@@ -0,0 +1,18 @@
+---
+'@objectstack/cloud-connection': patch
+---
+
+fix(cloud-connection)!: install-local's cloud branch refuses a package declaring a bare name another package holds (#31296)
+
+Clause-②: no (narrowing) — `POST /api/v1/marketplace/install-local` with a cloud-fetched package (`packageId` + `versionId`) whose register the registry refuses for a bare-name clash answers `422 PLUGIN_REGISTER_FAILED` where it answered `200` with `hotLoaded: false` and wrote the ledger entry. Nothing is widened.
+Metadata-protocol: none
+
+<!-- adr-0087: not-required (no-migration-prescription) no key of any schema is added, removed or re-shaped and no stored row is read differently: the narrowing is one runtime refusal at one door, for one registry refusal the inline branch of the same door already answers 422, and its remedy is the rename the refusal names, so there is nothing for `objectstack migrate meta` to rewrite. A ledger entry an earlier build wrote this way keeps loading at boot, beside the cold boot's warning. -->
+
+**BREAKING** for a cloud-branch install that relied on the lenient answer for a bare-name clash.
+
+- **Before.** The cloud branch refused only the security catalog's environment-held refusal (#25366). A package declaring an item of a bare-name type (a flow, a webhook, a connector, an email template, a dataset, a mapping, a picklist, an API, an object-less action) under a name another installed package or the platform holds was refused by the registry and then ledgered anyway, answering `200` with `hotLoaded: false`. At the next restart the entry loaded before the cold boot sealed the holders, so the boot admitted the clash with one warning, and every consumer resolving the name was served one of the two packages' items by registration order.
+- **Now.** That refusal is answered `422 PLUGIN_REGISTER_FAILED` with the registry's sentence naming both holders and the rename, as the inline branch answers it. Nothing is registered or written, and an installed earlier version stays registered and ledgered. The door recognises the registry's refusal by its own brand, never by a list of types, so a type the rule covers later is refused the same way.
+- **Unchanged.** Any other register failure on the cloud branch keeps the lenient answer (`200`, `hotLoaded: false`, `hotLoadError`). An environment-held security catalog name is still refused `422`.
+
+**The remedy.** Rename the item in the incoming package (the refusal names the namespaced rename), rename it in the package that holds it, or uninstall that package, then install again.
@@ -0,0 +1,300 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * #31296 — the cloud-fetched branch of `POST /api/v1/marketplace/install-local`
+ * refuses a package declaring a bare name another package holds (the #30803
+ * series: a flow, a webhook, a dataset, …), the way the inline branch does,
+ * before anything is written.
+ *
+ * ## What was wrong
+ *
+ * The registry's package door refuses such a package ahead of every one of its
+ * writes (`BareNameConflictError`, `bare-name-one-holder.ts` in
+ * `@objectstack/objectql`). The inline branch answered that refusal `422`. The
+ * cloud-fetched branch recognised only the security catalog's
+ * environment-held refusal (#25366) and took #22695's lenient path for this
+ * one: it wrote the ledger entry and answered `200` with `hotLoaded: false`,
+ * "loads at the next restart". At that restart the entry is rehydrated BEFORE
+ * the cold boot seals the holders, so the boot admits the clash with one
+ * warning, and every consumer resolving the name is served one of the two
+ * packages' items by registration order — the condition the rule refuses.
+ *
+ * ## What is real here
+ *
+ * The judge is real: an `ObjectKernel` with `ObjectQLPlugin` supplies the
+ * `manifest` service over the real `SchemaRegistry`, booted to
+ * `kernel:bootstrapped`, so the holders are sealed and the refusal under test
+ * is the one production raises. The holding package is installed through the
+ * same door. The side readers that run after the ledger write (binder,
+ * translations, seeds) are recorders; they are not what is pinned. The cloud
+ * leg is a stubbed `fetch`.
