From 2ed47980ef8ce0d942ce7e9266ba18bd9b42011f Mon Sep 17 00:00:00 2001
From: William Jeynes <william.jeynes@hotmail.com>
Date: Tue, 31 Mar 2026 19:26:56 +0100
Subject: [PATCH] Add better error handling to LLM output response

---
 agent/nodes/verificationSetup.ts | 42 +++++++++++++++++++-------------
 1 file changed, 25 insertions(+), 17 deletions(-)

diff --git a/agent/nodes/verificationSetup.ts b/agent/nodes/verificationSetup.ts
index e142e37..66fe64d 100644
--- a/agent/nodes/verificationSetup.ts
+++ b/agent/nodes/verificationSetup.ts
@@ -1,20 +1,24 @@
 import { GraphNode } from "@langchain/langgraph";
 import { MessagesState, ProposedTriggerEventArray } from "../state";
 import { logger } from "../utils/logger";
-import { jsonrepair } from 'jsonrepair'
+import { jsonrepair } from 'jsonrepair';
 
 export const verificationSetup: GraphNode<typeof MessagesState> = async (state) => {
-  //this is kinda doing two things, but having two nodes for it seems overkill
-
   if (state.proposedTriggerEvent == undefined) {
-    logger.warn("No trigger events in memory, parsing")
+    logger.warn("No trigger events in memory, parsing");
 
-    let genResponse = state.messages.at(-1)?.content.toString() ?? "";
+    const genResponse = state.messages.at(-1)?.content.toString() ?? "";
 
-    const repaired = jsonrepair(genResponse);
+    let repaired: string;
+    try {
+      repaired = jsonrepair(genResponse);
+    } catch (repairErr: any) {
+      logger.error("Failed to repair JSON from LLM response.");
+      logger.error("Original LLM response:\n%s", genResponse);
+      throw new Error(`JSON repair failed: ${repairErr.message}`);
+    }
 
     let parsed;
-
     try {
       const json = JSON.parse(repaired);
 
@@ -27,19 +31,23 @@ export const verificationSetup: GraphNode<typeof MessagesState> = async (state)
         if (Array.isArray(firstValue)) {
           parsed = ProposedTriggerEventArray.parse(firstValue);
         } else {
-          throw new Error("No array found in JSON");
+          logger.error("No array found in JSON after parsing.");
+          logger.error("Repaired JSON:\n%s", repaired);
+          logger.error("Original LLM response:\n%s", genResponse);
+          throw new Error("No array found in JSON structure");
         }
       }
-    } catch (err: any) {
-      logger.error(`Failed to parse LLM response: ${err.message}`);
-      throw new Error(`Failed to parse LLM response: ${err}`);
+    } catch (parseErr: any) {
+      logger.error("Failed to parse LLM response to JSON or validate array.");
+      logger.error("Repaired JSON:\n%s", repaired);
+      logger.error("Original LLM response:\n%s", genResponse);
+      throw new Error(`Parsing failed: ${parseErr.message}`);
     }
-    
+
     return { proposedTriggerEvent: parsed, proposedTriggerEventIndex: 0 };
-  }
-  else {
-    logger.info("Trigger event index %s", state.proposedTriggerEventIndex+1)
-    
-    return { proposedTriggerEvent: state.proposedTriggerEvent, proposedTriggerEventIndex: state.proposedTriggerEventIndex+1 };
+  } else {
+    logger.info("Trigger event index %s", state.proposedTriggerEventIndex + 1);
+
+    return { proposedTriggerEvent: state.proposedTriggerEvent, proposedTriggerEventIndex: state.proposedTriggerEventIndex + 1 };
   }
 };
\ No newline at end of file