M365 Custom Engine Agents Timeout Message after 15 Seconds

Question

Hi,

I used the M365 Agent Toolkit https://learn.microsoft.com/en-us/microsoft-365/developer/overview-m365-agents-toolkit to build a Custom Engine Agent that makes a call to my own LLM service. I was able to deploy and chat with my agents without a problem in MS Teams.

However, from https://copilot.microsoft.com, I am running into issues with the platform giving me a message to check again later.

Upon refreshing the page after a few moments though, I always do see my actual LLM Service's response.

We noticed, it always does this at the 15 second mark.

How do I increase the timeout so that the Copilot UI never returns this message? Are there any other workarounds? Otherwise, this feels like a defect.

Thanks,

Ameer

Answer 1

Hi Ameer,

You're absolutely right about this - it's not a defect on your end. The 15-second timeout is actually a built-in limitation of the M365 Copilot platform that Microsoft hasn't made configurable yet.

Quick Solutions:

Optimize your LLM response time - Target under 12 seconds with a safety margin

// Add this timeout wrapper to your agent

Promise.race([yourLLMCall(), timeoutAfter(12000)])    

Async processing pattern - Return immediate acknowledgment, then deliver the real response:

// Quick reply: "Processing your request..."
// Then send actual LLM response when ready

Performance tweaks:

• Add response caching
• Use streaming if your LLM supports it
• Deploy closer to Microsoft's servers

Best approach: Start with response time optimization since it gives the smoothest user experience. The async pattern works great as a backup for complex queries.

This is definitely a platform constraint we need to work around rather than a bug in your implementation. Your agent is working perfectly - we just need to dance within Microsoft's timing rules!

Thanks,  

Karan Shewale.

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