Gemma 4 chat template for llama.cpp (from https://github.com/ggml-org/llama.cpp/blob/master/models/templates/google-gemma-4-31B-it-interleaved.jinja)

gemma4-chat-template.jinja

{%- macro format_parameters(properties, required) -%}
    {%- set standard_keys = ['description', 'type', 'properties', 'required', 'nullable'] -%}
    {%- set ns = namespace(found_first=false) -%}
    {%- for key, value in properties | dictsort -%}
        {%- set add_comma = false -%}
        {%- if key not in standard_keys -%}
            {%- if ns.found_first %},{% endif -%}
            {%- set ns.found_first = true -%}
            {{ key }}:{
            {%- if value['description'] -%}
                description:<|"|>{{ value['description'] }}<|"|>
                {%- set add_comma = true -%}
            {%- endif -%}
            {%- if value['nullable'] %}
                {%- if add_comma %},{%- else -%} {%- set add_comma = true -%} {% endif -%}
                nullable:true
            {%- endif -%}
            {%- if value['type'] | upper == 'STRING' -%}
                {%- if value['enum'] -%}
                    {%- if add_comma %},{%- else -%} {%- set add_comma = true -%} {% endif -%}
                    enum:{{ format_argument(value['enum']) }}
                {%- endif -%}
            {%- elif value['type'] | upper == 'OBJECT' -%}
                ,properties:{
                {%- if value['properties'] is defined and value['properties'] is mapping -%}
                    {{- format_parameters(value['properties'], value['required'] | default([])) -}}
                {%- elif value is mapping -%}
                    {{- format_parameters(value, value['required'] | default([])) -}}
                {%- endif -%}
                }
                {%- if value['required'] -%}
                    ,required:[
                    {%- for item in value['required'] | default([]) -%}
                        <|"|>{{- item -}}<|"|>
                        {%- if not loop.last %},{% endif -%}
                    {%- endfor -%}
                    ]
                {%- endif -%}
            {%- elif value['type'] | upper == 'ARRAY' -%}
                {%- if value['items'] is mapping and value['items'] -%}
                    ,items:{
                    {%- set ns_items = namespace(found_first=false) -%}
                    {%- for item_key, item_value in value['items'] | dictsort -%}
                        {%- if item_value is not none -%}
                            {%- if ns_items.found_first %},{% endif -%}
                            {%- set ns_items.found_first = true -%}
                            {%- if item_key == 'properties' -%}
                                properties:{
                                {%- if item_value is mapping -%}
                                    {{- format_parameters(item_value, value['items']['required'] | default([])) -}}
                                {%- endif -%}
                                }
                            {%- elif item_key == 'required' -%}
                                required:[
                                {%- for req_item in item_value -%}
                                    <|"|>{{- req_item -}}<|"|>
                                    {%- if not loop.last %},{% endif -%}
                                {%- endfor -%}
                                ]
                            {%- elif item_key == 'type' -%}
                                {%- if item_value is string -%}
                                    type:{{ format_argument(item_value | upper) }}
                                {%- else -%}
                                    type:{{ format_argument(item_value | map('upper') | list) }}
                                {%- endif -%}
                            {%- else -%}
                                {{ item_key }}:{{ format_argument(item_value) }}
                            {%- endif -%}
                        {%- endif -%}
                    {%- endfor -%}
                    }
                {%- endif -%}
            {%- endif -%}
            {%- if add_comma %},{%- else -%} {%- set add_comma = true -%} {% endif -%}
            type:<|"|>{{ value['type'] | upper }}<|"|>}
        {%- endif -%}
    {%- endfor -%}
{%- endmacro -%}
{%- macro format_function_declaration(tool_data) -%}
    declaration:{{- tool_data['function']['name'] -}}{description:<|"|>{{- tool_data['function']['description'] -}}<|"|>
    {%- set params = tool_data['function']['parameters'] -%}
    {%- if params -%}
        ,parameters:{
        {%- if params['properties'] -%}
            properties:{ {{- format_parameters(params['properties'], params['required']) -}} },
        {%- endif -%}
        {%- if params['required'] -%}
            required:[
            {%- for item in params['required'] -%}
                <|"|>{{- item -}}<|"|>
                {{- ',' if not loop.last -}}
            {%- endfor -%}
            ],
        {%- endif -%}
        {%- if params['type'] -%}
            type:<|"|>{{- params['type'] | upper -}}<|"|>}
        {%- endif -%}
    {%- endif -%}
    {%- if 'response' in tool_data['function'] -%}
        {%- set response_declaration = tool_data['function']['response'] -%}
        ,response:{
        {%- if response_declaration['description'] -%}
            description:<|"|>{{- response_declaration['description'] -}}<|"|>,
        {%- endif -%}
        {%- if response_declaration['type'] | upper == 'OBJECT' -%}
            type:<|"|>{{- response_declaration['type'] | upper -}}<|"|>}
        {%- endif -%}
    {%- endif -%}
    }
{%- endmacro -%}
{%- macro format_argument(argument, escape_keys=True) -%}
    {%- if argument is string -%}
        {{- '<|"|>' + argument + '<|"|>' -}}
    {%- elif argument is boolean -%}
        {{- 'true' if argument else 'false' -}}
    {%- elif argument is mapping -%}
        {{- '{' -}}
        {%- set ns = namespace(found_first=false) -%}
        {%- for key, value in argument | dictsort -%}
            {%- if ns.found_first %},{% endif -%}
            {%- set ns.found_first = true -%}
            {%- if escape_keys -%}
                {{- '<|"|>' + key + '<|"|>' -}}
            {%- else -%}
                {{- key -}}
            {%- endif -%}
            :{{- format_argument(value, escape_keys=escape_keys) -}}
        {%- endfor -%}
        {{- '}' -}}
    {%- elif argument is sequence -%}
        {{- '[' -}}
        {%- for item in argument -%}
            {{- format_argument(item, escape_keys=escape_keys) -}}
            {%- if not loop.last %},{% endif -%}
        {%- endfor -%}
        {{- ']' -}}
    {%- else -%}
        {{- argument -}}
    {%- endif -%}
{%- endmacro -%}
{%- macro strip_thinking(text) -%}
    {%- set ns = namespace(result='') -%}
    {%- for part in text.split('<channel|>') -%}
        {%- if '<|channel>' in part -%}
            {%- set ns.result = ns.result + part.split('<|channel>')[0] -%}
        {%- else -%}
            {%- set ns.result = ns.result + part -%}
        {%- endif -%}
    {%- endfor -%}
    {{- ns.result | trim -}}
{%- endmacro -%}

