diff --git a/output/openapi/elasticsearch-openapi.json b/output/openapi/elasticsearch-openapi.json
index 619db3f0ee..d11a8eb980 100644
--- a/output/openapi/elasticsearch-openapi.json
+++ b/output/openapi/elasticsearch-openapi.json
@@ -17565,6 +17565,161 @@
         "x-state": "Added in 1.3.0"
       }
     },
+    "/_migration/reindex/{index}/_cancel": {
+      "post": {
+        "tags": [
+          "cancel_reindex"
+        ],
+        "summary": "This API cancels a migration reindex attempt for a data stream or index",
+        "operationId": "migrate-cancel-reindex",
+        "parameters": [
+          {
+            "in": "path",
+            "name": "index",
+            "description": "The index or data stream name",
+            "required": true,
+            "deprecated": false,
+            "schema": {
+              "$ref": "#/components/schemas/_types:Indices"
+            },
+            "style": "simple"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/_types:AcknowledgedResponseBase"
+                }
+              }
+            }
+          }
+        },
+        "x-state": "Technical preview"
+      }
+    },
+    "/_create_from/{source}/{dest}": {
+      "put": {
+        "tags": [
+          "create_from"
+        ],
+        "summary": "This API creates a destination from a source index",
+        "description": "It copies the mappings and settings from the source index while allowing request settings and mappings to override the source values.",
+        "operationId": "migrate-create-from",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/migrate.create_from#source"
+          },
+          {
+            "$ref": "#/components/parameters/migrate.create_from#dest"
+          }
+        ],
+        "requestBody": {
+          "$ref": "#/components/requestBodies/migrate.create_from"
+        },
+        "responses": {
+          "200": {
+            "$ref": "#/components/responses/migrate.create_from#200"
+          }
+        },
+        "x-state": "Technical preview"
+      },
+      "post": {
+        "tags": [
+          "create_from"
+        ],
+        "summary": "This API creates a destination from a source index",
+        "description": "It copies the mappings and settings from the source index while allowing request settings and mappings to override the source values.",
+        "operationId": "migrate-create-from-1",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/migrate.create_from#source"
+          },
+          {
+            "$ref": "#/components/parameters/migrate.create_from#dest"
+          }
+        ],
+        "requestBody": {
+          "$ref": "#/components/requestBodies/migrate.create_from"
+        },
+        "responses": {
+          "200": {
+            "$ref": "#/components/responses/migrate.create_from#200"
+          }
+        },
+        "x-state": "Technical preview"
+      }
+    },
+    "/_migration/reindex/{index}/_status": {
+      "get": {
+        "tags": [
+          "get_reindex_status"
+        ],
+        "summary": "This API returns the status of a migration reindex attempt for a data stream or index",
+        "operationId": "migrate-get-reindex-status",
+        "parameters": [
+          {
+            "in": "path",
+            "name": "index",
+            "description": "The index or data stream name",
+            "required": true,
+            "deprecated": false,
+            "schema": {
+              "$ref": "#/components/schemas/_types:Indices"
+            },
+            "style": "simple"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/_types:AcknowledgedResponseBase"
+                }
+              }
+            }
+          }
+        },
+        "x-state": "Technical preview"
+      }
+    },
+    "/_migration/reindex": {
+      "post": {
+        "tags": [
+          "reindex"
+        ],
+        "summary": "\"This API reindexes all legacy backing indices for a data stream",
+        "description": "It does this in a persistent task. The persistent task id is returned immediately, and the reindexing work is completed in that task",
+        "operationId": "migrate-reindex",
+        "requestBody": {
+          "content": {
+            "application/json": {
+              "schema": {
+                "$ref": "#/components/schemas/migrate._types:MigrateReindex"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/_types:AcknowledgedResponseBase"
+                }
+              }
+            }
+          }
+        },
+        "x-state": "Technical preview"
+      }
+    },
     "/_migration/deprecations": {
