diff --git a/.changeset/17210-oauth-register-name-trap-prose.md b/.changeset/17210-oauth-register-name-trap-prose.md
new file mode 100644
index 0000000000..986ddc0ea5
--- /dev/null
+++ b/.changeset/17210-oauth-register-name-trap-prose.md
@@ -0,0 +1,28 @@
+---
+'@objectstack/client': patch
+---
+
+`oauth.applications.register`'s docblock says where a plain `name` IS honoured, and that it is not this route
+
+A caller who wants to name an OAuth client reaches for `name`. On the route this
+method posts — the provider's `/oauth2/create-client` — that member is not in
+the body schema and is stripped: driven on a real socket, the call answered
+**201** and the value was absent from the response, from `applications.get`,
+from `applications.list`, and `null` in the `sys_oauth_application` row's `name`
+column. Nothing in the answer says so.
+
+The spelling is not wrong everywhere, which is what made it worth writing down:
+`POST /api/v1/auth/sys-oauth-application/register` — the session-required
+ObjectStack mount behind the Console's *Setup → OAuth Applications* form —
+answered **200** to the same body, mapped `name` onto `client_name`, and set
+that column. That mount is `disposition: 'server-only'` in the auth route ledger
+and objectstack#17210 ruled it stays that way, so no SDK method builds its URL.
+
+The docblock now states both halves where the caller reads them: post
+`client_name` to name a client from here, and `redirect_uris` must arrive
+pre-split — the newline-separated-textarea split is the Console wrapper's, not
+this route's.
+
+Docblock only. No method is added, no request or response type changes, and the
+ledger row is untouched — but the text ships inside `dist/*.d.ts` as editor
+hover, so it is a `patch` rather than a no-publish change.
diff --git a/content/docs/protocol/objectui/actions.mdx b/content/docs/protocol/objectui/actions.mdx
index 0e44483483..77c2a7e242 100644
--- a/content/docs/protocol/objectui/actions.mdx
+++ b/content/docs/protocol/objectui/actions.mdx
@@ -435,6 +435,12 @@ resultDialog:
 
 Each `fields[].path` is a dot path into `result.data`. The per-field `format` (`qrcode`, `code-list`, `secret`, `text`, `json`) controls rendering.
 
+#### ⚠️ That `target` is not interchangeable with the SDK's registration door
+
+`POST /api/v1/auth/sys-oauth-application/register` is an **ObjectStack mount written for this form**, and it is what keeps the YAML above this short. It accepts the application's display name as a plain `name` body key — the spelling an author writes as a param — and it splits a newline-separated redirect-URL **textarea** into the `redirect_uris` array the underlying provider schema requires. Both are form-shaped conveniences the mount performs on the action's behalf; the route ledger carries it as `disposition: server-only` (`packages/plugins/plugin-auth/src/auth-route-ledger.ts`) for exactly that reason, and [#17210](https://github.com/objectstack-ai/objectstack/issues/17210) ruled that it stays that way — no SDK method builds this URL.
+
+So do **not** re-point this `target` at the provider's own registration route, `/api/v1/auth/oauth2/create-client` (what `@objectstack/client`'s `oauth.applications.register` posts). Driven on a real socket, the two doors answer the same body differently: the mount above returned **200**, mapped `name` onto `client_name`, and set the `sys_oauth_application` row's `name`; the provider route returned **201** with the value **stripped** — absent from the response, from `oauth.applications.get`, from `oauth.applications.list`, and `null` in that column. An action retargeted there needs its name param renamed to `client_name`, and its redirect URLs split into an array before the post — the textarea param would arrive as one unsplit string.
+
 ## Action Parameters
 
 `params` declares inputs collected from the user before execution. Each entry is an `ActionParam` with two modes:
diff --git a/packages/client/src/index.ts b/packages/client/src/index.ts
index fa47e56119..4a2030cf86 100644
--- a/packages/client/src/index.ts
+++ b/packages/client/src/index.ts
@@ -4038,6 +4038,33 @@ export class ObjectStackClient {
        * router skips SERVER_ONLY endpoints, so over HTTP it answers 404 with a
        * zero-byte body.
        *
+       * ## ⚠️ A plain `name` IS honoured somewhere — not here (#17210)
+       *
+       * There is exactly one door that reads a body member spelled `name`, and
+       * this method does not build it:
+       * `POST /api/v1/auth/sys-oauth-application/register`, the ObjectStack
+       * mount behind the Console's *Setup → OAuth Applications* create form.
+       * The same #15447 round drove both doors on one real socket: that mount
+       * answered **200** to a body spelled `name`, mapped it onto
+       * `client_name`, and the `sys_oauth_application` row's `name` column was
+       * set; this method's route, `/oauth2/create-client`, answered **201**
+       * with the value **stripped** — absent from the response, absent from
+       * `applications.get`, absent from `applications.list`, and `null` in
+       * that same column.
+       *
+       * ⛔ That mount is **not** an SDK door, and it is not withheld by
+       * oversight: it is `disposition: 'server-only'` in the auth route ledger
+       * (`packages/plugins/plugin-auth/src/auth-route-ledger.ts`), a
+       * session-required self-service wrapper written to serve the Console's
+       * form — and #17210 ruled that it **stays** `server-only`, so no SDK
+       * method builds its URL. To name a client from here, post `client_name`.
+       *
+       * The wrapper's other Console-shaped convenience is the same asymmetry's
+       * second half: it splits that form's newline-separated redirect-URL
+       * **textarea** into the array the vendor schema requires. ⛔ This route
+       * performs no such split — `redirect_uris` must arrive **pre-split**,
+       * one entry per URL, which is what an SDK caller holds anyway.
+       *
        * Pinned by `oauth-applications-register-request-members.test.ts`.
        */
       register: async (req: {