer
   results_field?: string
-  vocabulary: MlVocabulary
+  vocabulary?: MlVocabulary
 }
 
 export interface MlFillMaskInferenceUpdateOptions {
@@ -16510,7 +16510,7 @@ export interface MlTextEmbeddingInferenceOptions {
   embedding_size?: integer
   tokenization?: MlTokenizationConfigContainer
   results_field?: string
-  vocabulary: MlVocabulary
+  vocabulary?: MlVocabulary
 }
 
 export interface MlTextEmbeddingInferenceUpdateOptions {
@@ -16521,7 +16521,7 @@ export interface MlTextEmbeddingInferenceUpdateOptions {
 export interface MlTextExpansionInferenceOptions {
   tokenization?: MlTokenizationConfigContainer
   results_field?: string
-  vocabulary: MlVocabulary
+  vocabulary?: MlVocabulary
 }
 
 export interface MlTextExpansionInferenceUpdateOptions {
diff --git a/specification/ml/_types/inference.ts b/specification/ml/_types/inference.ts
index 75aafa1f20..4f0c21caac 100644
--- a/specification/ml/_types/inference.ts
+++ b/specification/ml/_types/inference.ts
@@ -258,7 +258,7 @@ export class TextEmbeddingInferenceOptions {
   /** The field that is added to incoming documents to contain the inference prediction. Defaults to predicted_value. */
   results_field?: string
 
-  vocabulary: Vocabulary
+  vocabulary?: Vocabulary
 }
 
 /** Text expansion inference options */
@@ -267,7 +267,7 @@ export class TextExpansionInferenceOptions {
   tokenization?: TokenizationConfigContainer
   /** The field that is added to incoming documents to contain the inference prediction. Defaults to predicted_value. */
   results_field?: string
-  vocabulary: Vocabulary
+  vocabulary?: Vocabulary
 }
 
 /** Named entity recognition options */
@@ -295,7 +295,7 @@ export class FillMaskInferenceOptions {
   tokenization?: TokenizationConfigContainer
   /** The field that is added to incoming documents to contain the inference prediction. Defaults to predicted_value. */
   results_field?: string
-  vocabulary: Vocabulary
+  vocabulary?: Vocabulary
 }
 
 /** Question answering inference options */