From 0b36d92feffc09198113363fe9a444f4b7eab399 Mon Sep 17 00:00:00 2001
From: Somasundaram Mahesh <msomasundaram93@gmail.com>
Date: Wed, 18 Feb 2026 18:49:13 +0530
Subject: [PATCH] fix: thread AbortSignal through LLM calls so stop_goal
 cancels immediately

The agent loop checked signal.aborted only at the top of each iteration,
but the LLM fetch() call (which takes seconds) never received the signal.
Now the signal is passed to fetch() and checked after LLM errors and
before the inter-step sleep, so aborting takes effect mid-step.
---
 server/src/agent/llm.ts  | 7 +++++--
 server/src/agent/loop.ts | 8 ++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/server/src/agent/llm.ts b/server/src/agent/llm.ts
index 86563ac..371aa75 100644
--- a/server/src/agent/llm.ts
+++ b/server/src/agent/llm.ts
@@ -22,7 +22,8 @@ export interface LLMProvider {
   getAction(
     systemPrompt: string,
     userPrompt: string,
-    imageBase64?: string
+    imageBase64?: string,
+    signal?: AbortSignal
   ): Promise<string>;
 }
 
@@ -381,7 +382,8 @@ export function getLlmProvider(config: LLMConfig): LLMProvider {
     async getAction(
       systemPrompt: string,
       userPrompt: string,
-      imageBase64?: string
+      imageBase64?: string,
+      signal?: AbortSignal
     ): Promise<string> {
       const messages: Array<{ role: string; content: unknown }> = [
         { role: "system", content: systemPrompt },
@@ -418,6 +420,7 @@ export function getLlmProvider(config: LLMConfig): LLMProvider {
           max_tokens: 1024,
           response_format: { type: "json_object" },
         }),
+        signal,
       });
 
       if (!response.ok) {
diff --git a/server/src/agent/loop.ts b/server/src/agent/loop.ts
index 7cdcddf..d856a2e 100644
--- a/server/src/agent/loop.ts
+++ b/server/src/agent/loop.ts
@@ -489,9 +489,11 @@ export async function runAgentLoop(
         rawResponse = await llm.getAction(
           systemPrompt,
           userPrompt,
-          useScreenshot ? screenshot : undefined
+          useScreenshot ? screenshot : undefined,
+          signal
         );
       } catch (err) {
+        if (signal?.aborted) break;
         console.error(
           `[Agent ${sessionId}] LLM error at step ${step + 1}: ${(err as Error).message}`
         );
@@ -510,7 +512,8 @@ export async function runAgentLoop(
           rawResponse = await llm.getAction(
             systemPrompt,
             userPrompt + "\n\nIMPORTANT: Your previous response was not valid JSON. You MUST respond with ONLY a valid JSON object.",
-            useScreenshot ? screenshot : undefined
+            useScreenshot ? screenshot : undefined,
+            signal
           );
           parsed = parseJsonResponse(rawResponse);
         } catch {
@@ -634,6 +637,7 @@ export async function runAgentLoop(
       }
 
       // ── 10. Brief pause for UI to settle ────────────────────
+      if (signal?.aborted) break;
       await new Promise((r) => setTimeout(r, 500));
     }
   } catch (error) {