fix(a2a-middleware): ensure tool results are passed to orchestrator in subsequent runs (#465)

Bug: The A2A middleware was not including tool results in input.messages when
triggering subsequent runs. This caused the orchestration agent to not see the
tool results in its context, leading to repeated tool calls and broken multi-turn
conversations with A2A agents.

Fix: Collect all tool result messages and add them to input.messages before
calling triggerNewRun(). This ensures the orchestrator receives the tool results
in the conversation context for the next run.

Also removes unused 'text' import from stream/consumers.

Author: markmdev

typescript-sdk/integrations/a2a-middleware/src/index.ts

@@ -20,7 +20,6 @@ import { AgentCard, SendMessageResponse, SendMessageSuccessResponse } from "@a2a
 import { Observable, Subscriber, tap } from "rxjs";
 import { createSystemPrompt, sendMessageToA2AAgentTool } from "./utils";
 import { randomUUID } from "crypto";
-import { text } from "stream/consumers";
 
 export interface A2AAgentConfig extends AgentConfig {
   agentUrls: string[];
@@ -129,6 +128,9 @@ export class A2AMiddlewareAgent extends AbstractAgent {
             this.finishTextMessages(observer, pendingTextMessages);
 
             if (pendingA2ACalls.size > 0) {
+              // Array to collect all new tool result messages
+              const newToolMessages: Message[] = [];
+
               const callProms = [...pendingA2ACalls].map((toolCallId) => {
                 const toolCallsFromMessages = this.messages
                   .filter((message) => message.role === "assistant")
@@ -160,6 +162,9 @@ export class A2AMiddlewareAgent extends AbstractAgent {
                     this.addMessage(newMessage);
                     this.orchestrationAgent.addMessage(newMessage);
 
+                    // Collect the message so we can add it to input.messages
+                    newToolMessages.push(newMessage);
+
                     const newEvent: ToolCallResultEvent = {
                       type: EventType.TOOL_CALL_RESULT,
                       toolCallId: toolCallId,
@@ -184,6 +189,12 @@ export class A2AMiddlewareAgent extends AbstractAgent {
                   runId: input.runId,
                 } as RunFinishedEvent);
 
+                // Add all tool result messages to input.messages BEFORE triggering new run
+                // This ensures the orchestrator sees the tool results in its context
+                newToolMessages.forEach((msg) => {
+                  input.messages.push(msg);
+                });
+
                 this.triggerNewRun(observer, input, pendingA2ACalls, pendingTextMessages);
               });
             } else {