+ *
+ * ## What these cases pin
+ *
+ *   - a fresh cloud-fetched install and a cloud-fetched upgrade, each declaring
+ *     a flow name another package holds: `422 PLUGIN_REGISTER_FAILED` in the
+ *     declared envelope, both holders and the rename named, the registry and
+ *     the ledger exactly as before the call, the holder's flow still the
+ *     holder's;
+ *   - CONTROL, an environment-held security catalog name: the same `422` it
+ *     answered before (#25366; its full matrix lives in
+ *     `marketplace-install-local-catalog-name-collision.test.ts`);
+ *   - CONTROL, the same package declaring a flow name nobody holds: `200`,
+ *     `hotLoaded: true`, registered and ledgered.
+ *
+ * A register failure that is NOT a registry refusal keeps #22695's lenient
+ * answer; `marketplace-install-local-hot-loaded.test.ts` pins that.
+ */
+
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { BaseResponseSchema, ApiErrorSchema, envelopeViolations } from '@objectstack/spec/api';
+// The plugin reaches `@objectstack/runtime` through a lazy `import()`; its first
+// load is paid here, at module top, never inside a clocked `it`.
+import '@objectstack/runtime';
+import { ObjectKernel } from '@objectstack/core';
+import { ObjectQLPlugin, type ObjectQL } from '@objectstack/objectql';
+import { MarketplaceInstallLocalPlugin } from './marketplace-install-local-plugin.js';
+import { LocalManifestSource } from './local-manifest-source.js';
+import { installerAuthService, withInstallerGrants } from './install-local-principal.fixtures.js';
+
+type Bag = Record<string, any>;
+type Handler = (c: any) => Promise<any>;
+
+const ROUTE = '/api/v1/marketplace/install-local';
+const CLOUD_URL = 'http://cloud.test';
+
+/** The package already holding the flow name, installed first. */
+const HOLDER_ID = 'com.acme.dispatch';
+/** The package the cloud-fetched install asks for. */
+const INCOMING_ID = 'com.acme.routing';
+/** The flow name both declare. */
+const HELD_FLOW = 'assign_technician';
+/** CONTROL: a flow name nobody holds. */
+const FREE_FLOW = 'reassign_technician';
+
+const flow = (name: string, tag: string): Bag => ({
+    name,
+    label: `${tag} flow`,
+    type: 'autolaunched',
+    status: 'active',
+    nodes: [{ id: 'start', type: 'start', label: 'Start' }],
+    edges: [],
+});
+
+/** A package version whose namespace is its id's last segment, so the refusal's rename is `NAMESPACE_NAME`. */
+const packageVersion = (id: string, version: string, flows: string[], extra: Bag = {}): Bag => {
+    const ns = id.split('.').pop()!;
+    return {
+        id,
+        name: ns,
+        namespace: ns,
+        type: 'app',
+        version,
+        flows: flows.map((name) => flow(name, ns)),
+        ...extra,
+    };
+};
+
+let dir: string;
+const kernels: ObjectKernel[] = [];
+beforeEach(() => { dir = mkdtempSync(join(tmpdir(), 'mil-bare-name-conflict-')); });
+afterEach(async () => {
+    while (kernels.length) {
+        const k = kernels.pop()!;
+        if (k.getState() === 'running') await k.shutdown();
+    }
+    rmSync(dir, { recursive: true, force: true });
+    vi.unstubAllGlobals();
+    vi.unstubAllEnvs();
+    vi.restoreAllMocks();
+});
+
+/**
+ * Serve package versions from the cloud leg, by the `versionId` the install
+ * asks for; the public fast-path is off and a service key is set, so the
+ * credential read never reaches the developer's own on-disk binding.
