diff --git a/packages/platform-objects/src/identity/sys-user.object.ts b/packages/platform-objects/src/identity/sys-user.object.ts
index 8a603e822b..850d58ff26 100644
--- a/packages/platform-objects/src/identity/sys-user.object.ts
+++ b/packages/platform-objects/src/identity/sys-user.object.ts
@@ -395,6 +395,19 @@ export const SysUser = ObjectSchema.create({
       description: 'When set, the ban auto-clears at this time.',
     }),
 
+    ai_access: Field.boolean({
+      label: 'AI Access',
+      defaultValue: false,
+      group: 'Admin',
+      description:
+        'Whether this user holds an AI seat — grants access to the in-UI AI ' +
+        'agents (build / ask). The framework synthesizes the `ai_seat` ' +
+        'capability from this flag (plugin-hono-server resolveCtx). Assignment ' +
+        'is capped by the licensed / purchased seat count (enforced by ' +
+        '@objectstack/security-enterprise AiSeatPlugin). Owned by objectql ' +
+        '(better-auth is oblivious to this column).',
+    }),
+
     // ── Profile ──────────────────────────────────────────────────
     image: Field.url({
       label: 'Profile Image',
diff --git a/packages/plugins/plugin-auth/src/auth-manager.ts b/packages/plugins/plugin-auth/src/auth-manager.ts
index 30f056cfc4..c0764915fd 100644
--- a/packages/plugins/plugin-auth/src/auth-manager.ts
+++ b/packages/plugins/plugin-auth/src/auth-manager.ts
@@ -324,6 +324,14 @@ export class AuthManager {
       // createAdapterFactory.
       user: {
         ...AUTH_USER_CONFIG,
+        // NOTE: the env-side AI-seat marker `sys_user.ai_access` is deliberately
+        // NOT declared as a better-auth additionalField. sys_user is a
+        // better-auth-MANAGED table and better-auth SELECTs explicit columns, so
+        // declaring it here would make getSession query a column that may not
+        // exist on every env yet → broken auth. Instead the column is owned by
+        // the objectql `SysUser` object def (provisioned by boot schema-sync)
+        // and read by a GUARDED system query in resolveCtx (can only no-op,
+        // never break auth). better-auth stays oblivious to the extra column.
       },
       account: {
         ...AUTH_ACCOUNT_CONFIG,
diff --git a/packages/plugins/plugin-hono-server/src/hono-plugin.ts b/packages/plugins/plugin-hono-server/src/hono-plugin.ts
index 4d13aebb54..7b307c74e9 100644
--- a/packages/plugins/plugin-hono-server/src/hono-plugin.ts
+++ b/packages/plugins/plugin-hono-server/src/hono-plugin.ts
@@ -490,6 +490,30 @@ export class HonoServerPlugin implements Plugin {
                         /* fall back to self-only */
                     }
                 }
+                // Env-side AI-seat marker (simple model). The single-org env
+                // DB has no permission-set/org dimension for this — the seat is
+                // the boolean `sys_user.ai_access`. Read it with a GUARDED system
+                // query (NOT a better-auth additionalField: sys_user is
+                // better-auth-managed and better-auth SELECTs explicit columns,
+                // so an additionalField would make getSession query a possibly-
+                // missing column → broken auth; a guarded read can only no-op).
+                // When true, synthesize the `ai_seat` capability so the per-agent
+                // gate (evaluateAgentAccess → requires `ai_seat`) admits the user
+                // with no permission-set grant. Absent/false/missing-column →
+                // no synthesis (deny, as before).
+                if (!permissions.includes('ai_seat')) {
+                    try {
+                        const ql = getObjectQL();
+                        const sysCtx = { context: { isSystem: true } };
+                        const uRows = await ql?.find?.(
+                            'sys_user',
+                            { where: { id: userId }, limit: 1, ...sysCtx } as any,
+                        ).catch(() => []);
+                        if ((uRows?.[0] as any)?.ai_access === true) permissions.push('ai_seat');
+                    } catch {
+                        /* no ai_access column / query failed → no seat (safe) */
+                    }
+                }
                 return {
                     userId,
                     tenantId,