refactor(junior): register core features outside plugins

packages/junior/src/app.ts

@@ -693,7 +693,7 @@ export async function createApp(options?: JuniorAppOptions): Promise<Hono> {
     validateBuildIncludesPluginPackages(pluginConfig, virtualConfig);
   }
   validateBuildIncludesPluginRuntimeRegistrations(plugins, virtualConfig);
-  validatePlugins(plugins);
+  validatePlugins(configuredPlugins?.registrations ?? []);
   getDb();
   const shouldValidatePluginCatalog =
     hasConfiguredPluginCatalog(pluginConfig) ||

packages/junior/src/chat/briefs/registration.ts

@@ -1,6 +1,3 @@
-import type { PluginRegistration } from "@sentry/junior-plugin-api";
-import { briefsTaskRegistration } from "./task";
-
 type BriefsConfig = Readonly<{ enabled?: boolean }>;
 
 let configuredBriefs: BriefsConfig = {};
@@ -16,8 +13,3 @@ export function setBriefsConfig(config?: { enabled?: boolean }): BriefsConfig {
 export function isBriefsEnabled(): boolean {
   return configuredBriefs.enabled === true;
 }
-
-/** Return enabled core task registrations. */
-export function coreTaskRegistrations(): PluginRegistration[] {
-  return isBriefsEnabled() ? [briefsTaskRegistration] : [];
-}

packages/junior/src/chat/briefs/task.ts

@@ -189,8 +189,8 @@ export async function updateConversationBrief(
   );
 }
 
-/** Core task registration kept outside the installed plugin catalog. */
-export const briefsTaskRegistration: PluginRegistration = {
+/** Register Briefs outside the installed plugin catalog. */
+export const briefsFeatureRegistration: PluginRegistration = {
   manifest: {
     name: "briefs",
     displayName: "Briefs",

packages/junior/src/chat/core-features/README.md

@@ -0,0 +1,5 @@
+# Core features
+
+Core features use the plugin runtime contract. They do not use plugin discovery or appear in the installed plugin catalog.
+
+`registration.ts` owns core feature registration and reserved names.

packages/junior/src/chat/core-features/registration.ts

@@ -0,0 +1,40 @@
+import type { PluginRegistration } from "@sentry/junior-plugin-api";
+import { isBriefsEnabled } from "@/chat/briefs/registration";
+import { briefsFeatureRegistration } from "@/chat/briefs/task";
+
+const coreFeatures = [
+  { isEnabled: isBriefsEnabled, registration: briefsFeatureRegistration },
+];
+/** Return all core registrations, including disabled features. */
+export function allCoreFeatureRegistrations(): PluginRegistration[] {
+  return coreFeatures.map((feature) => feature.registration);
+}
+
+/** Return enabled core feature registrations. */
+export function coreFeatureRegistrations(): PluginRegistration[] {
+  return coreFeatures
+    .filter((feature) => feature.isEnabled())
+    .map((feature) => feature.registration);
+}
+
+/** Return enabled core features followed by installed plugins. */
+export function runtimeFeatureRegistrations(
+  plugins: PluginRegistration[],
+): PluginRegistration[] {
+  return [...coreFeatureRegistrations(), ...plugins];
+}
+
+/** Reject a plugin that claims a core feature name. */
+export function assertNoCoreFeatureNameCollisions(
+  plugins: PluginRegistration[],
+): void {
+  const coreNames = new Set(
+    allCoreFeatureRegistrations().map((feature) => feature.manifest.name),
+  );
+  for (const plugin of plugins) {
+    const name = plugin.manifest.name;
+    if (coreNames.has(name)) {
+      throw new Error(`Plugin registration name "${name}" is reserved by core`);
+    }
+  }
+}

packages/junior/src/chat/plugins/agent-hooks.ts

@@ -57,7 +57,10 @@ import { z } from "zod";
 import { workspaceRepoCheckoutPath } from "@/chat/workspaces/checkout-path";
 import { listWorkspaceNamesByRepository } from "@/chat/workspaces/store";
 import { createCodeChangePublisher } from "@/chat/code/publisher";
-import { coreTaskRegistrations } from "@/chat/briefs/registration";
+import {
+  assertNoCoreFeatureNameCollisions,
+  runtimeFeatureRegistrations,
+} from "@/chat/core-features/registration";
 
 /** Signal that a plugin intentionally denied a tool execution. */
 export class PluginHookDeniedError extends Error {
@@ -382,6 +385,7 @@ function logInvalidPromptContributions(args: {
 
