diff --git a/apps/api/src/stt.ts b/apps/api/src/stt.ts
index fa20819..5a38365 100644
--- a/apps/api/src/stt.ts
+++ b/apps/api/src/stt.ts
@@ -12,7 +12,13 @@ router.post('/', async (req, res) => {
       return res.status(400).json({ error: 'bucket (or env S3_BUCKET) and key are required' });
     }
     if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+      console.error('STT failed: missing OPENAI_API_KEY');
+      return res.status(500).json({ error: 'Transcription not configured' });
+    }
+    const { S3_ENDPOINT, S3_ACCESS_KEY, S3_SECRET_KEY } = process.env;
+    if (!S3_ENDPOINT || !S3_ACCESS_KEY || !S3_SECRET_KEY) {
+      console.error('STT failed: missing S3 config (S3_ENDPOINT/S3_ACCESS_KEY/S3_SECRET_KEY)');
+      return res.status(500).json({ error: 'Object storage not configured' });
     }
 
     const { buffer, contentType } = await downloadObject({ bucket, key });
diff --git a/tmp/sample.webm b/tmp/sample.webm
new file mode 100644
index 0000000..cb43b5c
Binary files /dev/null and b/tmp/sample.webm differ