diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2019-08-01-preview/authorization-UsageMetricsCalls.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2019-08-01-preview/authorization-UsageMetricsCalls.json
new file mode 100644
index 000000000000..a723ef63e1a8
--- /dev/null
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2019-08-01-preview/authorization-UsageMetricsCalls.json
@@ -0,0 +1,105 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "AuthorizationManagementClient",
+    "version": "2019-08-01-preview",
+    "description": "Role based access control provides you a way to apply granular level policy administration down to individual resources or resource groups. These operations enable you to manage role assignments. A role assignment grants access to Azure Active Directory users."
+  },
+  "host": "management.azure.com",
+  "schemes": [
+    "https"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "produces": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "flow": "implicit",
+      "description": "Azure Active Directory OAuth2 Flow",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "paths": {
+    "/subscriptions/{subscriptionId}/providers/Microsoft.Authorization/roleAssignmentsUsageMetrics": {
+      "get": {
+        "tags": [
+          "RoleAssignmentMetrics"
+        ],
+        "operationId": "RoleAssignmentMetrics_GetMetricsForSubscription",
+        "description": "Get role assignment usage metrics for a subscription",
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Returns current role assignment usage metrics.",
+            "schema": {
+              "$ref": "#/definitions/RoleAssignmentMetricsResult"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-examples": {
+          "Get role assignment metrics for subscription": {
+            "$ref": "./examples/RoleAssignmentMetrics_GetForSubscription.json"
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "RoleAssignmentMetricsResult": {
+      "properties": {
+        "subscriptionId": {
+          "type": "string",
+          "readOnly": true,
+          "description": "The subscription ID."
+        },
+        "roleAssignmentsLimit": {
+          "type": "integer",
+          "format": "int64",
+          "readOnly": true,
+          "description": "The role assignment limit."
+        },
+        "roleAssignmentsCurrentCount": {
+          "type": "integer",
+          "format": "int64",
+          "readOnly": true,
+          "description": "The number of current role assignments."
+        },
+        "roleAssignmentsRemainingCount": {
+          "type": "integer",
+          "format": "int64",
+          "readOnly": true,
+          "description": "The number of remaining role assignments available."
+        }
+      },
+      "description": "Role Assignment Metrics"
+    }
+  },
+  "parameters": {}
+}
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2019-08-01-preview/examples/RoleAssignmentMetrics_GetForSubscription.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2019-08-01-preview/examples/RoleAssignmentMetrics_GetForSubscription.json
new file mode 100644
index 000000000000..0a361d0fd93c
--- /dev/null
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2019-08-01-preview/examples/RoleAssignmentMetrics_GetForSubscription.json
@@ -0,0 +1,16 @@
+{
+  "parameters": {
+    "subscriptionId": "a925f2f7-5c63-4b7b-8799-25a5f97bc3b2",
+    "api-version": "2019-08-01-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "subscriptionId": "a925f2f7-5c63-4b7b-8799-25a5f97bc3b2",
+        "roleAssignmentsLimit": 2000,
+        "roleAssignmentsCurrentCount": 1530,
+        "roleAssignmentsRemainingCount": 470
+      }
+    }
+  }
+}
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/authorization-RoleAssignmentsCalls.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/authorization-RoleAssignmentsCalls.json
index 401a3f049b12..420d2b3a84b8 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/authorization-RoleAssignmentsCalls.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/authorization-RoleAssignmentsCalls.json
@@ -249,6 +249,13 @@
               "$ref": "#/definitions/RoleAssignment"
             }
           },
+          "500": {
+            "x-ms-error-response": true,
+            "description": "Error.",
+            "schema": {
+              "$ref": "#/definitions/CustomErrorResponse"
+            }
+          },
           "default": {
             "description": "Error response describing why the operation failed.",
             "schema": {
@@ -417,6 +424,13 @@
               "$ref": "#/definitions/RoleAssignment"
             }
           },
+          "500": {
+            "x-ms-error-response": true,
+            "description": "Error.",
+            "schema": {
+              "$ref": "#/definitions/CustomErrorResponse"
+            }
+          },
           "default": {
             "description": "Error response describing why the operation failed.",
             "schema": {
@@ -470,6 +484,15 @@
     }
   },
   "definitions": {
+    "CustomErrorResponse": {
+      "properties": {
+        "message": {
+          "type": "string",
+          "description": "Description of the error."
+        }
+      },
+      "description": "Descriptive error response."
+    },
     "RoleAssignmentFilter": {
       "properties": {
         "principalId": {
@@ -529,6 +552,7 @@
             "DirectoryObjectOrGroup",
             "Everyone"
           ],
+          "default": "User",
           "x-ms-enum": {
             "name": "PrincipalType",
             "modelAsString": true
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateById.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateById.json
index 388fefd9f5c8..3cbfd03cece5 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateById.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateById.json
@@ -39,6 +39,11 @@
         "type": "Microsoft.Authorization/roleAssignments",
         "name": "b0f43c54-e787-4862-89b1-a653fa9cf747"
       }
+    },
+    "500": {
+      "body": {
+        "message": "Something went wrong."