+ */
+function serveVersions(versions: Record<string, Bag>) {
+    vi.stubEnv('OS_MARKETPLACE_PUBLIC_BASE_URL', 'off');
+    vi.stubEnv('OS_CLOUD_API_KEY', 'svc-test-key');
+    vi.stubGlobal('fetch', vi.fn(async (url: string) => {
+        const versionId = decodeURIComponent(String(url).split('/versions/')[1]?.split('/')[0] ?? '');
+        const manifest = versions[versionId];
+        if (!manifest) return new Response('not found', { status: 404 });
+        return new Response(
+            JSON.stringify({ data: { manifest, version: manifest.version, version_id: versionId } }),
+            { status: 200, headers: { 'Content-Type': 'application/json' } },
+        );
+    }));
+}
+
+/** The plugin over a REAL engine's `manifest` service and registry, booted (holders sealed) to `kernel:ready`. */
+async function bootPlugin() {
+    const kernel = new ObjectKernel({ logger: { level: 'silent' }, gracefulShutdown: false } as never);
+    kernels.push(kernel);
+    await kernel.use(new ObjectQLPlugin());
+    await kernel.bootstrap();
+    const ql = kernel.getService<ObjectQL>('objectql');
+    ql.registry.logLevel = 'silent';
+
+    const routes = new Map<string, Handler>();
+    const rawApp = {
+        get: (p: string, h: Handler) => routes.set(`GET ${p}`, h),
+        post: (p: string, h: Handler) => routes.set(`POST ${p}`, h),
+        delete: (p: string, h: Handler) => routes.set(`DELETE ${p}`, h),
+    };
+    const hooks = new Map<string, () => Promise<void>>();
+    const logger = { info: vi.fn(), warn: vi.fn(), error: vi.fn(), debug: vi.fn() };
+    const services: Record<string, unknown> = {
+        manifest: kernel.getService('manifest'),
+        auth: installerAuthService(),
+        objectql: withInstallerGrants({
+            convertPackageBodyForward: (body: unknown) => ql.convertPackageBodyForward(body),
+            registry: ql.registry,
+            syncSchemas: async () => undefined,
+        }),
+    };
+    const ctx = {
+        hook: (e: string, h: () => Promise<void>) => hooks.set(e, h),
+        getService: (name: string) => {
+            if (name === 'http-server') return { getRawApp: () => rawApp };
+            if (!(name in services)) throw new Error(`no ${name}`);
+            return services[name];
+        },
+        logger,
+    };
+
+    const plugin = new MarketplaceInstallLocalPlugin({ controlPlaneUrl: CLOUD_URL, storageDir: dir });
+    const p = plugin as unknown as Record<string, unknown>;
+    p.bindArtifactHandlers = async () => undefined;
+    p.applySideEffects = async () => ({ translationsLoaded: 0, seeded: { mode: 'none' } });
+
+    await plugin.start(ctx as never);
+    await hooks.get('kernel:ready')?.();
+
+    const install = async (body: Bag) => {
+        const json = vi.fn((payload: any, status?: number) => ({ payload, status: status ?? 200 }));
+        return routes.get(`POST ${ROUTE}`)!({
+            req: {
+                url: `http://localhost:3000${ROUTE}`,
+                raw: new Request(`http://localhost:3000${ROUTE}`),
+                json: async () => body,
+                param: () => undefined,
+            },
+            json,
+        });
+    };
+    /** The cloud-fetched branch: a `packageId` + `versionId` body, the manifest downloaded from the control plane. */
+    const installFromCloud = (versionId: string) => install({ packageId: 'pkg_acme_routing', versionId });
+    /** The holder, through the same door's inline branch. */
+    const installHolder = async () => {
+        const res = await install({ manifest: packageVersion(HOLDER_ID, '1.0.0', [HELD_FLOW]) });
+        expect(res.status, JSON.stringify(res.payload)).toBe(200);
+    };
+    return { ql, install, installFromCloud, installHolder };
+}
+
+/** Every ledger entry, read off disk. */
+const ledger = () => {
+    const source = new LocalManifestSource(dir);
+    return { holder: source.read(HOLDER_ID).entry, incoming: source.read(INCOMING_ID).entry };
+};
+
+/** The holder's flow is still the holder's: the registry serves its item under the bare name. */
+function expectHolderFlowKept(ql: ObjectQL) {
+    expect(ql.registry.getItem<Bag>('flow', HELD_FLOW)?.label).toBe('dispatch flow');
+}
+
+function expectBareNameRefusal(res: any) {
+    expect(res.status, JSON.stringify(res.payload)).toBe(422);
+    expect(BaseResponseSchema.safeParse(res.payload).success).toBe(true);
+    expect(envelopeViolations(res.payload)).toEqual([]);
+    expect(ApiErrorSchema.safeParse(res.payload.error).success).toBe(true);
+    expect(res.payload.success).toBe(false);
+    expect(res.payload.error.code).toBe('PLUGIN_REGISTER_FAILED');
+    // The registry's own sentence: both holders, the name, and the rename.
