Soften the tone of the docs and comments written today

apps/ai-service/rag/agent.py

@@ -259,12 +259,27 @@ class RagAgent:
             if frame.population in {"tre_em", "tre_so_sinh"} and (
                 frame.age_text is None or frame.weight_kg is None
             ):
+                # Both fields stay required. The formulary branches pediatric
+                # dosing on BOTH — paracetamol prints an age band ("Trẻ em
+                # 4-6 tuổi: 240 mg") *and* a weight rule ("10-50 kg: 15
+                # mg/kg") — so answering with only one of them would mean
+                # picking a regimen the source does not let us pick.
+                #
+                # What changed on 2026-08-11 is the *question*, not the gate.
+                # The fallback used to ask for age and weight every time,
+                # including for whichever field the user had already given
+                # (reproduced 5/5 live: "Bé 18 ký ...", "Bé nặng 18 kg ...",
+                # "Trẻ 5 tuổi ..." all received the same sentence). The
+                # effect was most visible when understanding.py did well: a
+                # frame that parsed the weight and set needs_clarify=false
+                # reaches this fallback, so a clearer question from the user
+                # produced a more redundant question back.
                 return AgentReply(
                     "clarify", "missing_pediatric_age_or_weight",
                     clarification=(
                         frame.clarify_reason
                         if frame.needs_clarify and frame.clarify_reason
-                        else "Bé bao nhiêu tuổi và cân nặng bao nhiêu kg?"
+                        else _pediatric_clarify_question(frame)
                     ),
                     drugs=frame.drugs, turn_type=tt,
                     quick_replies=(
@@ -498,6 +513,32 @@ def _display_name(drug_id: str) -> str:
     return drug_id.replace("_", " ").title()
 
 
+def _pediatric_clarify_question(frame: QueryFrame) -> str:
+    """Ask for the pediatric field that is actually missing.
+
+    The caller still requires both age and weight; this only stops the
+    question from asking for something the user already supplied in the very
+    same sentence, which reads as not having been listened to and invites
+    them to repeat themselves into the clarify-loop breaker.
+
+    When a field IS known it is echoed back, so the user can see the value
+    was received and correct it if the parse was wrong (e.g. a colloquial
+    "18 ký" read as 18 kg).
+    """
+    has_age = frame.age_text is not None
+    has_weight = frame.weight_kg is not None
+    if has_age and not has_weight:
+        return f"Bé {frame.age_text} nặng bao nhiêu kg?"
+    if has_weight and not has_age:
+        return f"Bé nặng {_format_kg(frame.weight_kg)} kg, vậy bé bao nhiêu tuổi?"
+    return "Bé bao nhiêu tuổi và cân nặng bao nhiêu kg?"
+
+
+def _format_kg(weight_kg: float) -> str:
+    """Render a weight without a trailing '.0' on whole kilograms."""
+    return f"{weight_kg:g}"
+
+
 def _is_section_overview(turn: str, frame: QueryFrame) -> bool:
     """Separate a handbook survey from a patient-specific decision.