 /** Validate plugin identity before it can affect process-wide hooks. */
 export function validatePlugins(plugins: PluginRegistration[]): void {
+  assertNoCoreFeatureNameCollisions(plugins);
   const seen = new Set<string>();
   for (const plugin of plugins) {
     const name = plugin.manifest.name;
@@ -462,7 +466,7 @@ export async function getPluginSystemPromptContributions(
 ): Promise<PluginPromptContributionContext[]> {
   const contributions: PluginPromptContributionContext[] = [];
   let totalChars = 0;
-  for (const plugin of getPlugins()) {
+  for (const plugin of runtimeFeatureRegistrations(getPlugins())) {
     const pluginName = plugin.manifest.name;
     const hook = plugin.hooks?.systemPrompt;
     if (!hook) {
@@ -532,7 +536,7 @@ export async function getPluginUserPromptContributions(args: {
   const contributions: PluginPromptContributionContext[] = [];
   let totalChars = 0;
   let totalContextBytes = 0;
-  for (const plugin of getPlugins()) {
+  for (const plugin of runtimeFeatureRegistrations(getPlugins())) {
     const pluginName = plugin.manifest.name;
     const hook = plugin.hooks?.userPrompt;
     if (!hook) {
@@ -612,7 +616,7 @@ export function getPluginTools(
   sandbox: PluginSandbox = createSandboxCapability(context.workspace),
 ): Record<string, AnyToolDefinition> {
   const tools: Record<string, AnyToolDefinition> = {};
-  for (const plugin of getPlugins()) {
+  for (const plugin of runtimeFeatureRegistrations(getPlugins())) {
     const pluginName = plugin.manifest.name;
     const hook = plugin.hooks?.tools;
     if (!hook) {
@@ -872,7 +876,7 @@ export function getPluginRoutes(options: {
   const seen = new Set<string>();
   const methodsByPath = new Map<string, Set<PluginRouteMethod>>();
 
-  for (const plugin of getPlugins()) {
+  for (const plugin of runtimeFeatureRegistrations(getPlugins())) {
     const pluginName = plugin.manifest.name;
     const hook = plugin.hooks?.routes;
     if (!hook) {
@@ -991,7 +995,7 @@ export function getPluginRoutes(options: {
 export function getPluginApiRoutes(): PluginApiRouteRegistration[] {
   const routes: PluginApiRouteRegistration[] = [];
 
-  for (const plugin of getPlugins()) {
+  for (const plugin of runtimeFeatureRegistrations(getPlugins())) {
     const pluginName = plugin.manifest.name;
     const hook = plugin.hooks?.apiRoutes;
     if (!hook) {
@@ -1356,7 +1360,7 @@ export async function getPluginOperationalReports(
   nowMs: number,
 ): Promise<PluginOperationalReport[]> {
   const reports: PluginOperationalReport[] = [];
-  for (const plugin of [...coreTaskRegistrations(), ...getPlugins()]) {
+  for (const plugin of runtimeFeatureRegistrations(getPlugins())) {
     const pluginName = plugin.manifest.name;
     const hook = plugin.hooks?.operationalReport;
     if (!hook) {

packages/junior/src/chat/plugins/conversation-events.ts

@@ -5,7 +5,7 @@ import type {
   PluginConversationEventValue,
   PluginRegistration,
 } from "@sentry/junior-plugin-api";
-import { briefsTaskRegistration } from "@/chat/briefs/task";
+import { allCoreFeatureRegistrations } from "@/chat/core-features/registration";
 import { getConversationEventStore } from "@/chat/db";
 import { getPlugins } from "./agent-hooks";
 
@@ -80,7 +80,7 @@ export function renderPluginConversationEvent(args: {
   namespace: string;
   version: number;
 }): ConversationEventPresentation | undefined {
-  const plugin = [briefsTaskRegistration, ...getPlugins()].find(
+  const plugin = [...allCoreFeatureRegistrations(), ...getPlugins()].find(
     (candidate) => candidate.manifest.name === args.namespace,
   );
   const definition = plugin?.conversationEvents?.find(

packages/junior/src/chat/plugins/task-runner.ts

@@ -47,7 +47,7 @@ import {
   getTurnRecord,
   type TurnRecord,
 } from "@/chat/task-execution/checkpoint";
-import { coreTaskRegistrations } from "@/chat/briefs/registration";
+import { runtimeFeatureRegistrations } from "@/chat/core-features/registration";
 import { getPlugins } from "./agent-hooks";
 import {
   pluginTaskId,
@@ -442,7 +442,7 @@ function taskPluginContext(
 }
 
 function findPluginTask(message: PluginTaskQueueMessage) {
-  const plugin = [...coreTaskRegistrations(), ...getPlugins()].find(
+  const plugin = runtimeFeatureRegistrations(getPlugins()).find(
     (candidate) => candidate.manifest.name === message.plugin,
   );
   if (!plugin?.tasks || !Object.hasOwn(plugin.tasks, message.name)) {
@@ -458,11 +458,9 @@ export async function scheduleSessionCompletedPluginTasks(
   options: ScheduleSessionCompletedPluginTasksOptions = {},
 ): Promise<void> {
   const coreParams = pluginTaskParamsSchema.parse(params);
-  const taskRegistrations = [
-    ...getPlugins(),
-    ...coreTaskRegistrations(),
-  ].flatMap((plugin) =>
-    Object.keys(plugin.tasks ?? {}).map((name) => ({ name, plugin })),
+  const taskRegistrations = runtimeFeatureRegistrations(getPlugins()).flatMap(
+    (plugin) =>
+      Object.keys(plugin.tasks ?? {}).map((name) => ({ name, plugin })),
   );
   if (taskRegistrations.length === 0) {
     return;

