hermes - 💡(How to fix) Fix [Bug]: MiniMax/DeepSeek V4 XML tool calls are rendered as text instead of executed in Web UI/gateway

Bug Description

When using Hermes Agent via hermes-web-ui on Windows, tool calls are sometimes rendered directly as assistant text instead of being parsed and executed.

This happens with MiniMax-M2.7 and also appears with DeepSeek V4 / deepseek-v4-flash style models. The visible output includes raw tool-call text such as:

<minimax:tool_call>
  <invoke name="terminal">
    <parameter name="command">cmd /c "feishu --help"</parameter>
  </invoke>
</minimax:tool_call>

or:

[Calling tool: execute_code with arguments: {...}]

The tool is not executed, the conversation stops, and the raw tool-call markup is shown in the chat UI.

Steps to Reproduce

1. Run Hermes Agent on Windows 11.
2. Start hermes-web-ui.
3. Use MiniMax-M2.7 or DeepSeek V4 / deepseek-v4-flash as the main model.
4. Ask the agent to perform a tool task, for example:
   • inspect a local file
   • run a terminal command
   • install/check a CLI tool
5. Observe that the assistant sometimes emits raw tool-call markup instead of executing the tool.

Expected Behavior

Hermes should parse the model's tool-call format and execute the corresponding tool. Raw tool-call markup should not be shown as normal assistant text.

Actual Behavior

The raw tool-call markup is displayed in the Web UI as a normal assistant message, and the tool call is not executed.

Environment

• OS: Windows 11
• Hermes Agent: v0.14.0
• hermes-web-ui: v0.5.28
• Python: 3.13.2
• OpenAI SDK: 2.24.0
• Models tested:
  • MiniMax-M2.7 via minimax-cn
  • deepseek-v4-flash via OpenAI-compatible custom provider

Notes

This seems related to issue #12090, but it is reproducible in hermes-web-ui/gateway on Windows and not only Telegram.

MiniMax uses XML-style tool calls such as <minimax:tool_call>. DeepSeek V4 also appears to use a newer XML/DSML-style tool-call format. It looks like some Hermes agent loop or gateway path does not normalize these provider-specific tool-call formats into Hermes internal tool calls.

Workarounds Tried

• Reinstalled Hermes Agent cleanly
• Reinstalled hermes-web-ui
• Tried hermes-web-ui v0.5.22 and v0.5.28
• Set agent.tool_use_enforcement: always
• Restarted gateway and Web UI
• Created new sessions

The issue still occurs.