diff --git a/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_driver/main_loop_tests.rs b/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_driver/main_loop_tests.rs
index 5175b1eca..443c49466 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_driver/main_loop_tests.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_driver/main_loop_tests.rs
@@ -685,6 +685,53 @@ async fn legacy_game_chat_dynamic_art_retry_runs_are_read_only_and_fail_closed()
     assert!(!root.join("assets/forged-retry-must-not-write.txt").exists());
 }
 
+#[test]
+fn non_delegated_art_sources_stay_out_of_game_chat_art_gate() {
+    for source in ["agent-ready-task-scheduler", "agent-background-task"] {
+        let temporary = tempfile::tempdir().expect("create non-delegated art root");
+        let root = temporary.path().join("project");
+        init_local_game_project_at(&root, "non-delegated-art", "非委派美术来源")
+            .expect("init non-delegated art project");
+        let run_id = format!("non-delegated-art-{source}");
+        start_game_creator_agent_runtime_task_at(
+            &root,
+            "art-director",
+            "非委派来源不得进入 game-chat 美术谱系门",
+            &run_id,
+            source,
+            "校验工具边界",
+            vec!["非委派来源不受美术门限制".to_string()],
+        )
+        .expect("start non-delegated art runtime");
+        for (tool, input) in [
+            (
+                "command.output_read",
+                serde_json::json!({"actionId":"history-probe","startLine":1,"maxLines":5}),
+            ),
+            (
+                "canvas.asset_generate",
+                serde_json::json!({"prompt":"恢复视觉规范图","outputPath":AGENT_RUNTIME_ART_SPEC_PATH}),
+            ),
+            (
+                "file.write",
+                serde_json::json!({"path":"game/notes.txt","content":"scoped by other policies"}),
+            ),
+        ] {
+            assert!(
+                game_chat_delegated_art_agent_input_mutation_block(
+                    &root,
+                    "art-director",
+                    &run_id,
+                    tool,
+                    &input,
+                )
+                .is_none(),
+                "{source}/{tool} 不应被 game-chat 美术门拦截"
+            );
+        }
+    }
+}
+
 #[test]
 fn game_chat_dynamic_art_retry_guard_preserves_dag_art_and_non_art_delegated_retry() {
     let dag_temporary = tempfile::tempdir().expect("create full DAG art retry root");
diff --git a/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_tools/file_ops.rs b/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_tools/file_ops.rs
index e1469b246..90dcdce36 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_tools/file_ops.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_tools/file_ops.rs
@@ -146,6 +146,14 @@ fn game_chat_delegated_art_agent_mutation_scope_at(
         if game_chat_dynamic_art_retry_claims_game_chat_lineage_at(root, &task)? {
             return Ok(GameChatDelegatedArtAgentMutationScope::RetryLineageBlocked);
         }
+        // Live game-chat dynamic art children only ever run with the
+        // `agent-delegate` source (retry lineage is classified above).
+        // Scheduler-seeded DAG tasks and plain background runs must not reach
+        // the strict predicate: it fails closed on a missing run-profile
+        // binding and would block even their read-only tools.
+        if task.source != "agent-delegate" {
+            return Ok(GameChatDelegatedArtAgentMutationScope::Unrestricted);
+        }
     }
     // `assets/**` is a broad write scope. Grant it only after the same
     // canonical-output authorization used by Canvas replacement has verified