From f2d051eea5b636efbd6bb23dcad3b0ea3f16bf53 Mon Sep 17 00:00:00 2001
From: yangdx <gzdaniel@me.com>
Date: Sun, 27 Jul 2025 21:10:47 +0800
Subject: [PATCH] Fix: Improve keyword extraction prompt for robust JSON
 output.

*   Emphasize strict JSON output in key extration prompt
*   Clean up prompt examples in key extration prompt
*   Log raw LLM response on JSON error
---
 lightrag/operate.py |  1 +
 lightrag/prompt.py  | 21 ++++++++++++---------
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/lightrag/operate.py b/lightrag/operate.py
index e976a5b4..108a8690 100644
--- a/lightrag/operate.py
+++ b/lightrag/operate.py
@@ -1852,6 +1852,7 @@ async def extract_keywords_only(
         keywords_data = json.loads(match.group(0))
     except json.JSONDecodeError as e:
         logger.error(f"JSON parsing error: {e}")
+        logger.error(f"LLM respond: {result}")
         return [], []
 
     hl_keywords = keywords_data.get("high_level_keywords", [])
diff --git a/lightrag/prompt.py b/lightrag/prompt.py
index f0d48a13..570ea7b8 100644
--- a/lightrag/prompt.py
+++ b/lightrag/prompt.py
@@ -251,7 +251,7 @@ Given the query and conversation history, list both high-level and low-level key
 ######################
 {examples}
 
-#############################
+######################
 ---Real Data---
 ######################
 Conversation History:
@@ -259,42 +259,45 @@ Conversation History:
 
 Current Query: {query}
 ######################
-The `Output` should be human text, not unicode characters. Keep the same language as `Query`.
-Output:
+The `Output` should be in JSON format, with no other text before and after the JSON. Use the same language as `Current Query`.
 
+Output:
 """
 
 PROMPTS["keywords_extraction_examples"] = [
     """Example 1:
 
 Query: "How does international trade influence global economic stability?"
-################
+
 Output:
 {
   "high_level_keywords": ["International trade", "Global economic stability", "Economic impact"],
   "low_level_keywords": ["Trade agreements", "Tariffs", "Currency exchange", "Imports", "Exports"]
 }
-#############################""",
+
+""",
     """Example 2:
 
 Query: "What are the environmental consequences of deforestation on biodiversity?"
-################
+
 Output:
 {
   "high_level_keywords": ["Environmental consequences", "Deforestation", "Biodiversity loss"],
   "low_level_keywords": ["Species extinction", "Habitat destruction", "Carbon emissions", "Rainforest", "Ecosystem"]
 }
-#############################""",
+
+""",
     """Example 3:
 
 Query: "What is the role of education in reducing poverty?"
-################
+
 Output:
 {
   "high_level_keywords": ["Education", "Poverty reduction", "Socioeconomic development"],
   "low_level_keywords": ["School access", "Literacy rates", "Job training", "Income inequality"]
 }
-#############################""",
+
+""",
 ]
 
 PROMPTS["naive_rag_response"] = """---Role---