Microsoft Dynamics 365 | Integration, Dataverse...

I am facing this error sometimes when creating an AI Agent in Copilot Studio.

(3) Share

Report

Posted on by CU24110759-0

{"isNL2AgentError":true,"error":{"code":"UnknownNL2AgentError","isSystemError":false,"message":"{\"name\":\"AxiosError\",\"message\":\"Request failed with status code 400\",\"data\":{\"ErrorCode\":4003,\"ErrorMessage\":\"The request must contain at least one user message with non-empty content.\",\"ErrorInfo\":null,\"Error\":{\"RetryIn\":null,\"InnerErrors\":[],\"Code\":\"InvalidInput\",\"Message\":\"The request must contain at least one user message with non-empty content.\",\"Properties\":{},\"Diagnostics\":null}},\"status\":400,\"statusText\":\"\",\"responseHeaders\":{\"x-ms-correlation-id\":\"7f66dec6-b68d-4afe-b47f-30ade6acddaf\",\"x-ms-service-request-id\":\"acccd659-1f14-4d89-9cca-85a7268716ba\"}}"}}

Categories:

Power Platform integration

I have the same question (7)

All responses (4)

Answers (0)

BM-18110859-0 2 on at

Like (0)

Report
Copy link

Link copied!

Any resolution or work around from Microsoft side?

Was this reply helpful? Yes No
André Arnaud de Cal... 303,706 Super User 2026 Season 1 on at

Like (0)

Report
Copy link

Link copied!

Hi,

Do you still have this issue? If so, can you please provide more information about how you create an agent and at what exact moment you get this error? You can also consider asking your question in the Copilot Studio forum: Microsoft Power Platform Community Forum Thread

Was this reply helpful? Yes No
PerezAguiar Microsoft Employee on at

Like (0)

Report
Copy link

Link copied!

Hey.

It would be important to get more details. Maybe a screenshot? I'm guessing that this is happening on a specific action and has some sort of connector (SharePoint, OneDrive, etc). The error message points to trying to perform an HTTP Action and not passing the right parameters.

Regards,

Was this reply helpful? Yes No
Suggested answer

Valantis 44 on at

Like (0)

Report
Copy link

Link copied!
Hi @CU24110759-0,

The AxiosError 400 (ErrorCode 4003) occurs when Copilot Studio’s backend receives a request that it perceives as "empty." This happens for two main reasons:

Session Sync Issue: The browser fails to send your typed text to the server (a temporary glitch).

Formatting Conflicts: The input contains hidden characters, unsupported line breaks, or invalid syntax that makes the message unreadable to the system.

Solution: Refresh and Re-validate

To resolve this, please follow these steps:

Sanitize Your Text: Copy your agent description into a plain text editor (like Notepad) to strip out hidden formatting or extra line breaks, then paste it back in.

Force a Session Refresh: Refresh your browser page F5 or try the action in an Incognito/Private window. This forces the platform to re-establish a clean connection.

Check Template Fields: If you are using a pre-built template, ensure every required field has at least one character of visible text.

Wait for Save: After typing your prompt, wait 2–3 seconds before clicking "Create" to ensure the UI has registered the input.

Best Regards

Valantis

Was this reply helpful? Yes No