       "get": {
         "tags": [
@@ -75382,6 +75537,44 @@
           "_index"
         ]
       },
+      "migrate._types:CreateFrom": {
+        "type": "object",
+        "properties": {
+          "mappings_override": {
+            "$ref": "#/components/schemas/_types.mapping:TypeMapping"
+          },
+          "settings_override": {
+            "$ref": "#/components/schemas/indices._types:IndexSettings"
+          }
+        }
+      },
+      "migrate._types:MigrateReindex": {
+        "type": "object",
+        "properties": {
+          "mode": {
+            "description": "Reindex mode. Currently only 'upgrade' is supported.",
+            "type": "string"
+          },
+          "source": {
+            "$ref": "#/components/schemas/migrate._types:Index"
+          }
+        },
+        "required": [
+          "mode",
+          "source"
+        ]
+      },
+      "migrate._types:Index": {
+        "type": "object",
+        "properties": {
+          "index": {
+            "$ref": "#/components/schemas/_types:Indices"
+          }
+        },
+        "required": [
+          "index"
+        ]
+      },
       "migration.deprecations:Deprecation": {
         "type": "object",
         "properties": {
@@ -94366,6 +94559,32 @@
           }
         }
       },
+      "migrate.create_from#200": {
+        "description": "",
+        "content": {
+          "application/json": {
+            "schema": {
+              "type": "object",
+              "properties": {
+                "acknowledged": {
+                  "type": "boolean"
+                },
+                "index": {
+                  "$ref": "#/components/schemas/_types:IndexName"
+                },
+                "shards_acknowledged": {
+                  "type": "boolean"
+                }
+              },
+              "required": [
+                "acknowledged",
+                "index",
+                "shards_acknowledged"
+              ]
+            }
+          }
+        }
+      },
       "migration.deprecations#200": {
         "description": "",
         "content": {
@@ -101906,6 +102125,28 @@
         },
         "style": "form"
       },
+      "migrate.create_from#source": {
+        "in": "path",
+        "name": "source",
+        "description": "The source index or data stream name",
+        "required": true,
+        "deprecated": false,
+        "schema": {
+          "type": "string"
+        },
+        "style": "simple"
+      },
+      "migrate.create_from#dest": {
+        "in": "path",
+        "name": "dest",
+        "description": "The destination index or data stream name",
+        "required": true,
+        "deprecated": false,
+        "schema": {
+          "type": "string"
+        },
+        "style": "simple"
+      },
       "migration.deprecations#index": {
         "in": "path",
         "name": "index",
@@ -107361,6 +107602,16 @@
         },
         "required": true
       },
+      "migrate.create_from": {
+        "content": {
+          "application/json": {
+            "schema": {
+              "$ref": "#/components/schemas/migrate._types:CreateFrom"
+            }
+          }
+        },
+        "required": true
+      },
       "ml.delete_expired_data": {
         "content": {
           "application/json": {
diff --git a/output/schema/schema.json b/output/schema/schema.json
index 8fa956c181..1851429ad2 100644
--- a/output/schema/schema.json
+++ b/output/schema/schema.json
@@ -9898,6 +9898,163 @@
         }
       ]
     },
+    {
+      "availability": {
+        "serverless": {
+          "stability": "experimental",
+          "visibility": "private"
+        },
+        "stack": {
+          "since": "8.18.0",
+          "stability": "experimental"
+        }
+      },
+      "description": "This API cancels a migration reindex attempt for a data stream or index",
+      "docId": "migrate",
+      "docTag": "cancel_reindex",
+      "docUrl": "https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migrate-data-stream.html",
+      "name": "migrate.cancel_reindex",
+      "request": {
+        "name": "Request",
+        "namespace": "migrate.cancel_reindex"
+      },
+      "requestBodyRequired": false,
+      "requestMediaType": [
+        "application/json"
+      ],
+      "response": {
+        "name": "Response",
+        "namespace": "migrate.cancel_reindex"
+      },
+      "responseMediaType": [
+        "application/json"
+      ],
+      "urls": [
+        {
+          "methods": [
+            "POST"
+          ],
+          "path": "/_migration/reindex/{index}/_cancel"
