diff --git a/backend/apps/agents/manager/prompt/prompt_context.py b/backend/apps/agents/manager/prompt/prompt_context.py
index 73a0868d..9dadcde2 100644
--- a/backend/apps/agents/manager/prompt/prompt_context.py
+++ b/backend/apps/agents/manager/prompt/prompt_context.py
@@ -435,7 +435,12 @@ AGENT_IDENTITY = (
     f"when the task needs it (real explanation, code, steps), then stay clean and structured. "
     f"Don't open with \"Certainly\" or \"Great question\". Hard rule: never put a \"-\" dash in "
     f"your prose. No em dashes, no en dashes, no hyphen used as a dash. Use commas, periods, "
-    f"colons, or parentheses instead."
+    f"colons, or parentheses instead.\n\n"
+    f"# Dependencies and tooling\n"
+    f"Install what you need yourself (pip into a venv you make, npm install) and only mention it "
+    f"if it fails; never hand the user a raw install command to run. If git or another dev tool "
+    f"is missing, work without it in the plain directory; suggest installing it only when the "
+    f"task itself is about that tool, in one plain sentence with the reason."
 )
 
 
diff --git a/backend/apps/agents/manager/run/RunOptions.py b/backend/apps/agents/manager/run/RunOptions.py
index 3d17e79c..70cc28d3 100644
--- a/backend/apps/agents/manager/run/RunOptions.py
+++ b/backend/apps/agents/manager/run/RunOptions.py
@@ -205,6 +205,11 @@ class RunOptions(AgentManagerProtocol):
         )
         # The CLI's own auto-memory keys its directory on cwd, and every chat has its own workspace cwd, so it silently files memories into per-chat buckets no other chat reads; MemoryRead/MemoryWrite on the shared store is the one memory surface (ENG-222).
         options_kwargs.setdefault("env", {})["CLAUDE_CODE_DISABLE_AUTO_MEMORY"] = "1"
+        # Packaged builds put the app bundle's site-packages on PYTHONPATH, which shadows any venv an agent makes: pip reports success while installing nothing (ENG-347). Keep only the debugger injection dir.
+        p_pp = os.environ.get("PYTHONPATH", "")
+        if p_pp:
+            p_kept = [e for e in p_pp.split(os.pathsep) if e and "debugger" in os.path.basename(e.rstrip("/\\"))]
+            options_kwargs["env"]["PYTHONPATH"] = os.pathsep.join(p_kept)
         logger.info(f"[SPAWN-PHASE] provider-env done session={session_id[:8]} t={time.monotonic():.3f}")
         if mcp_servers:
             options_kwargs["mcp_servers"] = mcp_servers
diff --git a/backend/apps/outputs/app_builder_skill.md b/backend/apps/outputs/app_builder_skill.md
index 18d7d442..d721ccf9 100644
--- a/backend/apps/outputs/app_builder_skill.md
+++ b/backend/apps/outputs/app_builder_skill.md
@@ -272,6 +272,7 @@ and flips `BACKEND_PORT` in both `.env` and `.env.example`. Then run
 - Use Flask, Django, or any framework other than the FastAPI scaffold
   the script gives you.
 - Install your own venv or `pip install` manually.
+- Ask the user to run pip or install anything. Python deps go in `backend/pyproject.toml`; the framework's restart installs them. Users never run install commands.
 - Edit `backend/run.sh` or the SubApp framework.
 
 **Persist anything the user comes back to. Your process is disposable.**