diff --git a/scripts/update-endpoints/templates/endpoints.ts.template b/scripts/update-endpoints/templates/endpoints.ts.template
index 02679a1f2..3fa7bb06e 100644
--- a/scripts/update-endpoints/templates/endpoints.ts.template
+++ b/scripts/update-endpoints/templates/endpoints.ts.template
@@ -4,6 +4,12 @@ import type { OctokitResponse } from "../OctokitResponse";
 import type { RequestHeaders } from "../RequestHeaders";
 import type { RequestRequestOptions } from "../RequestRequestOptions";
 
+/**
+ * @license (MIT OR CC0-1.0)
+ * @source https://github.com/sindresorhus/type-fest/blob/570e27f8fdaee37ef5d5e0fbf241e0212ff8fc1a/source/simplify.d.ts
+ */
+export type Simplify<T> = {[KeyType in keyof T]: T[KeyType]} & {};
+
 // https://stackoverflow.com/a/50375286/206879
 type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends (
   k: infer I
@@ -40,30 +46,34 @@ type ExtractRequestBody<T> = "requestBody" extends keyof T
 type ToOctokitParameters<T> = ExtractParameters<T> & ExtractRequestBody<Required<T>>;
 
 type Operation<Url extends keyof paths, Method extends keyof paths[Url]> = {
-  parameters: ToOctokitParameters<paths[Url][Method]>;
-  request: {
-    method: Method extends keyof MethodsMap ? MethodsMap[Method] : never;
-    url: Url;
-    headers: RequestHeaders;
-    request: RequestRequestOptions;
-  };
+  parameters: Simplify<ToOctokitParameters<paths[Url][Method]>>;
+  request: Method extends ReadOnlyMethods
+    ? {
+        method: Method extends string ? Uppercase<Method> : never;
+        url: Url;
+        headers: RequestHeaders;
+        request: RequestRequestOptions;
+      }
+    : {
+        method: Method extends string ? Uppercase<Method> : never;
+        url: Url;
+        headers: RequestHeaders;
+        request: RequestRequestOptions;
+        data: ExtractRequestBody<paths[Url][Method]>;
+      };
   response: ExtractOctokitResponse<paths[Url][Method]>;
 };
 
-type MethodsMap = {
-  delete: "DELETE";
-  get: "GET";
-  patch: "PATCH";
-  post: "POST";
-  put: "PUT";
-};
-type SuccessStatuses = 200 | 201 | 202 | 204;
+type ReadOnlyMethods = "get" | "head";
+type SuccessStatuses = 200 | 201 | 202 | 204 | 205;
 type RedirectStatuses = 301 | 302;
-type EmptyResponseStatuses = 201 | 204;
+type EmptyResponseStatuses = 201 | 204 | 205;
 type KnownJsonResponseTypes =
   | "application/json"
+  | "application/octocat-stream" // GET /octocat
   | "application/scim+json"
-  | "text/html";
+  | "text/html"
+  | "text/plain"; // GET /zen
 
 type SuccessResponseDataType<Responses> = {
   [K in SuccessStatuses & keyof Responses]: GetContentKeyIfPresent<
diff --git a/src/generated/Endpoints.ts b/src/generated/Endpoints.ts
index 3ebe565b4..b32eaf5e8 100644
--- a/src/generated/Endpoints.ts
+++ b/src/generated/Endpoints.ts
@@ -4,6 +4,12 @@ import type { OctokitResponse } from "../OctokitResponse";
 import type { RequestHeaders } from "../RequestHeaders";
 import type { RequestRequestOptions } from "../RequestRequestOptions";
 
+/**
+ * @license (MIT OR CC0-1.0)
+ * @source https://github.com/sindresorhus/type-fest/blob/570e27f8fdaee37ef5d5e0fbf241e0212ff8fc1a/source/simplify.d.ts
+ */
+export type Simplify<T> = { [KeyType in keyof T]: T[KeyType] } & {};
+
 // https://stackoverflow.com/a/50375286/206879
 type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends (
   k: infer I,
@@ -41,30 +47,34 @@ type ToOctokitParameters<T> = ExtractParameters<T> &
   ExtractRequestBody<Required<T>>;
 
 type Operation<Url extends keyof paths, Method extends keyof paths[Url]> = {
-  parameters: ToOctokitParameters<paths[Url][Method]>;
-  request: {
-    method: Method extends keyof MethodsMap ? MethodsMap[Method] : never;
-    url: Url;
-    headers: RequestHeaders;
-    request: RequestRequestOptions;
-  };
+  parameters: Simplify<ToOctokitParameters<paths[Url][Method]>>;
+  request: Method extends ReadOnlyMethods
+    ? {
+        method: Method extends string ? Uppercase<Method> : never;
+        url: Url;
+        headers: RequestHeaders;
+        request: RequestRequestOptions;
+      }
+    : {
+        method: Method extends string ? Uppercase<Method> : never;
+        url: Url;
+        headers: RequestHeaders;
+        request: RequestRequestOptions;
+        data: ExtractRequestBody<paths[Url][Method]>;
+      };
   response: ExtractOctokitResponse<paths[Url][Method]>;
 };
 
-type MethodsMap = {
-  delete: "DELETE";
-  get: "GET";
-  patch: "PATCH";
-  post: "POST";
-  put: "PUT";
-};
-type SuccessStatuses = 200 | 201 | 202 | 204;
+type ReadOnlyMethods = "get" | "head";
+type SuccessStatuses = 200 | 201 | 202 | 204 | 205;
 type RedirectStatuses = 301 | 302;
-type EmptyResponseStatuses = 201 | 204;
+type EmptyResponseStatuses = 201 | 204 | 205;
 type KnownJsonResponseTypes =
   | "application/json"
+  | "application/octocat-stream" // GET /octocat
   | "application/scim+json"
-  | "text/html";
+  | "text/html"
+  | "text/plain"; // GET /zen
 
 type SuccessResponseDataType<Responses> = {
   [K in SuccessStatuses & keyof Responses]: GetContentKeyIfPresent<