{%- set ns = namespace(prev_message_type=None, last_user_message=-1) -%}
{%- set loop_messages = messages -%}
{{ bos_token }}
{#- Handle System/Tool Definitions Block -#}
{%- if (enable_thinking is defined and enable_thinking) or tools or messages[0]['role'] in ['system', 'developer'] -%}
    {{- '<|turn>system\n' -}}

    {#- Inject Thinking token at the very top of the FIRST system turn -#}
    {%- if enable_thinking is defined and enable_thinking -%}
        {{- '<|think|>' -}}
        {%- set ns.prev_message_type = 'think' -%}
    {%- endif -%}

    {%- if messages[0]['role'] in ['system', 'developer'] -%}
        {{- messages[0]['content'] | trim -}}
        {%- set loop_messages = messages[1:] -%}
    {%- endif -%}

    {%- if tools -%}
        {%- for tool in tools %}
            {{- '<|tool>' -}}
            {{- format_function_declaration(tool) | trim -}}
            {{- '<tool|>' -}}
        {%- endfor %}
        {%- set ns.prev_message_type = 'tool' -%}
    {%- endif -%}

    {{- '<turn|>\n' -}}
{%- endif %}

{#- Find last user message -#}
{%- for message in loop_messages -%}
    {%- if message['role'] == 'user' -%}
        {%- set ns.last_user_message = loop.index0 -%}
    {%- endif -%}
{%- endfor -%}

