In Open-WebUI, an Automatic Function Calling warning can appear because the model is allowed to make zero remote calls. When that limit is set to 0, tool use can fail before it starts.

The working fix is to change the maximum remote calls value to 1 or higher.

Where to change it

  1. Open the model or chat settings in Open-WebUI.
  2. Find the advanced parameters section.
  3. Look for max remote calls.
  4. Set the value to 1 or more.
Abstract interface illustration
The original post referenced the advanced parameter panel where the remote call limit can be changed.

Why the warning happens

A value of zero effectively blocks remote tool calls. If your workflow depends on automatic function calling, that means the system reaches a hard stop and surfaces the AFC warning instead of continuing.

Recommended setting

Start with 1. If your workflow genuinely needs more than a single remote call, raise the number deliberately instead of leaving it at zero.

That one change should clear the warning and allow Open-WebUI to continue making the remote call it needs.