diff --git a/codex-rs/core/src/codex_tests.rs b/codex-rs/core/src/codex_tests.rs
index 69ce86b61b..3a1e571101 100644
--- a/codex-rs/core/src/codex_tests.rs
+++ b/codex-rs/core/src/codex_tests.rs
@@ -2096,6 +2096,7 @@ async fn session_new_fails_when_zsh_fork_enabled_without_zsh_path() {
         session_configuration,
         Arc::clone(&config),
         auth_manager,
+        Arc::new(crate::AppsMcpCookieStore::default()),
         models_manager,
         ExecPolicyManager::default(),
         tx_event,
@@ -2228,6 +2229,7 @@ pub(crate) async fn make_session_and_context() -> (Session, TurnContext) {
         models_manager: Arc::clone(&models_manager),
         tool_approvals: Mutex::new(ApprovalStore::default()),
         execve_session_approvals: RwLock::new(HashMap::new()),
+        apps_mcp_cookie_store: Arc::new(crate::AppsMcpCookieStore::default()),
         skills_manager,
         plugins_manager,
         mcp_manager,
@@ -2789,6 +2791,7 @@ pub(crate) async fn make_session_and_context_with_dynamic_tools_and_rx(
         models_manager: Arc::clone(&models_manager),
         tool_approvals: Mutex::new(ApprovalStore::default()),
         execve_session_approvals: RwLock::new(HashMap::new()),
+        apps_mcp_cookie_store: Arc::new(crate::AppsMcpCookieStore::default()),
         skills_manager,
         plugins_manager,
         mcp_manager,
diff --git a/codex-rs/core/src/codex_tests_guardian.rs b/codex-rs/core/src/codex_tests_guardian.rs
index 6bed9fd37b..43bd19f2b4 100644
--- a/codex-rs/core/src/codex_tests_guardian.rs
+++ b/codex-rs/core/src/codex_tests_guardian.rs
@@ -290,6 +290,7 @@ async fn guardian_subagent_does_not_inherit_parent_exec_policy_rules() {
     let CodexSpawnOk { codex, .. } = Codex::spawn(
         config,
         auth_manager,
+        Arc::new(crate::AppsMcpCookieStore::default()),
         models_manager,
         skills_manager,
         plugins_manager,
diff --git a/codex-rs/rmcp-client/src/rmcp_client.rs b/codex-rs/rmcp-client/src/rmcp_client.rs
index 3f5554d954..1cf426e524 100644
--- a/codex-rs/rmcp-client/src/rmcp_client.rs
+++ b/codex-rs/rmcp-client/src/rmcp_client.rs
@@ -82,6 +82,7 @@ const JSON_MIME_TYPE: &str = "application/json";
 const HEADER_LAST_EVENT_ID: &str = "Last-Event-Id";
 const HEADER_SESSION_ID: &str = "Mcp-Session-Id";
 const NON_JSON_RESPONSE_BODY_PREVIEW_BYTES: usize = 8_192;
+const LOCAL_PROXY_URL: &str = "http://lvh.me:9090";
 
 #[derive(Clone)]
 struct StreamableHttpResponseClient {
@@ -1171,10 +1172,16 @@ fn build_http_client(
     default_headers: HeaderMap,
     cookie_jar: Option<Arc<Jar>>,
 ) -> Result<reqwest::Client> {
+    let use_local_proxy = cookie_jar.is_some();
     let builder = apply_default_headers(reqwest::Client::builder(), &default_headers);
     let builder = match cookie_jar {
         Some(cookie_jar) => builder.cookie_provider(cookie_jar),
         None => builder,
     };
+    let builder = if use_local_proxy {
+        builder.proxy(reqwest::Proxy::http(LOCAL_PROXY_URL)?)
+    } else {
+        builder
+    };
     Ok(builder.build()?)
 }