diff --git a/.jules/sentinel.md b/.jules/sentinel.md
index c1caaeb..31ec4e6 100644
--- a/.jules/sentinel.md
+++ b/.jules/sentinel.md
@@ -6,3 +6,8 @@
 **Vulnerability:** The custom `SafeStaticFiles` middleware in `src/audioformation/server/app.py` intended to block access to sensitive directories (like `00_CONFIG` and `.git`). However, it used `p = Path(path).lower()`, which raises an `AttributeError` because `pathlib.Path` objects lack a `.lower()` method. This effectively broke static file serving entirely (causing 500 errors) and represented a malformed security check. If such errors were ever 'swallowed' without raising an HTTP exception, it could result in 'failing open' and allowing access to sensitive files.
 **Learning:** Security checks that rely on path manipulation or normalization must be carefully tested for runtime exceptions. An unhandled exception in a security gate can either block legitimate traffic (Denial of Service) or, if caught improperly elsewhere, fail open. Always normalize the string representation of paths before converting them to `Path` objects.
 **Prevention:** Thoroughly test security middleware endpoints for both valid and invalid access attempts. Ensure that path string normalizations like `.lower()` are applied directly to the string before instantiating `Path(str(path).lower())`.
+
+## 2025-05-25 - Prevent Exception String Leakage in API Routes
+**Vulnerability:** The raw string representation of caught internal exceptions (`Exception as e`) was being exposed directly to clients inside HTTP 500 responses (e.g., `raise HTTPException(status_code=500, detail=f"Upload failed: {e}")`).
+**Learning:** This exposes sensitive internal application state, stack details, or potentially infrastructure specifics (like file paths or database queries) to external users, enabling reconnaissance for further attacks.
+**Prevention:** Always log the exception details internally using `logger.error` or `logger.exception` and return a generic, static message to the client (e.g., `"Upload failed"` or `"Internal server error"`).
diff --git a/src/audioformation/server/routes.py b/src/audioformation/server/routes.py
index 34c9bec..d216eb6 100644
--- a/src/audioformation/server/routes.py
+++ b/src/audioformation/server/routes.py
@@ -185,7 +185,8 @@ async def ingest_files(
                 shutil.copyfileobj(file.file, buffer)
     except Exception as e:
         shutil.rmtree(tmp_dir, ignore_errors=True)
-        raise HTTPException(status_code=500, detail=f"Upload failed: {e}")
+        logger.error(f"Upload failed for project {project_id}: {e}")
+        raise HTTPException(status_code=500, detail="Upload failed")
 
     background_tasks.add_task(
         _run_with_status,
diff --git a/uv.lock b/uv.lock
index e34eac4..7970295 100644
--- a/uv.lock
+++ b/uv.lock
@@ -270,7 +270,7 @@ requires-dist = [
     { name = "jsonschema", specifier = ">=4.21,<5" },
     { name = "midiutil", marker = "extra == 'midi'", specifier = ">=1.2,<2" },
     { name = "mutagen", marker = "extra == 'm4b'", specifier = ">=1.47,<2" },
-    { name = "mypy", marker = "extra == 'dev'", specifier = ">=1.0,<2" },
+    { name = "mypy", marker = "extra == 'dev'", specifier = ">=1.0,<3" },
     { name = "numpy", specifier = ">=1.26,<3" },
     { name = "pre-commit", marker = "extra == 'dev'", specifier = ">=3.6,<5" },
     { name = "pydub", specifier = ">=0.25,<1" },
@@ -280,7 +280,7 @@ requires-dist = [
     { name = "pytest-cov", marker = "extra == 'dev'", specifier = ">=4.0,<8" },
     { name = "python-dotenv", marker = "extra == 'cloud'", specifier = ">=1.0,<2" },
     { name = "python-multipart", marker = "extra == 'server'", specifier = ">=0.0.27,<1" },
-    { name = "ruff", marker = "extra == 'dev'", specifier = ">=0.1.9" },
+    { name = "ruff", marker = "extra == 'dev'", specifier = ">=0.15.1" },
     { name = "silero-vad", marker = "extra == 'vad'", specifier = ">=6.0,<7" },
     { name = "soundfile", specifier = ">=0.12,<1" },
     { name = "transformers", specifier = ">=4.44,<6" },