Fix: improve system prompt to not false-negative when answer is in context

agent.py

@@ -30,8 +30,9 @@ MAX_RETRIES = 2
 
 SYSTEM_PROMPT = """You are ClinIQ, a clinical document assistant for small medical clinics.
 Answer ONLY from the provided document excerpts. Cite the source document for every claim.
-If information is not in the excerpts, say clearly: "Not found in the provided documents."
-Be concise and medically precise. Never guess or hallucinate clinical information."""
+If information is explicitly stated in the excerpts, answer from it — do not say "not found" when the answer IS present.
+Only say "Not found in the provided documents" if the information is genuinely absent from ALL excerpts.
+Be concise and medically precise. Never hallucinate clinical information."""
 
 STRUCTURED_SCHEMAS = {
     "medications":  ("List every medication with dose and frequency as JSON array: "