Reduce LLM rewrite calls and add report intro conclusion

ai_daily_report/guide.py

@@ -23,8 +23,10 @@ def _clean_text(text: str, limit: int | None = None) -> str:
 def _build_prompt(items: list[NewsItem]) -> str:
     payload = {
         "task": (
-            "Generate a concise AI daily report guide. Return JSON only. Do not use 强信号/中信号/待验证. "
-            "Use a short theme and 2-4 daily threads. Every thread must reference existing item_ids."
+            "Generate a concise Chinese AI daily report guide. Return JSON only. "
+            "Do not use 强信号/中信号/待验证. Do not add facts. "
+            "Write one opening intro, a short theme, 2-4 daily threads, and one closing conclusion. "
+            "Every thread must reference existing item_ids."
         ),
         "items": [
             {
@@ -37,6 +39,7 @@ def _build_prompt(items: list[NewsItem]) -> str:
             for item in items
         ],
         "output_schema": {
+            "intro": "one opening paragraph under 160 Chinese characters",
             "theme": "one sentence under 120 Chinese characters",
             "threads": [
                 {
@@ -46,23 +49,27 @@ def _build_prompt(items: list[NewsItem]) -> str:
                     "kind": "thread|uncertain",
                 }
             ],
+            "conclusion": "one closing paragraph under 180 Chinese characters",
         },
     }
     return json.dumps(payload, ensure_ascii=False)
 
 
+def _empty_guide() -> dict[str, Any]:
+    return {"intro": "", "theme": "", "threads": [], "conclusion": ""}
+
+
 def generate_guide(
     items: list[NewsItem],
     *,
     llm_call: GuideLlmCall,
 ) -> tuple[dict[str, Any], dict[str, Any]]:
     if not items:
-        return {
-            "theme": "",
-            "threads": [],
-        }, {
+        return _empty_guide(), {
             "input_count": 0,
+            "intro_present": False,
             "theme_present": False,
+            "conclusion_present": False,
             "thread_count": 0,
             "dropped_thread_count": 0,
             "fallback_used": False,
@@ -72,12 +79,11 @@ def generate_guide(
     try:
         obj = parse_json_object(llm_call(_build_prompt(items)))
     except Exception as exc:
-        return {
-            "theme": "",
-            "threads": [],
-        }, {
+        return _empty_guide(), {
             "input_count": len(items),
+            "intro_present": False,
             "theme_present": False,
+            "conclusion_present": False,
             "thread_count": 0,
             "dropped_thread_count": 0,
             "fallback_used": True,
@@ -100,11 +106,15 @@ def generate_guide(
         kind = thread.get("kind") if thread.get("kind") in ("thread", "uncertain") else "thread"
         threads.append({"title": title, "text": text, "item_ids": item_ids, "kind": kind})
 
+    intro = _clean_text(str(obj.get("intro") or ""), limit=160)
     theme = _clean_text(str(obj.get("theme") or ""), limit=120)
-    guide = {"theme": theme, "threads": threads}
+    conclusion = _clean_text(str(obj.get("conclusion") or ""), limit=180)
+    guide = {"intro": intro, "theme": theme, "threads": threads, "conclusion": conclusion}
     report = {
         "input_count": len(items),
+        "intro_present": bool(intro),
         "theme_present": bool(theme),
+        "conclusion_present": bool(conclusion),
         "thread_count": len(threads),
         "dropped_thread_count": dropped,
         "fallback_used": False,