Append data exceeds maximum size

Support Help
,
1

The CLI agent command fails with ‘Append data exceeds maximum size of 52428800 bytes’ on every message, but the IDE agents work fine. I tried using the CLI agent version 2026.04.17 and 2026.04.15. Steps to try to fix the issue that didn’t work:

  • Cleared out my cursor directory with rm -rf ~/.cursor and recreated it cursor agent login
    • I think that rules out skills or history causing issues
  • Killed any background agents that were running that I might not have been aware of ps aux | grep -i cursor then kill pid
  • Ran the agent with the test message hi in an empty directory

I have the useHttp1ForAgent setting set to true for the agent because I’m on a VPN, otherwise the agent fails to connect. Using the troubleshooting steps above I’m still stuck with the error: “Error: Bad Request
Append data exceeds maximum size of 52428800 bytes”

8

Hi Scott, thanks for the report, and sorry for the trouble.

I’ve linked this to an existing investigation on our side. Based on what you shared, this looks related to the CLI agent’s HTTP/1 transport path that you enabled for VPN compatibility. Clearing ~/.cursor or starting from an empty directory likely won’t help, since this does not appear to be caused by local history or project files.

For now, the main workaround is to use a network or VPN configuration that allows the CLI agent to use the default HTTP/2 connection path, if that’s possible. We know that may not be available in your setup, so we’re tracking this with engineering.

We do have an internal request that’s open for this that can help alleviate the problem and I’ll let you know if that gets picked up.