+        }
+      ]
+    },
+    {
+      "availability": {
+        "serverless": {
+          "stability": "experimental",
+          "visibility": "private"
+        },
+        "stack": {
+          "since": "8.18.0",
+          "stability": "experimental"
+        }
+      },
+      "description": "This API creates a destination from a source index. It copies the mappings and settings from the source index while allowing request settings and mappings to override the source values.",
+      "docId": "migrate",
+      "docTag": "create_from",
+      "docUrl": "https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migrate-data-stream.html",
+      "name": "migrate.create_from",
+      "request": {
+        "name": "Request",
+        "namespace": "migrate.create_from"
+      },
+      "requestBodyRequired": true,
+      "requestMediaType": [
+        "application/json"
+      ],
+      "response": {
+        "name": "Response",
+        "namespace": "migrate.create_from"
+      },
+      "responseMediaType": [
+        "application/json"
+      ],
+      "urls": [
+        {
+          "methods": [
+            "PUT",
+            "POST"
+          ],
+          "path": "/_create_from/{source}/{dest}"
+        }
+      ]
+    },
+    {
+      "availability": {
+        "serverless": {
+          "stability": "experimental",
+          "visibility": "private"
+        },
+        "stack": {
+          "since": "8.18.0",
+          "stability": "experimental"
+        }
+      },
+      "description": "This API returns the status of a migration reindex attempt for a data stream or index",
+      "docId": "migrate",
+      "docTag": "get_reindex_status",
+      "docUrl": "https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migrate-data-stream.html",
+      "name": "migrate.get_reindex_status",
+      "request": {
+        "name": "Request",
+        "namespace": "migrate.get_reindex_status"
+      },
+      "requestBodyRequired": false,
+      "requestMediaType": [
+        "application/json"
+      ],
+      "response": {
+        "name": "Response",
+        "namespace": "migrate.get_reindex_status"
+      },
+      "responseMediaType": [
+        "application/json"
+      ],
+      "urls": [
+        {
+          "methods": [
+            "GET"
+          ],
+          "path": "/_migration/reindex/{index}/_status"
+        }
+      ]
+    },
+    {
+      "availability": {
+        "stack": {
+          "since": "8.18.0",
+          "stability": "experimental"
+        }
+      },
+      "description": "\"This API reindexes all legacy backing indices for a data stream. It does this in a persistent task. The persistent task id is returned immediately, and the reindexing work is completed in that task",
+      "docId": "migrate",
+      "docTag": "reindex",
+      "docUrl": "https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migrate-data-stream.html",
+      "name": "migrate.reindex",
+      "request": {
+        "name": "Request",
+        "namespace": "migrate.reindex"
+      },
+      "requestBodyRequired": true,
+      "requestMediaType": [
+        "application/json"
+      ],
+      "response": {
+        "name": "Response",
+        "namespace": "migrate.reindex"
+      },
+      "responseMediaType": [
+        "application/json"
+      ],
+      "urls": [
+        {
+          "methods": [
+            "POST"
+          ],
+          "path": "/_migration/reindex"
+        }
+      ]
+    },
     {
       "availability": {
         "stack": {
@@ -152776,6 +152933,354 @@
       },
       "specLocation": "logstash/put_pipeline/LogstashPutPipelineResponse.ts#L22-L24"
     },
+    {
+      "kind": "interface",
+      "name": {
+        "name": "CreateFrom",
+        "namespace": "migrate._types"
+      },
+      "properties": [
+        {
+          "description": "Mappings overrides to be applied to the destination index (optional)",
+          "name": "mappings_override",
+          "required": false,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "TypeMapping",
+              "namespace": "_types.mapping"
+            }
+          }
+        },
+        {
+          "description": "Settings overrides to be applied to the destination index (optional)",
+          "name": "settings_override",
+          "required": false,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "IndexSettings",
+              "namespace": "indices._types"
+            }
+          }
+        }
+      ],
+      "specLocation": "migrate/_types/CreateFrom.ts#L23-L32"
+    },
+    {
+      "kind": "interface",
