Replace max_turns cap with 90% confidence stopping criterion in agent setup

- Remove fixed _MAX_TURNS=5 instruction from system prompt; LLM now decides
  when to stop based on self-assessed confidence (>= 90%)
- Add _MIN_TURNS_BEFORE_NUDGE=3 and raise safety cap to _MAX_TURNS=15
- Nudge message and hard cap still act as a safety net for infinite loops

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

app/api/routes/agent_setup.py

@@ -43,8 +43,10 @@ _SESSION_TTL_SECONDS: int = 1800  # 30 minutes
 _TEMPLATE_START = "PROMPT_TEMPLATE_START"
 _TEMPLATE_END = "PROMPT_TEMPLATE_END"
 
-# Maximum number of conversation turns before the LLM is nudged to wrap up.
+# Minimum turns before we consider nudging the LLM to wrap up.
-_MAX_TURNS: int = 5
+_MIN_TURNS_BEFORE_NUDGE: int = 3
+# Hard cap to avoid infinite loops (safety net, not the primary stopping criterion).
+_MAX_TURNS: int = 15
 # Max tool-calling steps per LLM invocation.
 _MAX_TOOL_STEPS: int = 6
 
@@ -128,8 +130,10 @@ and must perform CRUD operations using tools to create records.  It should speci
   - Concrete examples of mappings based on what you discovered in the directory.
 
 {existing_section}\
-Do not ask more than {max_turns} questions total.  Begin by exploring the directory,
+Keep asking clarifying questions until you are at least 90% confident you have
-then ask your first question.\
+enough information to generate an accurate prompt_template.  Once you reach that
+confidence level, stop asking and produce the final template immediately.
+Begin by exploring the directory, then ask your first question.\
 """
 
 
@@ -150,7 +154,6 @@ def _build_system_prompt(
         template_start=_TEMPLATE_START,
         template_end=_TEMPLATE_END,
         existing_section=existing_section,
-        max_turns=_MAX_TURNS,
     )
 
 
@@ -356,8 +359,8 @@ async def handle_journey_message(
     prompt_template = _extract_template(ai_reply)
     done = prompt_template is not None
 
-    # If the LLM didn't produce a template but we've hit max turns, nudge it
+    # If the LLM didn't produce a template, nudge it once it has asked enough
-    # and call the LLM one more time to force template generation.
+    # questions (>= _MIN_TURNS_BEFORE_NUDGE) or hits the hard safety cap.
     if not done:
         turns = sum(1 for t in session.history if t["role"] == "user")
         if turns >= _MAX_TURNS: