@@ -0,0 +1,14 @@
+---
+'@objectstack/cli': patch
+---
+
+fix(cli): `os create plugin NAME --in-repo` scaffolds extend `tsconfig.base.json`, so `tsc` reaches the scaffold's own `src/`
+
+Clause-②: no
+Metadata-protocol: none
+
+- **Before.** The in-repo plugin's `tsconfig.json` extended the monorepo root `tsconfig.json`. That file is the type-check program for `scripts/`, and its `exclude` (`packages`, `apps`, `examples`, `ui`) resolves against the root, so a scaffold under `packages/plugins/` inherited it and matched none of its own files: `tsc` stopped with TS18003, "No inputs were found".
+- **After.** The emitted `tsconfig.json` extends `tsconfig.base.json`, the file every package in the monorepo extends, declares `types: ["node"]` and its own `exclude: ["dist", "node_modules"]`, the same shape as a sibling such as `plugin-email`. `tsc --showConfig` for the scaffold and for `plugin-email` differs only in each package's own file list.
+- The default (standalone) placement is unchanged.
+
+What to do: nothing for new scaffolds. An in-repo plugin scaffolded earlier: change its `tsconfig.json` `extends` from `../../../tsconfig.json` to `../../../tsconfig.base.json`, and add `"types": ["node"]` and `"exclude": ["dist", "node_modules"]`.
@@ -73,9 +73,10 @@
  *                            `private`, and the project lands in the
  *                            developer's own directory.
  *   `in-repo`     (--in-repo) the platform-work shape: `workspace:*` deps, a
- *                            `tsconfig.json` that extends this repo's root
- *                            config, a publishable `@objectstack/plugin-<name>`
- *                            landing under `packages/plugins/`. Explicit and
+ *                            `tsconfig.json` that extends this repo's shared
+ *                            `tsconfig.base.json`, a publishable
+ *                            `@objectstack/plugin-<name>` landing under
+ *                            `packages/plugins/`. Explicit and
  *                            documented, never the default — its output
  *                            installs nowhere else.
  *
@@ -168,15 +169,21 @@ export function objectstackDependencySpec(placement: ScaffoldPlacement): string
 }
 
 /**
- * The `extends` an in-repo scaffold needs to reach this repo's root
- * `tsconfig.json`, DERIVED from where the template lands rather than written
- * down. Writing it down is how the `plugin` template came to declare
- * `'../../tsconfig.json'` from a directory two levels below `packages/`, which
- * resolves to a file that does not exist.
+ * The `extends` an in-repo scaffold needs to reach this repo's shared
+ * `tsconfig.base.json` — the file every package here extends — DERIVED from
+ * where the template lands rather than written down. Writing it down is how the
+ * `plugin` template came to declare `'../../tsconfig.json'` from a directory two
+ * levels below `packages/`, which resolves to a file that does not exist.
+ *
+ * ⛔ Never the root `tsconfig.json`: that is the type-check program for
+ * `scripts/` and the top-level configs, and its `exclude` (`packages`, `apps`,
+ * `examples`, `ui`) resolves against the root, so a scaffold that inherited it
+ * matched none of its own `src/` — `tsc` stopped with TS18003, "No inputs were
+ * found".
  */
-export function rootTsconfigExtends(inRepoDir: string, projectDirName: string): string {
+export function baseTsconfigExtends(inRepoDir: string, projectDirName: string): string {
   const depth = path.posix.join(inRepoDir, projectDirName).split('/').filter(Boolean).length;
-  return `${'../'.repeat(depth)}tsconfig.json`;
+  return `${'../'.repeat(depth)}tsconfig.base.json`;
 }
 
 /** A rendered file: JSON objects are stringified on write, strings land as-is. */
@@ -387,7 +394,7 @@ export const templates: Record<string, CreateTemplate> = {
           // `tsc` emits ES modules under the compiler options below, so the
           // manifest has to declare the project as ESM or Node refuses the
           // emitted `dist/index.js`. The in-repo placement inherits its module
-          // semantics from the root config it extends, so it does not.
+          // semantics from the shared base config it extends, so it does not.
           ...(standalone ? { type: 'module' } : {}),
           main: 'dist/index.js',
           types: 'dist/index.d.ts',
@@ -432,12 +439,18 @@ export const templates: Record<string, CreateTemplate> = {
                 include: SCAFFOLD_TSCONFIG_INCLUDE_SRC_ONLY,
               })
             : {
-                extends: rootTsconfigExtends(PLUGIN_IN_REPO_DIR, pluginDirName(name)),
+                // The shape a sibling under `packages/plugins/` declares
+                // (`plugin-email` is one): the shared base, Node's types, and
+                // an `exclude` of its own, so nothing it inherits resolves
+                // against another directory.
+                extends: baseTsconfigExtends(PLUGIN_IN_REPO_DIR, pluginDirName(name)),
                 compilerOptions: {
                   outDir: 'dist',
                   rootDir: 'src',
+                  types: ['node'],
                 },
                 include: ['src/**/*'],
+                exclude: ['dist', 'node_modules'],
               },
         // The config `build` and `dev` compile with (#25175). `tsconfig.json`
         // includes all of `src/`, the starter test with it, so `typecheck`
 
