feat(mcp): enable Payload MCP plugin

Register mcpPlugin on the Payload config. Auth now also accepts
payload-mcp-api-keys, so the generated types carry the new
collection and the user union widens accordingly. Follow-up commits
guard user auth paths against these API-key sessions.

Also apply incidental prettier formatting to generatePlainText().

package.json

@@ -35,6 +35,7 @@
     "@payloadcms/email-nodemailer": "3.88.0",
     "@payloadcms/next": "3.88.0",
     "@payloadcms/payload-cloud": "3.88.0",
+    "@payloadcms/plugin-mcp": "^3.88.0",
     "@payloadcms/richtext-lexical": "3.88.0",
     "@payloadcms/ui": "3.88.0",
     "@radix-ui/react-avatar": "^1.2.6",

src/payload-types.ts

@@ -64,6 +64,7 @@ export type SupportedTimezones =
 export interface Config {
   auth: {
     users: UserAuthOperations;
+    'payload-mcp-api-keys': PayloadMcpApiKeyAuthOperations;
   };
   blocks: {};
   collections: {
@@ -112,6 +113,7 @@ export interface Config {
     'arma-sync-events': ArmaSyncEvent;
     'arma-commands': ArmaCommand;
     'plugin-ai-instructions': PluginAiInstruction;
+    'payload-mcp-api-keys': PayloadMcpApiKey;
     'payload-kv': PayloadKv;
     'payload-locked-documents': PayloadLockedDocument;
     'payload-preferences': PayloadPreference;
@@ -171,6 +173,7 @@ export interface Config {
     'arma-sync-events': ArmaSyncEventsSelect<false> | ArmaSyncEventsSelect<true>;
     'arma-commands': ArmaCommandsSelect<false> | ArmaCommandsSelect<true>;
     'plugin-ai-instructions': PluginAiInstructionsSelect<false> | PluginAiInstructionsSelect<true>;
+    'payload-mcp-api-keys': PayloadMcpApiKeysSelect<false> | PayloadMcpApiKeysSelect<true>;
     'payload-kv': PayloadKvSelect<false> | PayloadKvSelect<true>;
     'payload-locked-documents': PayloadLockedDocumentsSelect<false> | PayloadLockedDocumentsSelect<true>;
     'payload-preferences': PayloadPreferencesSelect<false> | PayloadPreferencesSelect<true>;
@@ -192,7 +195,7 @@ export interface Config {
   widgets: {
     collections: CollectionsWidget;
   };
-  user: User;
+  user: User | PayloadMcpApiKey;
   jobs: {
     tasks: unknown;
     workflows: unknown;
@@ -214,6 +217,24 @@ export interface UserAuthOperations {
     username: string;
   };
 }
+export interface PayloadMcpApiKeyAuthOperations {
+  forgotPassword: {
+    email: string;
+    password: string;
+  };
+  login: {
+    email: string;
+    password: string;
+  };
+  registerFirstUser: {
+    email: string;
+    password: string;
+  };
+  unlock: {
+    email: string;
+    password: string;
+  };
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "media".
@@ -2872,6 +2893,33 @@ export interface PluginAiInstruction {
   updatedAt: string;
   createdAt: string;
 }
+/**
+ * API keys control which collections, resources, tools, and prompts MCP clients can access
+ *
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "payload-mcp-api-keys".
+ */
+export interface PayloadMcpApiKey {
+  id: number;
+  /**
+   * The user that the API key is associated with.
+   */
+  user: number | User;
+  /**
+   * A useful label for the API key.
+   */
+  label?: string | null;
+  /**
+   * The purpose of the API key.
+   */
+  description?: string | null;
+  updatedAt: string;
+  createdAt: string;
+  enableAPIKey?: boolean | null;
+  apiKey?: string | null;
+  apiKeyIndex?: string | null;
+  collection: 'payload-mcp-api-keys';
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "payload-kv".
@@ -3075,11 +3123,20 @@ export interface PayloadLockedDocument {
     | ({
         relationTo: 'plugin-ai-instructions';
         value: number | PluginAiInstruction;
+      } | null)
+    | ({
+        relationTo: 'payload-mcp-api-keys';
+        value: number | PayloadMcpApiKey;
       } | null);
   globalSlug?: string | null;
-  user: {
+  user:
+    | {
         relationTo: 'users';
         value: number | User;
+      }
+    | {
+        relationTo: 'payload-mcp-api-keys';
+        value: number | PayloadMcpApiKey;
       };
   updatedAt: string;
   createdAt: string;
@@ -3090,9 +3147,14 @@ export interface PayloadLockedDocument {
  */
 export interface PayloadPreference {
   id: number;
-  user: {
+  user:
+    | {
         relationTo: 'users';
         value: number | User;
+      }
+    | {
+        relationTo: 'payload-mcp-api-keys';
+        value: number | PayloadMcpApiKey;
       };
   key?: string | null;
   value?:
@@ -4364,6 +4426,20 @@ export interface PluginAiInstructionsSelect<T extends boolean = true> {
   updatedAt?: T;
   createdAt?: T;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "payload-mcp-api-keys_select".
+ */
+export interface PayloadMcpApiKeysSelect<T extends boolean = true> {
+  user?: T;
+  label?: T;
+  description?: T;
+  updatedAt?: T;
+  createdAt?: T;
+  enableAPIKey?: T;
+  apiKey?: T;
+  apiKeyIndex?: T;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "payload-kv_select".

src/payload.config.ts

@@ -56,6 +56,7 @@ import { nodemailerAdapter } from "@payloadcms/email-nodemailer";
 import nodemailer from "nodemailer";
 import { Shims } from "@/collections/Shims";
 import { payloadAiPlugin, PayloadAiPluginLexicalEditorFeature } from "@ai-stack/payloadcms";
+import { mcpPlugin } from "@payloadcms/plugin-mcp";
 import { createOpenAI } from "@ai-sdk/openai";
 import { createTextStreamResponse, jsonSchema, streamObject } from "ai";
 
@@ -104,11 +105,7 @@ function plainTextToLexicalJson(text: string): Record<string, unknown> {
   };
 }
 
-async function generatePlainText(
-  prompt: string,
-  system: string,
-  model: string,
-): Promise<string> {
+async function generatePlainText(prompt: string, system: string, model: string): Promise<string> {
   const baseUrl = process.env.UNSLOTH_URL || "https://uns.onyxsimple.com/v1";
   const response = await fetch(`${baseUrl}/chat/completions`, {
     method: "POST",
@@ -288,6 +285,7 @@ export default buildConfig({
   plugins: [
     // payloadCloudPlugin(),
     // storage-adapter-placeholder
+    mcpPlugin({}),
     payloadAiPlugin({
       collections: {
         [GameHardResources.slug]: true,