diff --git a/output/openapi/elasticsearch-openapi.json b/output/openapi/elasticsearch-openapi.json
index 4a51b2a202..e81215c773 100644
--- a/output/openapi/elasticsearch-openapi.json
+++ b/output/openapi/elasticsearch-openapi.json
@@ -10596,7 +10596,7 @@
           {
             "in": "query",
             "name": "format",
-            "description": "A short version of the Accept header, for example `json` or `yaml`.",
+            "description": "A short version of the Accept header, e.g. json, yaml.\n\n`csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.\n\nFor async requests, nothing will be returned if the async query doesn't finish within the timeout.\nThe query ID and running status are available in the `X-Elasticsearch-Async-Id` and `X-Elasticsearch-Async-Is-Running` HTTP headers of the response, respectively.",
             "deprecated": false,
             "schema": {
               "$ref": "#/components/schemas/esql._types.EsqlFormat"
@@ -11013,7 +11013,7 @@
           {
             "in": "query",
             "name": "format",
-            "description": "A short version of the Accept header, e.g. json, yaml.",
+            "description": "A short version of the Accept header, e.g. json, yaml.\n\n`csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.",
             "deprecated": false,
             "schema": {
               "$ref": "#/components/schemas/esql._types.EsqlFormat"
@@ -83115,9 +83115,11 @@
             "type": "object",
             "properties": {
               "id": {
+                "description": "The ID of the async query, to be used in subsequent requests to check the status or retrieve results.\n\nAlso available in the `X-Elasticsearch-Async-Id` HTTP header.",
                 "type": "string"
               },
               "is_running": {
+                "description": "Indicates whether the async query is still running or has completed.\n\nAlso available in the `X-Elasticsearch-Async-Is-Running` HTTP header.",
                 "type": "boolean"
               }
             },
diff --git a/output/openapi/elasticsearch-serverless-openapi.json b/output/openapi/elasticsearch-serverless-openapi.json
index d16f747896..2e7af79da1 100644
--- a/output/openapi/elasticsearch-serverless-openapi.json
+++ b/output/openapi/elasticsearch-serverless-openapi.json
@@ -6235,7 +6235,7 @@
           {
             "in": "query",
             "name": "format",
-            "description": "A short version of the Accept header, e.g. json, yaml.",
+            "description": "A short version of the Accept header, e.g. json, yaml.\n\n`csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.",
             "deprecated": false,
             "schema": {
               "$ref": "#/components/schemas/esql._types.EsqlFormat"
diff --git a/output/schema/schema.json b/output/schema/schema.json
index 4a8fc859a4..eb1b95cf81 100644
--- a/output/schema/schema.json
+++ b/output/schema/schema.json
@@ -137189,6 +137189,7 @@
       },
       "properties": [
         {
+          "description": "The ID of the async query, to be used in subsequent requests to check the status or retrieve results.\n\nAlso available in the `X-Elasticsearch-Async-Id` HTTP header.",
           "name": "id",
           "required": false,
           "type": {
@@ -137200,6 +137201,7 @@
           }
         },
         {
+          "description": "Indicates whether the async query is still running or has completed.\n\nAlso available in the `X-Elasticsearch-Async-Is-Running` HTTP header.",
           "name": "is_running",
           "required": true,
           "type": {
@@ -137211,7 +137213,7 @@
           }
         }
       ],
-      "specLocation": "esql/_types/EsqlResult.ts#L45-L48"
+      "specLocation": "esql/_types/EsqlResult.ts#L45-L58"
     },
     {
       "kind": "interface",
@@ -137288,7 +137290,7 @@
           }
         }
       ],
-      "specLocation": "esql/_types/EsqlResult.ts#L65-L71"
+      "specLocation": "esql/_types/EsqlResult.ts#L75-L81"
     },
     {
       "kind": "interface",
@@ -137386,7 +137388,7 @@
           }
         }
       ],
-      "specLocation": "esql/_types/EsqlResult.ts#L55-L63"
+      "specLocation": "esql/_types/EsqlResult.ts#L65-L73"
     },
     {
       "kind": "enum",
@@ -137411,7 +137413,7 @@
         "name": "EsqlClusterStatus",
         "namespace": "esql._types"
       },
-      "specLocation": "esql/_types/EsqlResult.ts#L73-L79"
