diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2286623..e13d648 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -88,3 +88,6 @@ the admin is mounted. The admin provides it; core reads it instead of assuming
   `patchFields`; `EditorIdentity` and `InlineEditRequestContext` are declared.
   Page-event payloads (`onPageMove`'s `PageMovePayload`, and the others by
   documentation) carry an optional `actor`.
+- `EditorIdentity.relation` (`admin` | `editor` | `author`): the admin-tier
+  relation core decided for the editor from the site's role grants, for
+  providers that apply an ownership rule.
diff --git a/src/inline-edit.ts b/src/inline-edit.ts
index 38b4e50..eba6621 100644
--- a/src/inline-edit.ts
+++ b/src/inline-edit.ts
@@ -42,6 +42,13 @@ export interface EditorIdentity {
   username: string;
   /** Every role on the user record (admin-tier roles and content-gating tags mixed). */
   roles: string[];
+  /**
+   * The admin-tier relation this editor holds on the site: `admin` and `editor` may edit any
+   * page, `author` only the pages it created. Decided by core from the site's
+   * `system.role_grants` (a group `staff` mapped to `editor` makes its members `editor`), so a
+   * provider applies ownership rules to this and not to role names.
+   */
+  relation: "admin" | "editor" | "author";
   /** `site`: signed in through the site's own login; `session`: through the `editor.session` provider. */
   source: "site" | "session";
 }