fix: pass MAX_MESSAGE_PAIRS_PER_AGENT to streaming conversation save

[octo-patch]

Fixes #365

Problem

The processStreamInBackground method in orchestrator.ts was calling saveConversationExchange without the maxHistorySize parameter. Streaming responses ignored MAX_MESSAGE_PAIRS_PER_AGENT, causing unbounded conversation history growth.

Solution

Added the missing this.config.MAX_MESSAGE_PAIRS_PER_AGENT parameter to saveConversationExchange inside processStreamInBackground, matching the non-streaming code path.

Testing

The fix is a one-line addition aligning the streaming code path with the already-correct non-streaming path.

[cornelcroi]

@claude check this PR. You must check of the problem statement is real, then to analyze the implementation and see if it really fixes the issue.

[claude]

Claude finished @cornelcroi's task in 1m 30s —— View job

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PR Review: fix/issue-365-streaming-max-message-pairs

Todo List:

• Gather context and understand the request
• Verify the problem statement is real (check original code for the bug)
• Analyze the implementation/fix
• Check if the Python implementation has the same issue
• Post final review findings

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Problem Statement — Confirmed Real ✓

The bug is genuine. Looking at the diff:

-            agent.id
+            agent.id,
+            this.config.MAX_MESSAGE_PAIRS_PER_AGENT

The processStreamInBackground method in typescript/src/orchestrator.ts was calling saveConversationExchange with only 6 arguments, leaving the 7th (maxHistorySize) as undefined. The function signature at typescript/src/utils/chatUtils.ts:5-12 is:

export async function saveConversationExchange(
  userInput: string,
  agentResponse: string,
  storage: ChatStorage,
  userId: string,
  sessionId: string,
  agentId: string,
  maxHistorySize?: number  // ← was always undefined for streaming
)

Without maxHistorySize, the storage backend has no upper bound on how many messages it retains per agent session, causing unbounded history growth for any streaming agent.

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Fix Analysis ✓

The fix is correct and minimal. The non-streaming path at orchestrator.ts:428-436 was already passing this.config.MAX_MESSAGE_PAIRS_PER_AGENT correctly. The streaming path inside processStreamInBackground (lines 533–541 after the fix) is now consistent with it.

The fire-and-forget nature of processStreamInBackground (it's not awaited at the call site on line 411) is intentional — it allows the AccumulatorTransform stream to be returned immediately. The fix correctly applies to the save call inside that background method.

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Python Parity — Not Affected ✓

The Python implementation doesn't have this bug. Its save_message helper at python/src/agent_squad/orchestrator.py:350-359 always includes self.config.MAX_MESSAGE_PAIRS_PER_AGENT:

async def save_message(self, message, user_id, session_id, agent):
    if agent and agent.save_chat:
        return await self.storage.save_chat_message(
            user_id, session_id, agent.id, message,
            self.config.MAX_MESSAGE_PAIRS_PER_AGENT  # always passed
        )

The Python streaming path calls this helper at lines 189 and 208, so it was never vulnerable.

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Minor Observation ⚠️

No tests were added for the streaming conversation-save code path. The fix is a correct alignment with the non-streaming path, but a test covering that MAX_MESSAGE_PAIRS_PER_AGENT is respected in the streaming path would prevent future regressions. This is a nice-to-have rather than a blocker.

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Verdict: The problem statement is real, the fix is correct and complete for the TypeScript implementation, and no Python changes are needed. The PR is ready to merge.