diff --git a/rest-api-spec/src/main/resources/rest-api-spec/api/inference.put_ai21.json b/rest-api-spec/src/main/resources/rest-api-spec/api/inference.put_ai21.json
new file mode 100644
index 0000000000000..6d59087402068
--- /dev/null
+++ b/rest-api-spec/src/main/resources/rest-api-spec/api/inference.put_ai21.json
@@ -0,0 +1,35 @@
+{
+  "inference.put_ai21": {
+    "documentation": {
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/current/infer-service-ai21.html",
+      "description": "Configure a AI21 inference endpoint"
+    },
+    "stability": "stable",
+    "visibility": "public",
+    "headers": {
+      "accept": ["application/json"],
+      "content_type": ["application/json"]
+    },
+    "url": {
+      "paths": [
+        {
+          "path": "/_inference/{task_type}/{ai21_inference_id}",
+          "methods": ["PUT"],
+          "parts": {
+            "task_type": {
+              "type": "string",
+              "description": "The task type"
+            },
+            "ai21_inference_id": {
+              "type": "string",
+              "description": "The inference ID"
+            }
+          }
+        }
+      ]
+    },
+    "body": {
+      "description": "The inference endpoint's task and service settings"
+    }
+  }
+}
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/api/inference.put_llama.json b/rest-api-spec/src/main/resources/rest-api-spec/api/inference.put_llama.json
new file mode 100644
index 0000000000000..5551f655cb616
--- /dev/null
+++ b/rest-api-spec/src/main/resources/rest-api-spec/api/inference.put_llama.json
@@ -0,0 +1,35 @@
+{
+  "inference.put_llama": {
+    "documentation": {
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/current/infer-service-llama.html",
+      "description": "Configure a Llama inference endpoint"
+    },
+    "stability": "stable",
+    "visibility": "public",
+    "headers": {
+      "accept": ["application/json"],
+      "content_type": ["application/json"]
+    },
+    "url": {
+      "paths": [
+        {
+          "path": "/_inference/{task_type}/{llama_inference_id}",
+          "methods": ["PUT"],
+          "parts": {
+            "task_type": {
+              "type": "string",
+              "description": "The task type"
+            },
+            "llama_inference_id": {
+              "type": "string",
+              "description": "The inference ID"
+            }
+          }
+        }
+      ]
+    },
+    "body": {
+      "description": "The inference endpoint's task and service settings"
+    }
+  }
+}
diff --git a/rest-api-spec/src/main/resources/schema.json b/rest-api-spec/src/main/resources/schema.json
index 02fdd920f9216..24b75aabefa89 100644
--- a/rest-api-spec/src/main/resources/schema.json
+++ b/rest-api-spec/src/main/resources/schema.json
@@ -6,12 +6,12 @@
         "Api": {
             "type": "object",
             "propertyNames": {
-                "pattern": "^(?:[a-z]+?(_[a-z]+)*(\\.[a-z]+?(_[a-z]+)*)?|_internal\\.[a-z]+?(_[a-z]+)*)$"
+                "pattern": "^(?:[a-z][a-z0-9]*?(_[a-z0-9]+)*(\\.[a-z][a-z0-9]*?(_[a-z0-9]+)*)?|_internal\\.[a-z][a-z0-9]*?(_[a-z0-9]+)*)$"
             },
             "minProperties": 1,
             "maxProperties": 1,
             "patternProperties": {
-                "^(?:[a-z]+?(_[a-z]+)*(\\.[a-z]+?(_[a-z]+)*)?|_internal\\.[a-z]+?(_[a-z]+)*)$": {
+                "^(?:[a-z][a-z0-9]*?(_[a-z0-9]+)*(\\.[a-z][a-z0-9]*?(_[a-z0-9]+)*)?|_internal\\.[a-z][a-z0-9]*?(_[a-z0-9]+)*)$": {
                     "$ref": "#/definitions/Components"
                 }
             },
@@ -135,10 +135,10 @@
             "type": "object",
             "additionalProperties": true,
             "propertyNames": {
-              "pattern": "^_?[a-z]+?(_[a-z]+)*$"
+              "pattern": "^_?[a-z][a-z0-9]*?(_[a-z0-9]+)*$"
             },
             "patternProperties": {
-                "^_?[a-z]+?(_[a-z]+)*$": {
+                "^_?[a-z][a-z0-9]*?(_[a-z0-9]+)*$": {
                     "$ref": "#/definitions/ParamPart"
                 }
             },
@@ -232,10 +232,10 @@
             "type": "object",
             "additionalProperties": true,
             "propertyNames": {
-              "pattern": "^_?[a-z]+?(_[a-z]+)*$"
+              "pattern": "^_?[a-z][a-z0-9]*?(_[a-z0-9]+)*$"
             },
             "patternProperties": {
-                "^_?[a-z]+?(_[a-z]+)*$": {
+                "^_?[a-z][a-z0-9]*?(_[a-z0-9]+)*$": {
                     "$ref": "#/definitions/ParamPart"
                 }
             },