DeepSeek models on Chutes provider output raw DSML tags instead of executing tools #14050

Description

When using DeepSeek models through the Chutes provider, the agent fails to recognize and execute tool calls. Instead of performing the requested actions, it outputs raw XML-style tags (DSML - DeepSeek Markup Language) and stops processing.

I have to manually tell the agent to "keep working" to get it to move to the next step, but it often just outputs more raw tags.

Here is an example output when calling a tool:

<｜DSML｜function_calls>
<｜DSML｜invoke name="glob">
<｜DSML｜parameter name="pattern" string="true">*/starship.toml</｜DSML｜parameter>
</｜DSML｜invoke>

And with an MCP server:

<｜DSML｜function_calls>
<｜DSML｜invoke name="zai_webSearchPrime">
<｜DSML｜parameter name="search_query" string="true">starship scan_timeout warning scanning current directory</｜DSML｜parameter>
<｜DSML｜parameter name="content_size" string="true">medium</｜DSML｜parameter>
<｜DSML｜parameter name="location" string="true">us</｜DSML｜parameter>
</｜DSML｜invoke>
</｜DSML｜function_calls>

I have found a known issue in another project that seems to explain what happens:
https://docs.openwebui.com/features/extensibility/plugin/tools/#known-model-specific-issues

This problem is very visible with DeepSeek, but I had similar issues with Kimi K2.5 via the Chutes provider too, where it output different XML tags (I don't have the session anymore), while Kimi on Zen works flawlessly.

Plugins

No response

OpenCode version

1.2.6

Steps to reproduce

1. Connect OpenCode to the Chutes provider.
2. Select DeepSeek v3.2 model.
3. Issue a prompt that requires tools or MCP calls.
4. Observe the raw DSML output in the terminal.

Screenshot and/or share link

No response

Operating System

No response

Terminal

No response