+      }
     }
   }
 }
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResource.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResource.json
index 1aa8c936067e..79b5aa0fecdf 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResource.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResource.json
@@ -40,6 +40,11 @@
         "type": "Microsoft.Authorization/roleAssignments",
         "name": "05c5a614-a7d6-4502-b150-c2fb455033ff"
       }
+    },
+    "500": {
+      "body": {
+        "message": "Something went wrong."
+      }
     }
   }
 }
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResourceGroup.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResourceGroup.json
index 8a757673f971..d69cac6feacb 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResourceGroup.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForResourceGroup.json
@@ -40,6 +40,11 @@
         "type": "Microsoft.Authorization/roleAssignments",
         "name": "05c5a614-a7d6-4502-b150-c2fb455033ff"
       }
+    },
+    "500": {
+      "body": {
+        "message": "Something went wrong."
+      }
     }
   }
 }
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForSubscription.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForSubscription.json
index bdddecfd6d1e..3ac8fed1d21a 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForSubscription.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-03-01-preview/examples/RoleAssignments_CreateForSubscription.json
@@ -40,6 +40,11 @@
         "type": "Microsoft.Authorization/roleAssignments",
         "name": "05c5a614-a7d6-4502-b150-c2fb455033ff"
       }
+    },
+    "500": {
+      "body": {
+        "message": "Something went wrong."
+      }
     }
   }
 }
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/authorization-RoleAssignmentsCalls.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/authorization-RoleAssignmentsCalls.json
index 687494cb08ce..07214ae149cf 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/authorization-RoleAssignmentsCalls.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/authorization-RoleAssignmentsCalls.json
@@ -252,6 +252,13 @@
               "$ref": "#/definitions/RoleAssignment"
             }
           },
+          "500": {
+            "x-ms-error-response": true,
+            "description": "Error.",
+            "schema": {
+              "$ref": "#/definitions/CustomErrorResponse"
+            }
+          },
           "default": {
             "description": "Error response describing why the operation failed.",
             "schema": {
@@ -390,6 +397,13 @@
               "$ref": "#/definitions/RoleAssignment"
             }
           },
+          "500": {
+            "x-ms-error-response": true,
+            "description": "Error.",
+            "schema": {
+              "$ref": "#/definitions/CustomErrorResponse"
+            }
+          },
           "default": {
             "description": "Error response describing why the operation failed.",
             "schema": {
@@ -544,6 +558,15 @@
     }
   },
   "definitions": {
+    "CustomErrorResponse": {
+      "properties": {
+        "message": {
+          "type": "string",
+          "description": "Description of the error."
+        }
+      },
+      "description": "Descriptive error response."
+    },
     "RoleAssignmentFilter": {
       "properties": {
         "principalId": {
@@ -698,6 +721,7 @@
             "DirectoryObjectOrGroup",
             "Everyone"
           ],
+          "default": "User",
           "x-ms-enum": {
             "name": "PrincipalType",
             "modelAsString": true
@@ -718,6 +742,10 @@
         "conditionVersion": {
           "type": "string",
           "description": "Version of the condition. Currently accepted value is '2.0'"
+        },
+        "delegatedManagedIdentityResourceId": {
+          "type": "string",
+          "description": "Id of the delegated managed identity resource"
         }
       },
       "required": [
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignment.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignment.json
index c87cfe4307e7..cd628b536a42 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignment.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignment.json
@@ -32,6 +32,11 @@
         "type": "Microsoft.Authorization/roleAssignments",
         "name": "roleassignmentId"
       }
+    },
+    "500": {
+      "body": {
+        "message": "Something went wrong."
+      }
     }
   }
 }
diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignmentById.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignmentById.json
index 965fb76e36b5..7e84f0089ef7 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignmentById.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2020-04-01-preview/examples/PutRoleAssignmentById.json
@@ -32,6 +32,11 @@
         "type": "Microsoft.Authorization/roleAssignments",
         "name": "roleassignmentId"
       }
+    },
+    "500": {
+      "body": {
+        "message": "Something went wrong."
+      }
     }
   }
 }
diff --git a/specification/authorization/resource-manager/readme.md b/specification/authorization/resource-manager/readme.md
index 86b6a3deb041..ac514ba6e3e3 100644
--- a/specification/authorization/resource-manager/readme.md
+++ b/specification/authorization/resource-manager/readme.md
@@ -101,6 +101,7 @@ input-file:
 - Microsoft.Authorization/preview/2018-01-01-preview/authorization-RoleDefinitionsCalls.json
 - Microsoft.Authorization/preview/2018-07-01-preview/authorization-DenyAssignmentGetCalls.json
 - Microsoft.Authorization/preview/2020-04-01-preview/authorization-RoleAssignmentsCalls.json
+- Microsoft.Authorization/preview/2019-08-01-preview/authorization-UsageMetricsCalls.json
 ```
 
 ### Tag: package-2020-04-01-preview-only
@@ -125,6 +126,7 @@ input-file:
 - Microsoft.Authorization/preview/2020-03-01-preview/authorization-DenyAssignmentGetCalls.json
 - Microsoft.Authorization/preview/2020-03-01-preview/authorization-RoleAssignmentsCalls.json
 - Microsoft.Authorization/preview/2020-03-01-preview/authorization-PermissionsCalls.json
+- Microsoft.Authorization/preview/2019-08-01-preview/authorization-UsageMetricsCalls.json
 ```
 
 ### Tag: package-2018-09-01-preview