+      "name": {
+        "name": "Index",
+        "namespace": "migrate._types"
+      },
+      "properties": [
+        {
+          "name": "index",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "Indices",
+              "namespace": "_types"
+            }
+          }
+        }
+      ],
+      "specLocation": "migrate/_types/MigrateReindex.ts#L33-L35"
+    },
+    {
+      "kind": "interface",
+      "name": {
+        "name": "MigrateReindex",
+        "namespace": "migrate._types"
+      },
+      "properties": [
+        {
+          "description": "Reindex mode. Currently only 'upgrade' is supported.",
+          "name": "mode",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "string",
+              "namespace": "_builtins"
+            }
+          }
+        },
+        {
+          "description": "The source index or data stream (only data streams are currently supported).",
+          "name": "source",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "Index",
+              "namespace": "migrate._types"
+            }
+          }
+        }
+      ],
+      "specLocation": "migrate/_types/MigrateReindex.ts#L22-L31"
+    },
+    {
+      "kind": "request",
+      "attachedBehaviors": [
+        "CommonQueryParameters"
+      ],
+      "body": {
+        "kind": "no_body"
+      },
+      "description": "This API cancels a migration reindex attempt for a data stream or index",
+      "inherits": {
+        "type": {
+          "name": "RequestBase",
+          "namespace": "_types"
+        }
+      },
+      "name": {
+        "name": "Request",
+        "namespace": "migrate.cancel_reindex"
+      },
+      "path": [
+        {
+          "description": "The index or data stream name",
+          "name": "index",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "Indices",
+              "namespace": "_types"
+            }
+          }
+        }
+      ],
+      "query": [],
+      "specLocation": "migrate/cancel_reindex/MigrateCancelReindexRequest.ts#L23-L37"
+    },
+    {
+      "kind": "response",
+      "body": {
+        "kind": "value",
+        "value": {
+          "kind": "instance_of",
+          "type": {
+            "name": "AcknowledgedResponseBase",
+            "namespace": "_types"
+          }
+        }
+      },
+      "name": {
+        "name": "Response",
+        "namespace": "migrate.cancel_reindex"
+      },
+      "specLocation": "migrate/cancel_reindex/MigrateCancelReindexResponse.ts#L22-L24"
+    },
+    {
+      "kind": "request",
+      "attachedBehaviors": [
+        "CommonQueryParameters"
+      ],
+      "body": {
+        "kind": "value",
+        "codegenName": "create_from",
+        "value": {
+          "kind": "instance_of",
+          "type": {
+            "name": "CreateFrom",
+            "namespace": "migrate._types"
+          }
+        }
+      },
+      "description": "This API creates a destination from a source index. It copies the mappings and settings from the source index while allowing request settings and mappings to override the source values.",
+      "inherits": {
+        "type": {
+          "name": "RequestBase",
+          "namespace": "_types"
+        }
+      },
+      "name": {
+        "name": "Request",
+        "namespace": "migrate.create_from"
+      },
+      "path": [
+        {
+          "description": "The source index or data stream name",
+          "name": "source",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "string",
+              "namespace": "_builtins"
+            }
+          }
+        },
+        {
+          "description": "The destination index or data stream name",
+          "name": "dest",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "string",
+              "namespace": "_builtins"
+            }
+          }
+        }
+      ],
+      "query": [],
+      "specLocation": "migrate/create_from/MigrateCreateFromRequest.ts#L23-L41"
+    },
+    {
+      "kind": "response",
+      "body": {
+        "kind": "properties",
+        "properties": [
+          {
+            "name": "acknowledged",
+            "required": true,
+            "type": {
+              "kind": "instance_of",
+              "type": {
+                "name": "boolean",
+                "namespace": "_builtins"
+              }
+            }
+          },
+          {
+            "name": "index",
+            "required": true,
+            "type": {
+              "kind": "instance_of",
+              "type": {
+                "name": "IndexName",
+                "namespace": "_types"
