@@ -0,0 +1,17 @@
+---
+'@objectstack/platform-objects': minor
+---
+
+fix(platform-objects): a team record no longer lists Sessions with "Sign out other devices" (#24765)
+
+Clause-②: no (narrowing)
+
+<!-- adr-0087: not-required (no-migration-prescription) One shipped object field gains `relatedList: false`, a key it was always free to set. No spec key, authorable spelling, export, type or stored shape is added, removed or renamed, and no stored row or column is read or rewritten, so `objectstack migrate meta` has nothing to rewrite. What narrows is one derived related list on a team's served detail page. The other categories are closed on facts: the package publishes (not unpublished); no ADR-0087 id covers this field (not already-registered); and the change is metadata on a shipped object, not an interface, a type or an export (not runtime-interface-only, type-surface-only or runtime-export-retired). -->
+
+**BREAKING** for a reader of a team's derived related lists only: Setup → Teams → a team → Related no longer lists *Sessions*. Shipped as `minor` under the launch-window convention for accept-set narrowings.
+
+- **Before.** `sys_session.active_team_id` is a lookup to `sys_team` that did not set `relatedList: false`, so every team record derived a Sessions related list. That list carried the session list's only toolbar action, "Sign out other devices", whose confirmation reads "Sign out of every other device where you're currently logged in?". The action signs out the administrator's own other sessions, not the team's.
+- **Now.** `active_team_id` sets `relatedList: false`, so a team record derives no Sessions list. A team's Members and Invitations lists are unchanged.
+- **Unchanged.** The `active_team_id` field, its lookup to `sys_team`, its label and its column: better-auth still writes `activeTeamId` there. A user record's Sessions tab (keyed on `user_id`), where "Sign out other devices" belongs, and the action itself.
+
+**What to do.** Nothing. No team-scoped session action existed to lose.
@@ -234,6 +234,8 @@ export const SysSession = ObjectSchema.create({
       label: 'Active Team',
       required: false,
       group: 'Context',
+      // A team record derives no Sessions list: its only header action signs out the caller's own devices.
+      relatedList: false,
     }),
 
     // ── Client fingerprint ───────────────────────────────────────
 
@@ -0,0 +1,92 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * A team record's page lists no Sessions; a user's page still does.
+ *
+ * `sys_team` declares no record page, so its related lists are DERIVED: every
+ * `lookup` / `master_detail` field whose `reference` is `sys_team` becomes a
+ * related list on the team's detail page unless the field sets
+ * `relatedList: false` (`FieldSchema.relatedList`; the reader is objectui's
+ * `deriveRelatedLists`, cited in `packages/spec/liveness/field.json`).
+ *
+ * `sys_session.active_team_id` used to derive one. That list carried the
+ * session object's only `list_toolbar` action, "Sign out other devices",
+ * which revokes the CALLER's own other sessions — on a team record it read as
+ * a team action and was not one. The field, its lookup and its label stay
+ * (better-auth writes `activeTeamId` into it); only the derived list goes.
+ *
+ * The user's own Sessions list is a curated tab on `SysUserDetailPage`, keyed
+ * on `sys_session.user_id`, and is where that action belongs: pinned unchanged.
+ */
+
+import { describe, expect, it } from 'vitest';
+import * as PlatformObjects from '../index.js';
+import { SysSession } from './sys-session.object.js';
+import { SysUserDetailPage } from '../pages/sys-user.page.js';
+
+type FieldDef = { type?: string; reference?: string; relatedList?: boolean | 'primary'; label?: string };
+type ActionDef = { name?: string; locations?: string[] };
+type ObjectDef = { name?: string; fields?: Record<string, FieldDef>; actions?: ActionDef[] };
+
+const CATALOGUE: ObjectDef[] = [
+  ...new Set(
+    (Object.values(PlatformObjects) as unknown[]).filter(
+      (v): v is ObjectDef =>
+        !!v && typeof v === 'object' && typeof (v as ObjectDef).name === 'string' && !!(v as ObjectDef).fields,
+    ),
+  ),
+];
+
+/** `<child>.<field>` for every relationship field that derives a related list on `parent`. */
+function derivedRelatedLists(parent: string): string[] {
+  const out: string[] = [];
+  for (const obj of CATALOGUE) {
+    for (const [name, field] of Object.entries(obj.fields ?? {})) {
+      if (field.type !== 'lookup' && field.type !== 'master_detail') continue;
+      if (field.reference !== parent || field.relatedList === false) continue;
+      out.push(`${obj.name}.${name}`);
+    }
+  }
+  return out.sort();
+}
+
+describe('sys_team derived related lists (Setup → Teams → a team → Related)', () => {
+  it('exclude sys_session', () => {
+    const lists = derivedRelatedLists('sys_team');
+    expect(lists.filter((l) => l.startsWith('sys_session.'))).toEqual([]);
+    // Guard against over-applying: the team's members are still listed.
+    expect(lists).toContain('sys_team_member.team_id');
+  });
+
+  it('keep sys_session.active_team_id as a lookup to sys_team, suppressed only as a related list', () => {
+    const field = SysSession.fields.active_team_id as FieldDef;
+    expect(field.type).toBe('lookup');
+    expect(field.reference).toBe('sys_team');
+    expect(field.label).toBe('Active Team');
+    expect(field.relatedList).toBe(false);
+  });
+});
+
+describe("the user's own Sessions related list is unchanged", () => {
+  it('SysUserDetailPage lists sys_session by user_id', () => {
+    const lists: Array<{ objectName?: string; relationshipField?: string }> = [];
+    const walk = (node: unknown): void => {
+      if (Array.isArray(node)) return node.forEach(walk);
+      if (!node || typeof node !== 'object') return;
+      const n = node as { type?: string; properties?: { objectName?: string; relationshipField?: string } };
+      if (n.type === 'record:related_list' && n.properties) lists.push(n.properties);
+      Object.values(node).forEach(walk);
+    };
+    walk(SysUserDetailPage);
+    expect(lists).toContainEqual(expect.objectContaining({ objectName: 'sys_session', relationshipField: 'user_id' }));
+  });
+
+  it('sys_session.user_id still derives a related list on sys_user', () => {
+    expect(derivedRelatedLists('sys_user')).toContain('sys_session.user_id');
+  });
+
+  it('"Sign out other devices" stays the session list toolbar action', () => {
+    const action = (SysSession.actions as ActionDef[]).find((a) => a.name === 'revoke_my_other_sessions');
+    expect(action?.locations).toEqual(['list_toolbar']);
+  });
+});