+    expect(res.payload.error.message).toContain(`package "${INCOMING_ID}"`);
+    expect(res.payload.error.message).toContain(`package "${HOLDER_ID}"`);
+    expect(res.payload.error.message).toContain(`"${HELD_FLOW}"`);
+    expect(res.payload.error.message).toContain(`"routing_${HELD_FLOW}"`);
+}
+
+describe('install-local cloud branch refuses a package declaring a bare name another package holds, before any write', () => {
+    const versions = {
+        'v1-free': packageVersion(INCOMING_ID, '1.0.0', [FREE_FLOW]),
+        'v1-held': packageVersion(INCOMING_ID, '1.0.0', [HELD_FLOW]),
+        'v2-held': packageVersion(INCOMING_ID, '2.0.0', [FREE_FLOW, HELD_FLOW]),
+    };
+
+    it('a fresh install is refused: 422 naming both holders and the rename, nothing registered or ledgered', async () => {
+        serveVersions(versions);
+        const { ql, installFromCloud, installHolder } = await bootPlugin();
+        await installHolder();
+        const before = ledger();
+
+        const res = await installFromCloud('v1-held');
+
+        expectBareNameRefusal(res);
+        expect(res.payload.data).toBeUndefined();
+        expect(ql.registry.getPackage(INCOMING_ID)).toBeUndefined();
+        expect(ledger()).toEqual(before);
+        expect(ledger().incoming).toBeNull();
+        expectHolderFlowKept(ql);
+    });
+
+    it('an upgrade is refused: 422, the installed version still registered and ledgered', async () => {
+        serveVersions(versions);
+        const { ql, installFromCloud, installHolder } = await bootPlugin();
+        await installHolder();
+        const first = await installFromCloud('v1-free');
+        expect(first.status, JSON.stringify(first.payload)).toBe(200);
+        expect(first.payload.data.hotLoaded).toBe(true);
+        const before = ledger();
+
+        const res = await installFromCloud('v2-held');
+
+        expectBareNameRefusal(res);
+        expect(ql.registry.getPackage(INCOMING_ID)?.manifest?.version).toBe('1.0.0');
+        expect(ledger()).toEqual(before);
+        expect(ledger().incoming?.version).toBe('1.0.0');
+        expectHolderFlowKept(ql);
+    });
+
+    it('CONTROL — an environment-held security catalog name keeps its answer: 422 naming the environment catalog', async () => {
+        serveVersions({
+            'v1-cloned': packageVersion(INCOMING_ID, '1.0.0', [], {
+                permissions: [{ name: 'acme_dispatcher_lite', label: 'acme_dispatcher_lite', objects: {} }],
+            }),
+        });
+        const { ql, installFromCloud } = await bootPlugin();
+        // The environment's item, as `sys_metadata` hydration registers it: the bare slot, no package.
+        ql.registry.registerItem('permission', { name: 'acme_dispatcher_lite', label: 'customer clone', objects: {} });
+
+        const res = await installFromCloud('v1-cloned');
+
+        expect(res.status, JSON.stringify(res.payload)).toBe(422);
+        expect(res.payload.error.code).toBe('PLUGIN_REGISTER_FAILED');
+        expect(res.payload.error.message).toContain('the environment catalog');
+        expect(ql.registry.getPackage(INCOMING_ID)).toBeUndefined();
+        expect(ledger().incoming).toBeNull();
+    });
+
+    it('CONTROL — the same package declaring a flow name nobody holds installs: 200, hot-loaded, ledgered', async () => {
+        serveVersions(versions);
+        const { ql, installFromCloud, installHolder } = await bootPlugin();
+        await installHolder();
+
+        const res = await installFromCloud('v1-free');
+
+        expect(res.status, JSON.stringify(res.payload)).toBe(200);
+        expect(res.payload.data.hotLoaded).toBe(true);
+        expect(res.payload.data.hotLoadError).toBeUndefined();
+        expect(ql.registry.getPackage(INCOMING_ID)?.manifest?.version).toBe('1.0.0');
+        expect(ledger().incoming?.version).toBe('1.0.0');
+        expect(ql.registry.getItem<Bag>('flow', FREE_FLOW)?.label).toBe('routing flow');
+        expectHolderFlowKept(ql);
+    });
+});