+              }
+            }
+          },
+          {
+            "name": "shards_acknowledged",
+            "required": true,
+            "type": {
+              "kind": "instance_of",
+              "type": {
+                "name": "boolean",
+                "namespace": "_builtins"
+              }
+            }
+          }
+        ]
+      },
+      "name": {
+        "name": "Response",
+        "namespace": "migrate.create_from"
+      },
+      "specLocation": "migrate/create_from/MigrateCreateFromResponse.ts#L22-L28"
+    },
+    {
+      "kind": "request",
+      "attachedBehaviors": [
+        "CommonQueryParameters"
+      ],
+      "body": {
+        "kind": "no_body"
+      },
+      "description": "This API returns the status of a migration reindex attempt for a data stream or index",
+      "inherits": {
+        "type": {
+          "name": "RequestBase",
+          "namespace": "_types"
+        }
+      },
+      "name": {
+        "name": "Request",
+        "namespace": "migrate.get_reindex_status"
+      },
+      "path": [
+        {
+          "description": "The index or data stream name",
+          "name": "index",
+          "required": true,
+          "type": {
+            "kind": "instance_of",
+            "type": {
+              "name": "Indices",
+              "namespace": "_types"
+            }
+          }
+        }
+      ],
+      "query": [],
+      "specLocation": "migrate/get_reindex_status/MigrateGetReindexStatusRequest.ts#L23-L37"
+    },
+    {
+      "kind": "response",
+      "body": {
+        "kind": "value",
+        "value": {
+          "kind": "instance_of",
+          "type": {
+            "name": "AcknowledgedResponseBase",
+            "namespace": "_types"
+          }
+        }
+      },
+      "name": {
+        "name": "Response",
+        "namespace": "migrate.get_reindex_status"
+      },
+      "specLocation": "migrate/get_reindex_status/MigrateGetReindexStatusResponse.ts#L22-L24"
+    },
+    {
+      "kind": "request",
+      "attachedBehaviors": [
+        "CommonQueryParameters"
+      ],
+      "body": {
+        "kind": "value",
+        "codegenName": "reindex",
+        "value": {
+          "kind": "instance_of",
+          "type": {
+            "name": "MigrateReindex",
+            "namespace": "migrate._types"
+          }
+        }
+      },
+      "description": "\"This API reindexes all legacy backing indices for a data stream. It does this in a persistent task. The persistent task id is returned immediately, and the reindexing work is completed in that task",
+      "inherits": {
+        "type": {
+          "name": "RequestBase",
+          "namespace": "_types"
+        }
+      },
+      "name": {
+        "name": "Request",
+        "namespace": "migrate.reindex"
+      },
+      "path": [],
+      "query": [],
+      "specLocation": "migrate/reindex/MigrateReindexRequest.ts#L23-L34"
+    },
+    {
+      "kind": "response",
+      "body": {
+        "kind": "value",
+        "value": {
+          "kind": "instance_of",
+          "type": {
+            "name": "AcknowledgedResponseBase",
+            "namespace": "_types"
+          }
+        }
+      },
+      "name": {
+        "name": "Response",
+        "namespace": "migrate.reindex"
+      },
+      "specLocation": "migrate/reindex/MigrateReindexResponse.ts#L22-L24"
+    },
     {
       "kind": "interface",
       "name": {
diff --git a/output/typescript/types.ts b/output/typescript/types.ts
index f8b9a2684d..8043ed27bf 100644
--- a/output/typescript/types.ts
+++ b/output/typescript/types.ts
@@ -13826,6 +13826,50 @@ export interface LogstashPutPipelineRequest extends RequestBase {
 
 export type LogstashPutPipelineResponse = boolean
 
+export interface MigrateCreateFrom {
+  mappings_override?: MappingTypeMapping
+  settings_override?: IndicesIndexSettings
+}
+
+export interface MigrateIndex {
+  index: Indices
+}
+
+export interface MigrateMigrateReindex {
+  mode: string
+  source: MigrateIndex
+}
+
+export interface MigrateCancelReindexRequest extends RequestBase {
+  index: Indices
+}
+
+export type MigrateCancelReindexResponse = AcknowledgedResponseBase
+
+export interface MigrateCreateFromRequest extends RequestBase {
+  source: string
+  dest: string
+  body?: MigrateCreateFrom
+}
+
+export interface MigrateCreateFromResponse {
+  acknowledged: boolean
+  index: IndexName
+  shards_acknowledged: boolean
+}
+
+export interface MigrateGetReindexStatusRequest extends RequestBase {
+  index: Indices
+}
+
+export type MigrateGetReindexStatusResponse = AcknowledgedResponseBase
