segregated response keys

app.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 from fastapi import FastAPI, HTTPException
 from fastapi.responses import RedirectResponse
 from pydantic import BaseModel, Field
+import re
 
 from rag.chain import aanswer
 from rag.retriever import get_retriever
@@ -24,6 +25,7 @@ class ChatRequest(BaseModel):
 class ChatResponse(BaseModel):
     question: str
     answer: str
+    sources: list[str] = Field(default_factory=list)
 
 
 @app.get("/health")
@@ -44,4 +46,15 @@ async def chat(payload: ChatRequest) -> ChatResponse:
     except Exception as error:
         raise HTTPException(status_code=500, detail=str(error))
 
-    return ChatResponse(question=payload.question, answer=answer)
+    # Extract trailing "Sources:" block if present and return as separate list
+    m = re.search(r"(?i)\bSources\s*:?\s*(.*)$", answer, flags=re.DOTALL)
+    sources: list[str] = []
+    if m:
+        sources_text = m.group(1).strip()
+        # Remove the Sources block from the answer text
+        answer = answer[: m.start()].strip()
+        # Split on commas and newlines, strip whitespace, ignore empties
+        parts = re.split(r"[,\n;]+", sources_text)
+        sources = [p.strip() for p in parts if p.strip()]
+
+    return ChatResponse(question=payload.question, answer=answer, sources=sources)