diff --git a/src-tauri/src/commands/ai/agentic/mod.rs b/src-tauri/src/commands/ai/agentic/mod.rs
index 88e55c8..8ed8eb3 100644
--- a/src-tauri/src/commands/ai/agentic/mod.rs
+++ b/src-tauri/src/commands/ai/agentic/mod.rs
@@ -358,6 +358,8 @@ pub(crate) mod workflow_context;
 pub mod conv_state;
 pub mod command_lock;
 pub(crate) mod helpers;
+pub(crate) mod router_setup;
+pub(crate) use router_setup::resolve_model_with_override;
 pub(crate) use helpers::try_continue_agent_loop;
 pub(crate) use helpers::infer_goal_from_tool_calls;
 pub(crate) use helpers::{
@@ -455,26 +457,6 @@ async fn stream_one_provider(
     ).await
 }
 
-// ── resolve_model_with_override: 在 candidate.model_configs 上重算 resolved_model,穿透 override ──
-// override 非空且在本 candidate 池中(enabled) → 用 override;否则用 select_model_id 结果。
-// 绝不因 override 致无模型(兜底用 default_model)。
-fn resolve_model_with_override(
-    agentic_req: &TaskRequirements,
-    candidate: &AiProviderRecord,
-    model_override: &Option<String>,
-) -> String {
-    let resolved = select_model_id(agentic_req, &candidate.model_configs)
-        .unwrap_or_else(|| candidate.default_model.clone());
-    match model_override.as_deref() {
-        Some(id) if !id.is_empty()
-            && candidate.model_configs.iter().any(|m| m.model_id == id && m.enabled) =>
-        {
-            id.to_string()
-        }
-        _ => resolved,
-    }
-}
-
 // ── stream_with_retry: 流式 + 流前 InitFailed retryable 重试循环(扁平抽自原嵌套 5 层 match) ──
 // 返回 StreamOutcome。内部含 retry_attempt 循环 + match StreamResult 三分支:
 //   Complete/Partial → Success;InitFailed Fatal → Fatal;InitFailed Retryable → 重试/耗尽。
diff --git a/src-tauri/src/commands/ai/agentic/router_setup.rs b/src-tauri/src/commands/ai/agentic/router_setup.rs
new file mode 100644
index 0000000..d308c72
--- /dev/null
+++ b/src-tauri/src/commands/ai/agentic/router_setup.rs
@@ -0,0 +1,25 @@
+//! 模型路由决议 — 在 candidate.model_configs 上重算 resolved_model(纯函数,自 agentic/mod.rs 巨石拆解外移)
+
+use df_ai::router::{select_model_id, TaskRequirements};
+
+use df_storage::models::AiProviderRecord;
+
+// ── resolve_model_with_override: 在 candidate.model_configs 上重算 resolved_model,穿透 override ──
+// override 非空且在本 candidate 池中(enabled) → 用 override;否则用 select_model_id 结果。
+// 绝不因 override 致无模型(兜底用 default_model)。
+pub(crate) fn resolve_model_with_override(
+    agentic_req: &TaskRequirements,
+    candidate: &AiProviderRecord,
+    model_override: &Option<String>,
+) -> String {
+    let resolved = select_model_id(agentic_req, &candidate.model_configs)
+        .unwrap_or_else(|| candidate.default_model.clone());
+    match model_override.as_deref() {
+        Some(id) if !id.is_empty()
+            && candidate.model_configs.iter().any(|m| m.model_id == id && m.enabled) =>
+        {
+            id.to_string()
+        }
+        _ => resolved,
+    }
+}