1{% macro render_extra_keys(json_dict, handled_keys) %}
  2    {%- if json_dict is mapping %}
  3        {%- for json_key in json_dict if json_key not in handled_keys %}
  4            {%- if json_dict[json_key] is mapping or (json_dict[json_key] is sequence and json_dict[json_key] is not string) %}
  5                {{- '\n<' ~ json_key ~ '>' ~ (json_dict[json_key] | tojson | safe) ~ '</' ~ json_key ~ '>' }}
  6            {%- else %}
  7                {{-'\n<' ~ json_key ~ '>' ~ (json_dict[json_key] | string) ~ '</' ~ json_key ~ '>' }}
  8            {%- endif %}
  9        {%- endfor %}
 10    {%- endif %}
 11{% endmacro %}
 12{%- set enable_thinking = enable_thinking if enable_thinking is defined else True %}
 13{%- set truncate_history_thinking = truncate_history_thinking if truncate_history_thinking is defined else True %}
 14
 15{%- set ns = namespace(last_user_idx = -1) %}
 16{%- set loop_messages = messages %}
 17{%- for m in loop_messages %}
 18  {%- if m["role"] == "user" %}
 19    {%- set ns.last_user_idx = loop.index0 %}
 20  {%- endif %}
 21{%- endfor %}
 22
 23{%- if messages[0]["role"] == "system" %}
 24    {%- set system_message = messages[0]["content"] %}
 25    {%- set loop_messages = messages[1:] %}
 26{%- else %}
 27    {%- set system_message = "" %}
 28    {%- set loop_messages = messages %}
 29{%- endif %}
 30{%- if not tools is defined %}
 31    {%- set tools = [] %}
 32{%- endif %}
 33{# Recompute last_user_idx relative to loop_messages after handling system #}
 34{%- set ns = namespace(last_user_idx = -1) %}
 35{%- for m in loop_messages %}
 36  {%- if m["role"] == "user" %}
 37    {%- set ns.last_user_idx = loop.index0 %}
 38  {%- endif %}
 39{%- endfor %}
 40{%- if system_message is defined %}
 41    {{- "<|im_start|>system\n" + system_message }}
 42{%- else %}
 43    {%- if tools is iterable and tools | length > 0 %}
 44        {{- "<|im_start|>system\n" }}
 45    {%- endif %}
 46{%- endif %}
 47{%- if tools is iterable and tools | length > 0 %}
 48    {%- if system_message is defined and system_message | length > 0 %}
 49        {{- "\n\n" }}
 50    {%- endif %}
 51    {{- "# Tools\n\nYou have access to the following functions:\n\n" }}
 52    {{- "<tools>" }}
 53    {%- for tool in tools %}
 54        {%- if tool.function is defined %}
 55            {%- set tool = tool.function %}
 56        {%- endif %}
 57        {{- "\n<function>\n<name>" ~ tool.name ~ "</name>" }}
 58        {%- if tool.description is defined %}
 59            {{- '\n<description>' ~ (tool.description | trim) ~ '</description>' }}
 60        {%- endif %}
 61        {{- '\n<parameters>' }}
 62        {%- if tool.parameters is defined and tool.parameters is mapping and tool.parameters.properties is defined and tool.parameters.properties is mapping %}
 63            {%- for param_name, param_fields in tool.parameters.properties|items %}
 64                {{- '\n<parameter>' }}
 65                {{- '\n<name>' ~ param_name ~ '</name>' }}
 66                {%- if param_fields.type is defined %}
 67                    {{- '\n<type>' ~ (param_fields.type | string) ~ '</type>' }}
 68                {%- endif %}
 69                {%- if param_fields.description is defined %}
 70                    {{- '\n<description>' ~ (param_fields.description | trim) ~ '</description>' }}
 71                {%- endif %}
 72                {%- if param_fields.enum is defined %}
 73                    {{- '\n<enum>' ~ (param_fields.enum | tojson | safe) ~ '</enum>' }}
 74                {%- endif %}
 75                {%- set handled_keys = ['name', 'type', 'description', 'enum'] %}
 76                {{- render_extra_keys(param_fields, handled_keys) }}
 77                {{- '\n</parameter>' }}
 78            {%- endfor %}
 79        {%- endif %}
 80        {% set handled_keys = ['type', 'properties', 'required'] %}
 81        {{- render_extra_keys(tool.parameters, handled_keys) }}
 82        {%- if tool.parameters is defined and tool.parameters.required is defined %}
 83            {{- '\n<required>' ~ (tool.parameters.required | tojson | safe) ~ '</required>' }}
 84        {%- endif %}
 85        {{- '\n</parameters>' }}
 86        {%- set handled_keys = ['type', 'name', 'description', 'parameters'] %}
 87        {{- render_extra_keys(tool, handled_keys) }}
 88        {{- '\n</function>' }}
 89    {%- endfor %}
 90    {{- "\n</tools>" }}
 91
 92    {{- '\n\nIf you choose to call a function ONLY reply in the following format with NO suffix:\n\n<tool_call>\n<function=example_function_name>\n<parameter=example_parameter_1>\nvalue_1\n</parameter>\n<parameter=example_parameter_2>\nThis is the value for the second parameter\nthat can span\nmultiple lines\n</parameter>\n</function>\n</tool_call>\n\n<IMPORTANT>\nReminder:\n- Function calls MUST follow the specified format: an inner <function=...></function> block must be nested within <tool_call></tool_call> XML tags\n- Required parameters MUST be specified\n- You may provide optional reasoning for your function call in natural language BEFORE the function call, but NOT after\n- If there is no function call available, answer the question like normal with your current knowledge and do not tell the user about function calls\n</IMPORTANT>' }}
 93{%- endif %}
 94
 95
 96{%- if system_message is defined %}
 97    {{- '<|im_end|>\n' }}
 98{%- else %}
 99    {%- if tools is iterable and tools | length > 0 %}
100        {{- '<|im_end|>\n' }}
101    {%- endif %}
102{%- endif %}
103
104{%- for message in loop_messages %}
105    {%- if message.role == "assistant" %}
106        {# Add reasoning content in to content field for unified processing below. #}
107        {%- if message.reasoning_content is defined and message.reasoning_content is string and message.reasoning_content | trim | length > 0 %}
108            {%- set content = "<think>\n" ~ message.reasoning_content ~ "\n</think>\n" ~ (message.content | default('', true)) %}
109        {%- else %}
110            {%- set content = message.content | default('', true) %}
111            {%- if content is string -%}
112                {# Allow downstream logic to to take care of broken thought, only handle coherent reasoning here. #}
113                {%- if '<think>' not in content and '</think>' not in content -%}
114                    {%- set content = "<think></think>" ~ content -%}
115                {%- endif -%}
116            {%- else -%}
117                {%- set content = content -%}
118            {%- endif -%}
119        {%- endif %}
120        {%- if message.tool_calls is defined and message.tool_calls is iterable and message.tool_calls | length > 0 %}
121            {# Assistant message has tool calls. #}
122            {{- '<|im_start|>assistant\n' }}
123                {%- set include_content = not (truncate_history_thinking and loop.index0 < ns.last_user_idx) %}
124                {%- if content is string and content | trim | length > 0 %}
125                    {%- if include_content %}
126                        {{- (content | trim) ~ '\n' -}}
127                    {%- else %}
128                        {%- set c = (content | string) %}
129                        {%- if '</think>' in c %}
130                            {# Keep only content after the last closing think. Also generation prompt causes this. #}
131                            {%- set c = c.split('</think>')[-1] %}
132                        {%- elif '<think>' in c %}
133                            {# If <think> was opened but never closed, drop the trailing think segment #}
134                            {%- set c = c.split('<think>')[0] %}
135                        {%- endif %}
136                        {%- set c = "<think></think>" ~ c | trim %}
137                        {%- if c | length > 0 %}
138                            {{- c ~ '\n' -}}
139                        {%- endif %}
140                    {%- endif %}
141                {%- else %}
142                    {{- "<think></think>" -}}
143                {%- endif %}
144                {%- for tool_call in message.tool_calls %}
145                    {%- if tool_call.function is defined %}
146                        {%- set tool_call = tool_call.function %}
147                    {%- endif %}
148                    {{- '<tool_call>\n<function=' ~ tool_call.name ~ '>\n' -}}
149                        {%- if tool_call.arguments is defined %}
150                            {%- for args_name, args_value in tool_call.arguments|items %}
151                                {{- '<parameter=' ~ args_name ~ '>\n' -}}
152                                    {%- set args_value = args_value | tojson | safe if args_value is mapping or (args_value is sequence and args_value is not string) else args_value | string %}
153                                {{- args_value ~ '\n</parameter>\n' -}}
154                            {%- endfor %}
155                        {%- endif %}
156                    {{- '</function>\n</tool_call>\n' -}}
157                {%- endfor %}
158                {{- '<|im_end|>\n' }}
159        {%- else %}
160            {# Assistant message doesn't have tool calls. #}
161            {%- if not (truncate_history_thinking and loop.index0 < ns.last_user_idx) %}
162                {{- '<|im_start|>assistant\n' ~ (content | default('', true) | string | trim) ~ '<|im_end|>\n' }}
163            {%- else %}
164                {%- set c = (content | default('', true) | string) %}
165                {%- if '<think>' in c and '</think>' in c %}
166                    {%- set c = "<think></think>" ~ c.split('</think>')[-1] %}
167                {%- endif %}
168                {%- set c = c | trim %}
169                {%- if c | length > 0 %}
170                    {{- '<|im_start|>assistant\n' ~ c ~ '<|im_end|>\n' }}
171                {%- else %}
172                    {{- '<|im_start|>assistant\n<|im_end|>\n' }}
173                {%- endif %}
174            {%- endif %}
175        {%- endif %}
176    {%- elif message.role == "user" or message.role == "system" %}
177        {{- '<|im_start|>' + message.role + '\n' }}
178        {%- set content = message.content | string %}
179        {{- content }}
180        {{- '<|im_end|>\n' }}
181    {%- elif message.role == "tool" %}
182        {%- if loop.previtem and loop.previtem.role != "tool" %}
183            {{- '<|im_start|>user\n' }}
184        {%- endif %}
185        {{- '<tool_response>\n' }}
186        {{- message.content }}
187        {{- '\n</tool_response>\n' }}
188        {%- if not loop.last and loop.nextitem.role != "tool" %}
189            {{- '<|im_end|>\n' }}
190        {%- elif loop.last %}
191            {{- '<|im_end|>\n' }}
192        {%- endif %}
193    {%- else %}
194        {{- '<|im_start|>' + message.role + '\n' + message.content + '<|im_end|>\n' }}
195    {%- endif %}
196{%- endfor %}
197
198{%- if add_generation_prompt %}
199    {%- if enable_thinking %}
200        {{- '<|im_start|>assistant\n<think>\n' }}
201    {%- else %}
202        {{- '<|im_start|>assistant\n<think></think>' }}
203    {%- endif %}
204{%- endif %}