+      "specLocation": "esql/_types/EsqlResult.ts#L83-L89"
     },
     {
       "kind": "interface",
@@ -137443,7 +137445,7 @@
           }
         }
       ],
-      "specLocation": "esql/_types/EsqlResult.ts#L50-L53"
+      "specLocation": "esql/_types/EsqlResult.ts#L60-L63"
     },
     {
       "kind": "enum",
@@ -137649,7 +137651,7 @@
           }
         }
       ],
-      "specLocation": "esql/_types/EsqlResult.ts#L88-L93"
+      "specLocation": "esql/_types/EsqlResult.ts#L98-L103"
     },
     {
       "kind": "interface",
@@ -137703,7 +137705,7 @@
           }
         }
       ],
-      "specLocation": "esql/_types/EsqlResult.ts#L81-L86"
+      "specLocation": "esql/_types/EsqlResult.ts#L91-L96"
     },
     {
       "kind": "interface",
@@ -138146,7 +138148,7 @@
           }
         },
         {
-          "description": "A short version of the Accept header, for example `json` or `yaml`.",
+          "description": "A short version of the Accept header, e.g. json, yaml.\n\n`csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.\n\nFor async requests, nothing will be returned if the async query doesn't finish within the timeout.\nThe query ID and running status are available in the `X-Elasticsearch-Async-Id` and `X-Elasticsearch-Async-Is-Running` HTTP headers of the response, respectively.",
           "name": "format",
           "required": false,
           "type": {
@@ -138158,7 +138160,7 @@
           }
         }
       ],
-      "specLocation": "esql/async_query/AsyncQueryRequest.ts#L28-L133"
+      "specLocation": "esql/async_query/AsyncQueryRequest.ts#L28-L138"
     },
     {
       "kind": "response",
@@ -138921,7 +138923,7 @@
       "path": [],
       "query": [
         {
-          "description": "A short version of the Accept header, e.g. json, yaml.",
+          "description": "A short version of the Accept header, e.g. json, yaml.\n\n`csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.",
           "name": "format",
           "required": false,
           "type": {
@@ -138971,7 +138973,7 @@
           }
         }
       ],
-      "specLocation": "esql/query/QueryRequest.ts#L27-L113"
+      "specLocation": "esql/query/QueryRequest.ts#L27-L115"
     },
     {
       "kind": "response",
diff --git a/specification/esql/_types/EsqlResult.ts b/specification/esql/_types/EsqlResult.ts
index 649e323d2b..b3d37ed3f9 100644
--- a/specification/esql/_types/EsqlResult.ts
+++ b/specification/esql/_types/EsqlResult.ts
@@ -43,7 +43,17 @@ export class EsqlResult {
 }
 
 export class AsyncEsqlResult extends EsqlResult {
+  /**
+   * The ID of the async query, to be used in subsequent requests to check the status or retrieve results.
+   *
+   * Also available in the `X-Elasticsearch-Async-Id` HTTP header.
+   */
   id?: string
+  /**
+   * Indicates whether the async query is still running or has completed.
+   *
+   * Also available in the `X-Elasticsearch-Async-Is-Running` HTTP header.
+   */
   is_running: boolean
 }
 
diff --git a/specification/esql/async_query/AsyncQueryRequest.ts b/specification/esql/async_query/AsyncQueryRequest.ts
index f14574f1c4..87709cef94 100644
--- a/specification/esql/async_query/AsyncQueryRequest.ts
+++ b/specification/esql/async_query/AsyncQueryRequest.ts
@@ -58,7 +58,12 @@ export interface Request extends RequestBase {
      */
     drop_null_columns?: boolean
     /**
-     * A short version of the Accept header, for example `json` or `yaml`.
+     * A short version of the Accept header, e.g. json, yaml.
+     *
+     * `csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.
+     *
+     * For async requests, nothing will be returned if the async query doesn't finish within the timeout.
+     * The query ID and running status are available in the `X-Elasticsearch-Async-Id` and `X-Elasticsearch-Async-Is-Running` HTTP headers of the response, respectively.
      */
     format?: EsqlFormat
   }
diff --git a/specification/esql/query/QueryRequest.ts b/specification/esql/query/QueryRequest.ts
index 735974d5e1..91004d2312 100644
--- a/specification/esql/query/QueryRequest.ts
+++ b/specification/esql/query/QueryRequest.ts
@@ -43,6 +43,8 @@ export interface Request extends RequestBase {
   query_parameters: {
     /**
      * A short version of the Accept header, e.g. json, yaml.
+     *
+     * `csv`, `tsv`, and `txt` formats will return results in a tabular format, excluding other metadata fields from the response.
      */
     format?: EsqlFormat
     /**