+
+export interface MigrateReindexRequest extends RequestBase {
+  body?: MigrateMigrateReindex
+}
+
+export type MigrateReindexResponse = AcknowledgedResponseBase
+
 export interface MigrationDeprecationsDeprecation {
   details?: string
   level: MigrationDeprecationsDeprecationLevel
diff --git a/specification/_doc_ids/table.csv b/specification/_doc_ids/table.csv
index 7b06d87c01..88d9aa5f28 100644
--- a/specification/_doc_ids/table.csv
+++ b/specification/_doc_ids/table.csv
@@ -302,6 +302,7 @@ mapping-source-field,https://www.elastic.co/guide/en/elasticsearch/reference/{br
 mapping,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/mapping.html
 mapping,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/mapping.html
 mean-reciprocal,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/search-rank-eval.html#_mean_reciprocal_rank
+migrate,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migrate-data-stream.html
 migrate-index-allocation-filters,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migrate-index-allocation-filters.html
 migration-api-deprecation,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/migration-api-deprecation.html
 migration-api-feature-upgrade,https://www.elastic.co/guide/en/elasticsearch/reference/{branch}/feature-migration-api.html
diff --git a/specification/_json_spec/migrate.cancel_reindex.json b/specification/_json_spec/migrate.cancel_reindex.json
new file mode 100644
index 0000000000..6ab0ee44eb
--- /dev/null
+++ b/specification/_json_spec/migrate.cancel_reindex.json
@@ -0,0 +1,28 @@
+{
+  "migrate.cancel_reindex": {
+    "documentation": {
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/master/data-stream-reindex.html",
+      "description": "This API cancels migration reindex attempt for a data stream or index"
+    },
+    "stability": "experimental",
+    "visibility": "private",
+    "headers": {
+      "accept": ["application/json"],
+      "content_type": ["application/json"]
+    },
+    "url": {
+      "paths": [
+        {
+          "path": "/_migration/reindex/{index}/_cancel",
+          "methods": ["POST"],
+          "parts": {
+            "index": {
+              "type": "string",
+              "description": "The index or data stream name"
+            }
+          }
+        }
+      ]
+    }
+  }
+}
diff --git a/specification/_json_spec/migrate.create_from.json b/specification/_json_spec/migrate.create_from.json
new file mode 100644
index 0000000000..edb5037f66
--- /dev/null
+++ b/specification/_json_spec/migrate.create_from.json
@@ -0,0 +1,36 @@
+{
+  "migrate.create_from": {
+    "documentation": {
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/master/data-stream-reindex.html",
+      "description": "This API creates a destination from a source index. It copies the mappings and settings from the source index while allowing request settings and mappings to override the source values."
+    },
+    "stability": "experimental",
+    "visibility": "private",
+    "headers": {
+      "accept": ["application/json"],
+      "content_type": ["application/json"]
+    },
+    "url": {
+      "paths": [
+        {
+          "path": "/_create_from/{source}/{dest}",
+          "methods": ["PUT", "POST"],
+          "parts": {
+            "source": {
+              "type": "string",
+              "description": "The source index name"
+            },
+            "dest": {
+              "type": "string",
+              "description": "The destination index name"
+            }
+          }
+        }
+      ]
+    },
+    "body": {
+      "description": "The body contains the fields `mappings_override` and `settings_override`.",
+      "required": false
+    }
+  }
+}
diff --git a/specification/_json_spec/migrate.get_reindex_status.json b/specification/_json_spec/migrate.get_reindex_status.json
new file mode 100644
index 0000000000..d5361ff1bb
--- /dev/null
+++ b/specification/_json_spec/migrate.get_reindex_status.json
@@ -0,0 +1,28 @@
+{
+  "migrate.get_reindex_status": {
+    "documentation": {
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/master/data-stream-reindex.html",
+      "description": "This API returns the status of a migration reindex attempt for a data stream or index"
+    },
+    "stability": "experimental",
+    "visibility": "private",
+    "headers": {
+      "accept": ["application/json"],
+      "content_type": ["application/json"]
+    },
+    "url": {
+      "paths": [
+        {
+          "path": "/_migration/reindex/{index}/_status",
+          "methods": ["GET"],
+          "parts": {
