fix: prevent master agent asking for clarification when receipts are uploaded

When a zip/image arrives via /upload, the LLM was classifying the
message as needs_clarification=True (because the chat body was just a
filename like "download (8).zip", not an instruction), and the early
return on line 91 fired before the receipts safety guard on line 106,
so the guard never executed.

master_agent: move the receipts safety guard to BEFORE the
needs_clarification early-return.  If extra_context contains receipts,
unconditionally set needs_clarification=False and ensure expenses_agent
is in the agents list — the LLM cannot veto an upload with a question.

upload router: normalize empty or filename-only messages (e.g. when the
user drops a file in Discuss chat with no text) to
"Create an expense report from these uploaded receipts." so the LLM
intent classification also has a sensible string to work with.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

agent_service/agents/master_agent.py

@@ -88,6 +88,17 @@ class MasterAgent:
             await self._memory.append_message(user_id, 'user', message, directive_id)
             context = await self._build_context(user_id, message)
             intent = await self._classify_intent(context, message)
+
+            # Safety guard: when receipts arrive via the upload flow, always
+            # route to expenses_agent — regardless of what the LLM decided.
+            # MUST run BEFORE the needs_clarification early-return; otherwise an
+            # LLM that asks "please provide more context" blocks a valid upload.
+            if (extra_context or {}).get('receipts'):
+                intent.needs_clarification = False
+                intent.clarification_question = None
+                if 'expenses_agent' not in intent.agents:
+                    intent.agents.append('expenses_agent')
+
             if intent.needs_clarification:
                 q = intent.clarification_question or 'Could you provide more details?'
                 await self._memory.append_message(user_id, 'assistant', q, directive_id)
@@ -101,11 +112,6 @@ class MasterAgent:
                 await self._log_directive_complete(directive_id, 'complete', response_text)
                 return MasterResponse(directive_id=directive_id, response=response_text,
                                       status='complete')
-            # When receipts are present (upload flow), always dispatch expenses_agent
-            # even if the user's message is a one-word reply like "skip duplicates".
-            if (extra_context or {}).get('receipts') and 'expenses_agent' not in intent.agents:
-                intent.agents.append('expenses_agent')
-                intent.needs_clarification = False
             access = await self._check_access(user_id, intent.agents)
             if not access.allowed:
                 denied = ', '.join(access.denied_agents)

agent_service/routers/upload.py

@@ -1,9 +1,14 @@
 from __future__ import annotations
 import asyncio
 import logging
+import re
 import uuid
 from typing import List, Optional
 
+# Matches messages that are just a filename (e.g. "download (8).zip", "receipt.jpg").
+# When the chat body is only the filename, the LLM has nothing useful to classify.
+_FILENAME_ONLY_RE = re.compile(r'^[\w\s\-.()\[\]]+\.\w{2,6}$')
+
 from fastapi import APIRouter, File, Form, HTTPException, Request, UploadFile, status
 
 from ..config import get_settings
@@ -35,6 +40,14 @@ async def upload(
     from concurrent.futures import ThreadPoolExecutor
     _ocr_executor = ThreadPoolExecutor(max_workers=2)
 
+    # Normalise message: if the user sent no text (or the chat body is just the
+    # filename Odoo auto-inserts), give the master agent a clear instruction so
+    # it routes to expenses_agent rather than asking for clarification.
+    stripped = (message or '').strip()
+    if not stripped or _FILENAME_ONLY_RE.match(stripped):
+        message = 'Create an expense report from these uploaded receipts.'
+        logger.debug('upload: normalised empty/filename message for user_id=%s', user_id)
+
     receipts: list[dict] = []
     loop = asyncio.get_event_loop()
     for f in files: