diff --git a/navi/core/context_builder.py b/navi/core/context_builder.py
index 5253000..4494e36 100644
--- a/navi/core/context_builder.py
+++ b/navi/core/context_builder.py
@@ -128,10 +128,16 @@
         extra_system: list[Message] | None = None,
         session_id: str | None = None,
     ) -> list[Message]:
-        system_msg = Message(
-            role="system",
-            content=self.build_system_prompt(profile),
-        )
+        system_prompt = self.build_system_prompt(profile)
+        if session_id:
+            system_prompt += (
+                f"\n\n---\n\n"
+                f"[Session context]\n"
+                f"Session ID: {session_id}\n"
+                f"Session files directory: {_config.settings.session_files_dir}/{session_id}/\n"
+                f"When writing files the user should see, always use the session directory path above."
+            )
+        system_msg = Message(role="system", content=system_prompt)
         conv = [m for m in session_context if m.role != "system"]
         result: list[Message] = [system_msg]
         if mem:
@@ -156,16 +162,4 @@
                 content=f"[Iteration {iteration + 1}/{max_iterations} — {remaining} remaining.{urgency}]",
             ))
 
-        # Inject session identity so the model knows its own session_id for file paths
-        if session_id:
-            result.insert(1, Message(
-                role="system",
-                content=(
-                    f"[Session context]\n"
-                    f"Session ID: {session_id}\n"
-                    f"Session files directory: {_config.settings.session_files_dir}/{session_id}/\n"
-                    f"When writing files the user should see, always use the session directory path above."
-                ),
-            ))
-
         return result
diff --git a/navi/main.py b/navi/main.py
index 091571d..8921aa7 100644
--- a/navi/main.py
+++ b/navi/main.py
@@ -7,6 +7,7 @@
 
 import structlog
 from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
 from fastapi.responses import FileResponse
 from fastapi.staticfiles import StaticFiles
 
@@ -27,6 +28,14 @@
     version="0.1.0",
 )
 
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=False,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
 # Keep reference to background cleanup task so unhandled exceptions are not lost
 _cleanup_task = None
 
diff --git a/navi/profiles/modeler_3d/system_prompt.txt b/navi/profiles/modeler_3d/system_prompt.txt
index 4fe47a4..4b960bc 100644
--- a/navi/profiles/modeler_3d/system_prompt.txt
+++ b/navi/profiles/modeler_3d/system_prompt.txt
@@ -7,8 +7,8 @@
 1. **`filesystem write`** — write the OpenSCAD script (`.scad`) to the session directory.
 2. **`model_3d`** — compile the `.scad` into a binary `.stl`.
 3. **`content_publish`** — show the user the STL in an interactive 3D viewer.
-4. **`render_3d`** — generate PNG previews from different angles so both you and the user can inspect the model.
-5. **`content_publish`** again — publish each PNG so the user sees the renders.
+4. **`render_3d`** — generate PNG previews from different angles for your own inspection.
+5. **`image_view`** — inspect each PNG so YOU can verify geometry. Do NOT publish PNGs to the user.
 
 ## Workflow
 
@@ -17,8 +17,8 @@
 3. **Write OpenSCAD** — use `filesystem write` to save the `.scad` script to the session directory.
 4. **Compile STL** — call `model_3d(scad_path=..., output_path=...)`.
 5. **Publish STL** — call `content_publish(filename="...stl")` so the user sees the 3D viewer.
-6. **Render previews** — call `render_3d(source="...stl", views=["iso","front","top"])` to generate PNGs.
-7. **Publish previews** — call `content_publish` on each PNG (e.g., `bracket.iso.png`).
+6. **Render previews** — call `render_3d(source="...stl", views=["iso","front","top"])` to generate PNGs for your own inspection.
+7. **Inspect previews** — call `image_view` on each PNG to verify geometry. Do NOT publish PNGs to the user.
 8. **Validate** — if you need programmatic checks (watertight, manifold, dimensions), use `code_exec` with `trimesh` on the STL.
 
 ## OpenSCAD is your primary engine
diff --git a/persona.txt b/persona.txt
index 275f66d..a201bcb 100644
--- a/persona.txt
+++ b/persona.txt
@@ -30,7 +30,7 @@
 1. Persistent workspace: `workspace/` (relative to the project root).
 Use it for long-term private working files: scripts, notes, datasets, configs, research results, intermediate code, and artifacts that should survive beyond one chat session. Do NOT write working files to the project root.
 
-2. Session files directory: `session_files/{session_id}/` by default; the exact root is configured by `SESSION_FILES_DIR`.
+2. Session files directory: a per-session directory whose exact path is injected into every turn context.
 This is the per-session file area used for user uploads and files the user should view or download in the chat.
 
 Decision rule: