Repository: huggingface/transformers
Pull request: gpt_oss last chat template changes

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Fixes # (issue)


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Models:

- text models: @ArthurZucker
- vision models: @amyeroberts, @qubvel
- speech models: @eustlb
- graph models: @clefourrier

Library:

- flax: @gante and @Rocketknight1
- generate: @zucchini-nlp (visual-language models) or @gante (all others)
- pipelines: @Rocketknight1
- tensorflow: @gante and @Rocketknight1
- tokenizers: @ArthurZucker
- trainer: @zach-huggingface, @SunMarc and @qgallouedec
- chat templates: @Rocketknight1

Integrations:

- deepspeed: HF Trainer/Accelerate: @SunMarc @zach-huggingface
- ray/raytune: @richardliaw, @amogkam
- Big Model Inference: @SunMarc
- quantization (bitsandbytes, autogpt): @SunMarc @MekkCyber

Documentation: @stevhliu

HF projects:

- accelerate: [different repo](https://github.com/huggingface/accelerate)
- datasets: [different repo](https://github.com/huggingface/datasets)
- diffusers: [different repo](https://github.com/huggingface/diffusers)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

Maintained examples (not research project or legacy):

- Flax: @Rocketknight1
- PyTorch: See Models above and tag the person corresponding to the modality of the example.
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Changed files:
filename: src/transformers/models/gpt_oss/convert_gpt_oss_weights_to_hf.py
patch: @@ -561,7 +561,7 @@ def write_tokenizer(tokenizer_path: str, save_dir: str, instruct: bool = False):
                 {%- if not loop.last %}
                     {{- ",\n" }}
                 {%- else %}
-                    {{- "\n" }}
+                    {{- ",\n" }}
                 {%- endif -%}
             {%- endfor %}
             {{- "}) => any;\n\n" }}
@@ -696,6 +696,15 @@ def write_tokenizer(tokenizer_path: str, save_dir: str, instruct: bool = False):
             {%- endif %}
         {%- endif %}
         {%- if "tool_calls" in message %}
+            {#- We need very careful handling here - we want to drop the tool call analysis message if the model #}
+            {#- has output a later 
 message, but otherwise we want to retain it. This is the only case #}
+            {#- when we render CoT/analysis messages in inference. #}
+            {%- set future_final_message = namespace(found=false) %}
+            {%- for future_message in loop_messages[loop.index:] %}
+                {%- if future_message.role == 'assistant' and "tool_calls" not in future_message %}
+                    {%- set future_final_message.found = true %}
+                {%- endif %}
+            {%- endfor %}
             {#- We assume max 1 tool call per message, and so we infer the tool call name #}
             {#- in "tool" messages from the most recent assistant tool call name #}
             {%- set tool_call = message.tool_calls[0] %}
@@ -704,9 +713,9 @@ def write_tokenizer(tokenizer_path: str, save_dir: str, instruct: bool = False):
             {%- endif %}
             {%- if message.content and message.thinking %}
                 {{- raise_exception("Cannot pass both content and thinking in an assistant message with tool calls! Put the analysis message in one or the other, but not both.") }}
-            {%- elif message.content %}
+            {%- elif message.content and not future_final_message.found %}
                 {{- "
assistant
analysis
" + message.content + "
" }}
-            {%- elif message.thinking %}
+            {%- elif message.thinking and not future_final_message.found %}
                 {{- "
assistant
analysis
" + message.thinking + "
" }}
             {%- endif %}
             {{- "
assistant to=" }}