+            "index": {
+              "type": "string",
+              "description": "The index or data stream name"
+            }
+          }
+        }
+      ]
+    }
+  }
+}
diff --git a/specification/_json_spec/migrate.reindex.json b/specification/_json_spec/migrate.reindex.json
new file mode 100644
index 0000000000..2736f7ecd7
--- /dev/null
+++ b/specification/_json_spec/migrate.reindex.json
@@ -0,0 +1,26 @@
+{
+  "migrate.reindex": {
+    "documentation": {
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/master/data-stream-reindex.html",
+      "description": "This API reindexes all legacy backing indices for a data stream. It does this in a persistent task. The persistent task id is returned immediately, and the reindexing work is completed in that task"
+    },
+    "stability": "experimental",
+    "visibility": "private",
+    "headers": {
+      "accept": ["application/json"],
+      "content_type": ["application/json"]
+    },
+    "url": {
+      "paths": [
+        {
+          "path": "/_migration/reindex",
+          "methods": ["POST"]
+        }
+      ]
+    },
+    "body": {
+      "description": "The body contains the fields `mode` and `source.index`, where the only mode currently supported is `upgrade`, and the `source.index` must be a data stream name",
+      "required": true
+    }
+  }
+}
diff --git a/specification/migrate/_types/CreateFrom.ts b/specification/migrate/_types/CreateFrom.ts
new file mode 100644
index 0000000000..00f1e3c920
--- /dev/null
+++ b/specification/migrate/_types/CreateFrom.ts
@@ -0,0 +1,32 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { IndexSettings } from '@indices/_types/IndexSettings'
+import { TypeMapping } from '@_types/mapping/TypeMapping'
+
+export class CreateFrom {
+  /**
+   * Mappings overrides to be applied to the destination index (optional)
+   */
+  mappings_override?: TypeMapping
+  /**
+   * Settings overrides to be applied to the destination index (optional)
+   */
+  settings_override?: IndexSettings
+}
diff --git a/specification/migrate/_types/MigrateReindex.ts b/specification/migrate/_types/MigrateReindex.ts
new file mode 100644
index 0000000000..15863d9b02
--- /dev/null
+++ b/specification/migrate/_types/MigrateReindex.ts
@@ -0,0 +1,35 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { Indices } from '@_types/common'
+
+export class MigrateReindex {
+  /**
+   * Reindex mode. Currently only 'upgrade' is supported.
+   */
+  mode: string
+  /**
+   * The source index or data stream (only data streams are currently supported).
+   */
+  source: Index
+}
+
+export class Index {
+  index: Indices
+}
diff --git a/specification/migrate/cancel_reindex/MigrateCancelReindexRequest.ts b/specification/migrate/cancel_reindex/MigrateCancelReindexRequest.ts
new file mode 100644
index 0000000000..2d75a195fa
--- /dev/null
+++ b/specification/migrate/cancel_reindex/MigrateCancelReindexRequest.ts
@@ -0,0 +1,37 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { RequestBase } from '@_types/Base'
+import { Indices } from '@_types/common'
+
+/**
+ * This API cancels a migration reindex attempt for a data stream or index
+ *
+ * @rest_spec_name migrate.cancel_reindex
+ * @availability stack since=8.18.0 stability=experimental
+ * @availability serverless stability=experimental visibility=private
+ * @doc_id migrate
+ * @doc_tag cancel_reindex
+ */
+export interface Request extends RequestBase {
+  path_parts: {
+    /** The index or data stream name */
+    index: Indices
+  }
+}
diff --git a/specification/migrate/cancel_reindex/MigrateCancelReindexResponse.ts b/specification/migrate/cancel_reindex/MigrateCancelReindexResponse.ts
new file mode 100644
index 0000000000..7374da4a4c
--- /dev/null
+++ b/specification/migrate/cancel_reindex/MigrateCancelReindexResponse.ts
@@ -0,0 +1,24 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { AcknowledgedResponseBase } from '@_types/Base'
+
+export class Response {
+  body: AcknowledgedResponseBase
+}
diff --git a/specification/migrate/create_from/MigrateCreateFromRequest.ts b/specification/migrate/create_from/MigrateCreateFromRequest.ts
new file mode 100644
index 0000000000..691f086a31
--- /dev/null
+++ b/specification/migrate/create_from/MigrateCreateFromRequest.ts
@@ -0,0 +1,41 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { RequestBase } from '@_types/Base'
+import { CreateFrom } from '../_types/CreateFrom'
+
+/**
+ * This API creates a destination from a source index. It copies the mappings and settings from the source index while allowing request settings and mappings to override the source values.
