fixing agent chat window

backend/apps/agents/agents.py

@@ -144,10 +144,10 @@ async def get_session(session_id: str) -> dict:
 
 @agents.router.post("/launch_agent")
 async def launch_agent(
-    model: str = Body(),
-    mode: str = Body(),
-    system_prompt: str = Body(),
-    max_turns: int = Body(),
+    model: str = Body(default="sonnet"),
+    mode: str = Body(default="agent"),
+    system_prompt: str = Body(default=""),
+    max_turns: int = Body(default=100),
     dashboard_id: Optional[str] = Body(default=None),
 ) -> dict:
     agent: Agent = Agent(

backend/apps/settings/AppSettings.py

@@ -9,6 +9,7 @@ class AppSettings(BaseModel):
     default_model: str = "sonnet"
     default_mode: str = "agent"
     default_max_turns: Optional[int] = None
+    default_thinking_level: str = "auto"
     anthropic_api_key: Optional[str] = None
 
     # Dashboard / UI preferences

backend/core/shared_structs/agent/AgentSnapshot.py

@@ -1,11 +1,11 @@
 from pydantic import BaseModel, Field
-from typing import Optional, List
+from typing import Any, Optional, List
 from backend.core.shared_structs.agent.MessageLog import MessageLog
 from backend.core.shared_structs.agent.ApprovalRequest import ApprovalRequest
 
 class AgentSnapshot(BaseModel):
     """Wire-format representation of an Agent — no runtime fields (task, lock, on_event)."""
-    session_id: str
+    session_id: str = Field(..., serialization_alias="id")
     model: str
     mode: str
     status: str
@@ -15,4 +15,8 @@ class AgentSnapshot(BaseModel):
     messages: MessageLog = Field(default_factory=MessageLog)
     pending_approvals: List[ApprovalRequest] = Field(default_factory=list)
     sub_agents: list = Field(default_factory=list)
-    sub_branches: list = Field(default_factory=list)
+    sub_branches: list = Field(default_factory=list)
+
+    def model_dump(self, **kwargs: Any) -> dict[str, Any]:
+        kwargs.setdefault("by_alias", True)
+        return super().model_dump(**kwargs)

frontend/src/app/pages/Settings/Settings.tsx

@@ -1151,6 +1151,21 @@ const Settings: React.FC = () => {
   const [activeTab, setActiveTab] = useState<'general' | 'models' | 'usage' | 'commands'>('general');
   const [form, setForm] = useState<AppSettings>({ ...settings });
 
+  const effectiveDefaultModel = useMemo(() => {
+    if (modelOptions.flat.some((m) => m.value === form.default_model)) {
+      return form.default_model;
+    }
+    return modelOptions.flat[0]?.value ?? form.default_model;
+  }, [modelOptions.flat, form.default_model]);
+
+  // Sync form.default_model to effectiveDefaultModel when the saved model
+  // is no longer available (e.g., subscription disconnected, models changed).
+  useEffect(() => {
+    if (effectiveDefaultModel !== form.default_model) {
+      setForm((prev) => ({ ...prev, default_model: effectiveDefaultModel }));
+    }
+  }, [effectiveDefaultModel, form.default_model]);
+
   // When the modal opens with a requested tab (e.g., from the warning
   // banner's "Configure models" link), switch to it.
   useEffect(() => {
@@ -1469,7 +1484,7 @@ const Settings: React.FC = () => {
           </Box>
           <FormControl size="small" sx={{ minWidth: 220 }}>
             <Select
-              value={form.default_model}
+              value={effectiveDefaultModel}
               onChange={(e) => setForm({ ...form, default_model: e.target.value })}
               sx={{ fontSize: '0.85rem' }}
               MenuProps={{ PaperProps: { sx: { bgcolor: c.bg.surface, color: c.text.primary } } }}

frontend/src/shared/state/toolsSlice.ts

@@ -158,7 +158,7 @@ export const discoverTools = createAsyncThunk(
 );
 
 export const fetchBuiltinPermissions = createAsyncThunk('tools/fetchBuiltinPermissions', async () => {
-  const res = await fetch(`${TOOLS_API}/builtin/permissions`);
+  const res = await fetch(`${TOOLS_API}/get_builtin_permissions`);
   const data = await res.json();
   return data.permissions as Record<string, string>;
 });
@@ -166,7 +166,7 @@ export const fetchBuiltinPermissions = createAsyncThunk('tools/fetchBuiltinPermi
 export const updateBuiltinPermissions = createAsyncThunk(
   'tools/updateBuiltinPermissions',
   async (permissions: Record<string, string>) => {
-    const res = await fetch(`${TOOLS_API}/builtin/permissions`, {
+    const res = await fetch(`${TOOLS_API}/update_builtin_permissions`, {
       method: 'PUT',
       headers: { 'Content-Type': 'application/json' },
       body: JSON.stringify({ permissions }),