chat_template.jinja

{# Custom Qwen3 math chat template with thinking enabled #}
{%- set enable_thinking = true -%}
{%- set system_message = "You are a mathematical reasoning assistant. Think through the problem in a scratchpad, decompose it step by step, and reason within the available budget. Prefer shorter reasoning when sufficient, but use longer reasoning when the problem requires it. Put the final answer exactly once in \\boxed{ANSWER}. Do not write anything after the boxed answer." -%}

{# System message block #}
{%- if tools %}
    {{- '<|im_start|>system\n' }}
    {{- system_message }}
    {%- if messages[0].role == 'system' %}
        {{- '\n' + messages[0].content }}
    {%- endif %}
    {{- "\n\n# Tools\n\nYou may call one or more functions to assist with the user query.\n\nYou are provided with function signatures within <tools></tools> XML tags:\n<tools>" }}
    {%- for tool in tools %}
        {{- "\n" }}
        {{- tool | tojson }}
    {%- endfor %}
    {{- "\n</tools>\n\nFor each function call, return a json object with function name and arguments within <tool_call></tool_call> XML tags:\n<tool_call>\n{\"name\": <function-name>, \"arguments\": <args-json-object>}\n</tool_call><|im_end|>\n" }}
{%- else %}
    {{- '<|im_start|>system\n' }}
    {{- system_message }}
    {%- if messages[0].role == 'system' %}
        {{- '\n' + messages[0].content }}
    {%- endif %}
    {{- '<|im_end|>\n' }}
{%- endif %}

{%- set ns = namespace(multi_step_tool=true, last_query_index=messages|length - 1) %}
{%- for message in messages[::-1] %}
    {%- set index = (messages|length - 1) - loop.index0 %}
    {%- if ns.multi_step_tool and message.role == "user" and message.content is string and not(message.content.startswith('<tool_response>') and message.content.endswith('</tool_response>')) %}
        {%- set ns.multi_step_tool = false %}
        {%- set ns.last_query_index = index %}
    {%- endif %}
{%- endfor %}

{%- for message in messages %}
    {%- if message.content is string %}
        {%- set content = message.content %}
    {%- else %}
        {%- set content = '' %}
    {%- endif %}

    {%- if message.role == "system" and loop.first %}
        {# do nothing; already merged above #}

    {%- elif message.role == "user" or message.role == "system" %}
        {{- '<|im_start|>' + message.role + '\n' + content + '<|im_end|>\n' }}

    {%- elif message.role == "assistant" %}
        {{- '<|im_start|>assistant\n' + content }}

        {%- if message.tool_calls %}
            {%- for tool_call in message.tool_calls %}
                {%- if (loop.first and content) or (not loop.first) %}
                    {{- '\n' }}
                {%- endif %}
                {%- if tool_call.function %}
                    {%- set tool_call = tool_call.function %}
                {%- endif %}
                {{- '<tool_call>\n{"name": "' }}
                {{- tool_call.name }}
                {{- '", "arguments": ' }}
                {%- if tool_call.arguments is string %}
                    {{- tool_call.arguments }}
                {%- else %}
                    {{- tool_call.arguments | tojson }}
                {%- endif %}
                {{- '}\n</tool_call>' }}
            {%- endfor %}
        {%- endif %}
        {{- '<|im_end|>\n' }}

    {%- elif message.role == "tool" %}
        {%- if loop.first or (messages[loop.index0 - 1].role != "tool") %}
            {{- '<|im_start|>user' }}
        {%- endif %}
        {{- '\n<tool_response>\n' }}
        {{- content }}
        {{- '\n</tool_response>' }}
        {%- if loop.last or (messages[loop.index0 + 1].role != "tool") %}
            {{- '<|im_end|>\n' }}
        {%- endif %}
    {%- endif %}
{%- endfor %}

{%- if add_generation_prompt %}
    {{- '<|im_start|>assistant\n' }}
{%- endif %}