docs(kernel): name the registry slot on every runtime-services page, and gate it

content/docs/kernel/runtime-services/audit-service.mdx

@@ -7,6 +7,7 @@ description: Write ingress for audit events that are not CRUD — today, auth se
 
 - **Stability:** `experimental`
 - **Canonical source:** `packages/plugins/plugin-audit/src/auth-event-audit.ts`
+- **Registry slot:** `audit` — resolve with `ctx.getService('audit')`.
 
 `services.audit` is the kernel service slot that `@objectstack/plugin-audit` registers
 during `init()`. It is the **write ingress for audit events that are not CRUD** — today,

content/docs/kernel/runtime-services/data-service.mdx

@@ -9,6 +9,7 @@ description: CRUD runtime helper API for records (`query`, `get`, `find`, `creat
 - **Canonical source:** `packages/client/src/index.ts` — the `ObjectStackClient.data`
  surface (see [Canonical source](#canonical-source) for why this page names the SDK
  rather than a `contracts/*-service.ts` interface)
+- **Registry slot:** `data` — resolve with `ctx.getService('data')`.
 
 <Callout type="warn" title="Who holds this binding — a hook does not">
 

content/docs/kernel/runtime-services/email-service.mdx

@@ -7,6 +7,7 @@ description: Outbound email delivery and template rendering APIs.
 
 - **Stability:** `stable`
 - **Canonical source:** `packages/spec/src/contracts/email-service.ts`
+- **Registry slot:** `email` — resolve with `ctx.getService('email')`.
 
 ## Methods
 

content/docs/kernel/runtime-services/index.mdx

@@ -12,6 +12,15 @@ repo's runtime, hook bodies reach scoped data operations through `ctx.api`,
 while plugin code resolves any registered service through `ctx.getService(...)` —
 a literal `services.*` object is not injected into hook contexts by the open
 framework today. Managed runtimes provide the `services.*` binding directly.
+
+**`services.*` is the accessor spelling, not necessarily the registry slot.** The name
+after `services.` is what this chapter documents each surface under; the string you pass
+to `ctx.getService(...)` is the slot the implementation is registered by. They are the
+same word for every service below **except storage**, whose slot is `file-storage`
+(there is no `storage` alias — see
+[`services.storage`](/docs/kernel/runtime-services/storage-service)). Each page states
+its own slot in a **Registry slot** bullet; `scripts/check-runtime-services-index.mjs`
+holds those to a real `registerService` call.
 </Callout>
 
 This chapter documents the runtime `services.*` APIs used in hook/action/flow/plugin code:

content/docs/kernel/runtime-services/queue-service.mdx

@@ -7,6 +7,7 @@ description: Async queue publish/subscribe and DLQ operations.
 
 - **Stability:** `stable`
 - **Canonical source:** `packages/spec/src/contracts/queue-service.ts`
+- **Registry slot:** `queue` — resolve with `ctx.getService('queue')`.
 
 ## Methods
 

content/docs/kernel/runtime-services/settings-service.mdx

@@ -7,6 +7,7 @@ description: Namespace-based configuration service with OS env/global/tenant/use
 
 - **Stability:** `stable`
 - **Canonical source:** `packages/services/service-settings/src/settings-service.ts`
+- **Registry slot:** `settings` — resolve with `ctx.getService('settings')`.
 
 ## Key Methods
 

content/docs/kernel/runtime-services/sharing-service.mdx

@@ -7,6 +7,7 @@ description: Record-level sharing and editability checks.
 
 - **Stability:** `stable`
 - **Canonical source:** `packages/spec/src/contracts/sharing-service.ts`
+- **Registry slot:** `sharing` — resolve with `ctx.getService('sharing')`.
 
 ## Methods
 

content/docs/kernel/runtime-services/sms-service.mdx

@@ -7,6 +7,7 @@ description: Outbound SMS delivery through pluggable providers (Aliyun SMS, Twil
 
 - **Stability:** `stable`
 - **Canonical source:** `packages/spec/src/contracts/sms-service.ts`
+- **Registry slot:** `sms` — resolve with `ctx.getService('sms')`.
 
 ## Methods
 

content/docs/kernel/runtime-services/storage-service.mdx

@@ -7,6 +7,46 @@ description: File/object storage contract for upload/download and presigned URL
 
 - **Stability:** `stable`
 - **Canonical source:** `packages/spec/src/contracts/storage-service.ts`
+- **Registry slot:** `file-storage` — **not** `storage`; resolve with
+ `ctx.getService('file-storage')`. See [Accessor name vs registry
+ slot](#accessor-name-vs-registry-slot).
+
+## Accessor name vs registry slot
+
+`services.storage` is this chapter's **accessor spelling** — the name the contract surface
+is documented under. The **registry slot** is the string the kernel actually keys the
+implementation by, and for storage the two differ:
+
+| | value |
+|:--|:--|
+| Documented accessor | `services.storage` |
+| Registry slot | `file-storage` |
+| Resolve with | `ctx.getService('file-storage')` |
+
+This is the **only** service in this chapter where they differ; for the other seven the
+accessor and the slot are the same word. There is no `storage` alias — nothing calls
+`registerService('storage', ...)` anywhere in the platform — so resolving the accessor
+spelling throws rather than returning an empty value:
+
+```ts
+ctx.getService('storage'); // ✗ throws: [Kernel] Service 'storage' not found
+ctx.getService('file-storage'); // ✓ the IStorageService documented below
+```
+
+`file-storage` is the canonical spelling, not an implementation detail: it is the member
+listed in `CoreServiceName` (`packages/spec/src/system/core-services.zod.ts`),
+`CORE_SERVICE_PROVIDER` maps it to `@objectstack/service-storage`, and it is the key the
+`/api/v1/discovery` document reports this service's availability under.
+
+<Callout type="warn" title="Not this: the client SDK storage accessor">
+A second `storage` accessor exists and is easy to reach for by mistake.
+`ObjectStackClient.storage` (`packages/client/src/index.ts`) is the **browser/HTTP client**
+surface — `upload(file, scope)`, `getDownloadUrl(fileId)`, `getPresignedUrl(req)`,
+`initChunkedUpload(req)` — which calls `/api/v1/storage` over the wire. It is a different
+shape from the server-side `IStorageService` documented on this page, which takes storage
+**keys** and returns `Buffer`s. Neither one is reachable through
+`ctx.getService('storage')`.
+</Callout>
 
 ## Core Methods