packages/junior/src/chat/plugins/user-pages.ts

@@ -15,11 +15,12 @@ import { getDb } from "@/chat/db";
 import { createPluginLogger } from "@/chat/plugins/logging";
 import { resolveViewerUser } from "@/chat/plugins/viewer";
 import { getPlugins } from "@/chat/plugins/agent-hooks";
+import { runtimeFeatureRegistrations } from "@/chat/core-features/registration";
 
 /** List safe navigation metadata for registered plugin user pages. */
 export function readPluginUserPageLinks(): PluginUserPageLink[] {
   return pluginUserPageLinksSchema.parse(
-    getPlugins().flatMap((plugin) =>
+    runtimeFeatureRegistrations(getPlugins()).flatMap((plugin) =>
       (plugin.userPages ?? []).map((page) => ({
         description: page.description,
         id: page.id,
@@ -50,7 +51,7 @@ export async function readPluginUserPage(input: {
   pluginName: string;
   query: PluginUserPageInput;
 }): Promise<PluginUserPageContent | undefined> {
-  const plugin = getPlugins().find(
+  const plugin = runtimeFeatureRegistrations(getPlugins()).find(
     (candidate) => candidate.manifest.name === input.pluginName,
   );
   const page = plugin?.userPages?.find(

packages/junior/src/cli/plugins.ts

@@ -21,6 +21,7 @@ import {
   validatePluginRegistrations,
 } from "@/chat/plugins/validation";
 import { loadAppPluginSet } from "@/plugin-module";
+import { runtimeFeatureRegistrations } from "@/chat/core-features/registration";
 import {
   pluginCliRegistrationsFromPluginSet,
   pluginCatalogConfigFromPluginSet,
@@ -226,14 +227,17 @@ async function loadPluginRegistrations(args: {
   runtimePlugins: PluginRegistration[];
 }> {
   const pluginSet = args.pluginSet;
+  const cliPlugins = runtimeFeatureRegistrations(
+    pluginCliRegistrationsFromPluginSet(pluginSet),
+  ).filter((registration) => registration.cli);
   if (!pluginSet) {
-    return { cliPlugins: [], runtimePlugins: [] };
+    args.validateConfiguredCommands?.(cliPlugins);
+    return { cliPlugins, runtimePlugins: [] };
   }
 
-  const cliPlugins = pluginCliRegistrationsFromPluginSet(pluginSet);
   const runtimePlugins = pluginRuntimeRegistrationsFromPluginSet(pluginSet);
   const pluginConfig = pluginCatalogConfigFromPluginSet(pluginSet);
-  validatePlugins(runtimePlugins);
+  validatePlugins(pluginSet.registrations);
   const previousPluginCatalogConfig =
     pluginCatalogRuntime.setConfig(pluginConfig);
   try {

packages/junior/tests/unit/core-feature-registration.test.ts

@@ -0,0 +1,41 @@
+import { defineJuniorPlugin } from "@sentry/junior-plugin-api";
+import { afterEach, describe, expect, it } from "vitest";
+import { setBriefsConfig } from "@/chat/briefs/registration";
+import {
+  allCoreFeatureRegistrations,
+  coreFeatureRegistrations,
+} from "@/chat/core-features/registration";
+import { validatePlugins } from "@/chat/plugins/agent-hooks";
+
+const briefsPlugin = defineJuniorPlugin({
+  manifest: {
+    name: "briefs",
+    displayName: "Briefs",
+    description: "Conflicting Briefs plugin",
+  },
+});
+
+afterEach(() => {
+  setBriefsConfig(undefined);
+});
+
+describe("core feature registration", () => {
+  it("enables Briefs from app config but keeps its registration available", () => {
+    expect(coreFeatureRegistrations()).toEqual([]);
+    expect(
+      allCoreFeatureRegistrations().map((feature) => feature.manifest.name),
+    ).toEqual(["briefs"]);
+
+    setBriefsConfig({ enabled: true });
+
+    expect(
+      coreFeatureRegistrations().map((feature) => feature.manifest.name),
+    ).toEqual(["briefs"]);
+  });
+
+  it("reserves core feature names", () => {
+    expect(() => validatePlugins([briefsPlugin])).toThrow(
+      'Plugin registration name "briefs" is reserved by core',
+    );
+  });
+});