+ *
+ * @rest_spec_name migrate.create_from
+ * @availability stack since=8.18.0 stability=experimental
+ * @availability serverless stability=experimental visibility=private
+ * @doc_id migrate
+ * @doc_tag create_from
+ */
+export interface Request extends RequestBase {
+  path_parts: {
+    /** The source index or data stream name */
+    source: string
+    /** The destination index or data stream name */
+    dest: string
+  }
+  /** @codegen_name create_from */
+  body: CreateFrom
+}
diff --git a/specification/migrate/create_from/MigrateCreateFromResponse.ts b/specification/migrate/create_from/MigrateCreateFromResponse.ts
new file mode 100644
index 0000000000..209a7ccdb4
--- /dev/null
+++ b/specification/migrate/create_from/MigrateCreateFromResponse.ts
@@ -0,0 +1,28 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { IndexName } from '@_types/common'
+
+export class Response {
+  body: {
+    acknowledged: boolean
+    index: IndexName
+    shards_acknowledged: boolean
+  }
+}
diff --git a/specification/migrate/get_reindex_status/MigrateGetReindexStatusRequest.ts b/specification/migrate/get_reindex_status/MigrateGetReindexStatusRequest.ts
new file mode 100644
index 0000000000..c490e71a36
--- /dev/null
+++ b/specification/migrate/get_reindex_status/MigrateGetReindexStatusRequest.ts
@@ -0,0 +1,37 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { RequestBase } from '@_types/Base'
+import { Indices } from '@_types/common'
+
+/**
+ * This API returns the status of a migration reindex attempt for a data stream or index
+ *
+ * @rest_spec_name migrate.get_reindex_status
+ * @availability stack since=8.18.0 stability=experimental
+ * @availability serverless stability=experimental visibility=private
+ * @doc_id migrate
+ * @doc_tag get_reindex_status
+ */
+export interface Request extends RequestBase {
+  path_parts: {
+    /** The index or data stream name */
+    index: Indices
+  }
+}
diff --git a/specification/migrate/get_reindex_status/MigrateGetReindexStatusResponse.ts b/specification/migrate/get_reindex_status/MigrateGetReindexStatusResponse.ts
new file mode 100644
index 0000000000..7374da4a4c
--- /dev/null
+++ b/specification/migrate/get_reindex_status/MigrateGetReindexStatusResponse.ts
@@ -0,0 +1,24 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { AcknowledgedResponseBase } from '@_types/Base'
+
+export class Response {
+  body: AcknowledgedResponseBase
+}
diff --git a/specification/migrate/reindex/MigrateReindexRequest.ts b/specification/migrate/reindex/MigrateReindexRequest.ts
new file mode 100644
index 0000000000..425e88c60d
--- /dev/null
+++ b/specification/migrate/reindex/MigrateReindexRequest.ts
@@ -0,0 +1,34 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { RequestBase } from '@_types/Base'
+import { MigrateReindex } from '../_types/MigrateReindex'
+
+/**
+ * "This API reindexes all legacy backing indices for a data stream. It does this in a persistent task. The persistent task id is returned immediately, and the reindexing work is completed in that task
+ *
+ * @rest_spec_name migrate.reindex
+ * @availability stack since=8.18.0 stability=experimental
+ * @doc_id migrate
+ * @doc_tag reindex
+ */
+export interface Request extends RequestBase {
+  /** @codegen_name reindex */
+  body: MigrateReindex
+}
diff --git a/specification/migrate/reindex/MigrateReindexResponse.ts b/specification/migrate/reindex/MigrateReindexResponse.ts
new file mode 100644
index 0000000000..7374da4a4c
--- /dev/null
+++ b/specification/migrate/reindex/MigrateReindexResponse.ts
@@ -0,0 +1,24 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { AcknowledgedResponseBase } from '@_types/Base'
+
+export class Response {
+  body: AcknowledgedResponseBase
+}