data pipeline refactor and fix

gateway/src/harness/subagents/web-explore/index.ts

@@ -3,6 +3,7 @@ import type { BaseChatModel } from '@langchain/core/language_models/chat_models'
 import { SystemMessage } from '@langchain/core/messages';
 import { createReactAgent } from '@langchain/langgraph/prebuilt';
 import type { FastifyBaseLogger } from 'fastify';
+import type { HarnessEvent } from '../../harness-events.js';
 
 /**
  * Web Explore Subagent
@@ -66,6 +67,52 @@ export class WebExploreSubagent extends BaseSubagent {
 
     return finalText;
   }
+
+  async *streamEvents(context: SubagentContext, instruction: string, signal?: AbortSignal): AsyncGenerator<HarnessEvent, string> {
+    this.logger.info({ subagent: this.getName() }, 'streamEvents starting');
+
+    const initialMessages = this.buildMessages(context, instruction);
+    const systemMessage = initialMessages[0];
+    const humanMessage = initialMessages[initialMessages.length - 1];
+
+    const agent = createReactAgent({
+      llm: this.model,
+      tools: this.tools,
+      prompt: systemMessage as SystemMessage,
+    });
+
+    const stream = agent.stream(
+      { messages: [humanMessage] },
+      { streamMode: ['messages', 'updates'], recursionLimit: 15, signal }
+    );
+
+    let finalText = '';
+
+    for await (const [mode, data] of await stream) {
+      if (signal?.aborted) break;
+      if (mode === 'messages') {
+        for (const chunk of WebExploreSubagent.extractStreamChunks(data, this.config.name)) {
+          yield chunk;
+        }
+      } else if (mode === 'updates') {
+        if ((data as any).agent?.messages) {
+          for (const msg of (data as any).agent.messages as any[]) {
+            if (msg.tool_calls?.length) {
+              for (const tc of msg.tool_calls) {
+                yield { type: 'subagent_tool_call', agentName: this.config.name, toolName: tc.name, label: tc.name };
+              }
+            } else {
+              const content = WebExploreSubagent.extractFinalText(msg);
+              if (content) finalText = content;
+            }
+          }
+        }
+      }
+    }
+
+    this.logger.info({ textLength: finalText.length }, 'streamEvents finished');
+    return finalText;
+  }
 }
 
 /**