{#- Loop through messages -#}
{%- for message in loop_messages -%}
    {%- set role = 'model' if message['role'] == 'assistant' else message['role'] -%}
        {%- if not (ns.prev_message_type == 'tool_response' and message['tool_calls']) -%}
        {{- '<|turn>' + role + '\n' }}
        {%- endif -%}

        {%- set ns.prev_message_type = None -%}

            {%- if message['tool_calls'] -%}
                {#- Preserve reasoning between tool calls for model turns that come after the last user turn -#}
                {%- if message['reasoning_content'] and loop.index0 > ns.last_user_message -%}
                  {{- '<|channel>thought\n' -}}
                  {{- message['reasoning_content'] -}}
                  {{- '<channel|>' -}}
                {%- endif -%}
                {%- for tool_call in message['tool_calls'] -%}
                    {%- set function = tool_call['function'] -%}
                    {{- '<|tool_call>call:' + function['name'] + '{' -}}
                    {%- if function['arguments'] is mapping -%}
                        {%- set ns_args = namespace(found_first=false) -%}
                        {%- for key, value in function['arguments'] | dictsort -%}
                            {%- if ns_args.found_first %},{% endif -%}
                            {%- set ns_args.found_first = true -%}
                            {{- key -}}:{{- format_argument(value, escape_keys=False) -}}
                        {%- endfor -%}
                    {%- elif function['arguments'] is string -%}
                        {{- function['arguments'] -}}
                    {%- endif -%}
                    {{- '}<tool_call|>' -}}
                {%- endfor -%}
                {%- set ns.prev_message_type = 'tool_call' -%}
            {%- endif -%}

            {%- if message['tool_responses'] -%}
                {#- Tool Response handling -#}
                {%- for tool_response in message['tool_responses'] -%}
                    {{- '<|tool_response>' -}}
                    {%- if tool_response['response'] is mapping -%}
                        {{- 'response:' + tool_response['name'] | default('unknown') + '{' -}}
                        {%- for key, value in tool_response['response'] | dictsort -%}
                            {{- key -}}:{{- format_argument(value, escape_keys=False) -}}
                            {%- if not loop.last %},{% endif -%}
                        {%- endfor -%}
                        {{- '}' -}}
                    {%- else -%}
                        {{- 'response:' + tool_response['name'] | default('unknown') + '{value:' + format_argument(tool_response['response'], escape_keys=False) + '}' -}}
                    {%- endif -%}
                    {{- '<tool_response|>' -}}
                {%- endfor -%}
                {%- set ns.prev_message_type = 'tool_response' -%}
            {%- endif -%}

            {%- if message['content'] is string -%}
                {%- if role == 'model' -%}
                    {{- strip_thinking(message['content']) -}}
                {%- else -%}
                    {{- message['content'] | trim -}}
                {%- endif -%}
            {%- elif message['content'] is sequence -%}
                {%- for item in message['content'] -%}
                    {%- if item['type'] == 'text' -%}
                        {%- if role == 'model' -%}
                            {{- strip_thinking(item['text']) -}}
                        {%- else -%}
                            {{- item['text'] | trim -}}
                        {%- endif -%}
                    {%- elif item['type'] == 'image' -%}
                        {{- '\n\n<|image|>\n\n' -}}
                        {%- set ns.prev_message_type = 'image' -%}
                    {%- elif item['type'] == 'audio' -%}
                        {{- '<|audio|>' -}}
                        {%- set ns.prev_message_type = 'audio' -%}
                    {%- elif item['type'] == 'video' -%}
                        {{- '\n\n<|video|>\n\n' -}}
                        {%- set ns.prev_message_type = 'video' -%}
                    {%- endif -%}
                {%- endfor -%}
            {%- endif -%}

        {%- if not (message['tool_responses'] and not message['content']) -%}
            {{- '<turn|>\n' -}}
        {%- endif -%}
{%- endfor -%}

{%- if add_generation_prompt -%}
    {%- if ns.prev_message_type != 'tool_response' -%}
        {{- '<|turn>model\n' -}}
    {%- endif -%}
    {%- if not enable_thinking | default(false) -%}
        {{- '<|channel>thought\n<channel|>' -}}
    {%- endif -%}
{%- endif -%}