@@ -46,7 +46,7 @@ import {
   templates,
   emittedPackageName,
   objectstackDependencySpec,
-  rootTsconfigExtends,
+  baseTsconfigExtends,
   DEFAULT_PLACEMENT,
   type ScaffoldPlacement,
 } from '../src/commands/create.js';
@@ -191,7 +191,7 @@ describe.each(TEMPLATE_KEYS)('os create %s --in-repo — the platform-work emiss
     expect(objectstackDependencySpec('in-repo')).toBe('workspace:*');
   });
 
-  it('extends a tsconfig that resolves to the monorepo ROOT from where it lands', () => {
+  it('extends a tsconfig that resolves to the monorepo root from where it lands', () => {
     const t = templates[key];
     const cfg = tsconfig(key, 'in-repo');
     expect(cfg.extends, `${key}: --in-repo tsconfig extends nothing`).toBeTruthy();
@@ -201,7 +201,19 @@ describe.each(TEMPLATE_KEYS)('os create %s --in-repo — the platform-work emiss
     // arithmetic, not a transcription: a template that moves takes its own
     // `extends` with it.
     const landedIn = `${t.inRepoDir}/${t.dirName(PROJECT)}`;
-    expect(normalizeJoin(landedIn, cfg.extends)).toBe('tsconfig.json');
+    expect(normalizeJoin(landedIn, cfg.extends)).toBe('tsconfig.base.json');
+  });
+
+  it('extends the shared base, never the root scripts/ program, and owns its exclude', () => {
+    const cfg = tsconfig(key, 'in-repo');
+    // The root `tsconfig.json` is the type-check program for `scripts/`; its
+    // `exclude` names `packages`, resolved against the ROOT, so a scaffold
+    // under `packages/plugins/` that inherited it matched none of its own
+    // `src/` and `tsc` stopped with TS18003. The base declares no `exclude`;
+    // the scaffold's own one keeps it that way if the base ever grows one.
+    expect(cfg.extends).toMatch(/(^|\/)tsconfig\.base\.json$/);
+    expect(cfg.exclude, `${key}: --in-repo tsconfig inherits its exclude`).toEqual(['dist', 'node_modules']);
+    expect(cfg.compilerOptions?.types).toEqual(['node']);
   });
 
   it('emits no pnpm-workspace.yaml, which would sever the workspace it joins', () => {
@@ -319,10 +331,10 @@ describe('os create plugin: the emitted package name follows the placement (#155
   });
 });
 
-describe('rootTsconfigExtends derives the ascent from where a template lands', () => {
+describe('baseTsconfigExtends derives the ascent from where a template lands', () => {
   it('counts the project directory itself', () => {
-    expect(rootTsconfigExtends('packages/plugins', 'plugin-x')).toBe('../../../tsconfig.json');
-    expect(rootTsconfigExtends('examples', 'my-app')).toBe('../../tsconfig.json');
+    expect(baseTsconfigExtends('packages/plugins', 'plugin-x')).toBe('../../../tsconfig.base.json');
+    expect(baseTsconfigExtends('examples', 'my-app')).toBe('../../tsconfig.base.json');
   });
 });
 
 
@@ -266,9 +266,9 @@ const MONOREPO_ONLY = [
   // and `defineTemplate`'s `files` getter — the map `renderAll()` reads below
   // — is `filesFor(DEFAULT_PLACEMENT)`, i.e. `standalone`, whose emitted
   // `tsconfig.json` is self-contained. The one legitimate escaping `../` this
-  // package can produce, `rootTsconfigExtends`, is emitted ONLY on the
+  // package can produce, `baseTsconfigExtends`, is emitted ONLY on the
   // `in-repo` branch and so is never in this sweep. Measured: `filesFor`
-  // `('in-repo')` yields `"../../../tsconfig.json"`; `template.files` and
+  // `('in-repo')` yields `"../../../tsconfig.base.json"`; `template.files` and
   // `filesFor('standalone')` yield no `../` at all.
   //
   // ⚠️ THAT IS THE POPULATION ARGUMENT, NOT A PROPERTY OF THE PATTERN, and the
@@ -282,7 +282,7 @@ const MONOREPO_ONLY = [
   // So there are TWO conditions to re-read this on, not one, and the second is
   // the likelier:
   //   1. the population widens to the `in-repo` placement, which emits
-  //      `rootTsconfigExtends`; or
+  //      `baseTsconfigExtends`; or
   //   2. a template grows an intra-project relative climb — an emitted source
   //      file nested deeply enough to reach back up toward its own project
   //      root. This needs NO placement change at all.