# `Transmuter.ChatTemplate`
[🔗](https://github.com/georgeguimaraes/transmuter/blob/v2.0.0/lib/transmuter/chat_template.ex#L1)

Renders the chat template of a model repository, like `apply_chat_template` in Python transformers.

Needs the optional `otera` dependency, which renders Jinja templates in pure Elixir.

    repo = Transmuter.Repo.load!({:hf, "HuggingFaceTB/SmolLM2-135M-Instruct"})
    Transmuter.ChatTemplate.render(repo, [%{role: "user", content: "Hello"}])
    #=> "<|im_start|>system\nYou are a helpful AI assistant named SmolLM...<|im_start|>assistant\n"

Map keys can be atoms or strings. A plain Elixir map gives its keys to `tojson` in alphabetical order. To get the key order of transformers for tool definitions or messages that come from JSON, decode the JSON with `Otera.JSON.decode!/1`.

# `render`

Renders `messages`, a list of maps with `:role` and `:content`, with the chat template of `repo`.

## Options

  * `:continue_final_message` - ends the prompt inside the final message, so that the model continues it. The default is `false`.

  * `:add_generation_prompt` - ends the prompt with the start of an assistant message. The default is `true`, or `false` with `:continue_final_message`.

  * `:tools` - a list of tool definitions in JSON schema form. A repository with a template named `"tool_use"` renders tools with it.

  * `:template_options` - other variables of the template, such as `enable_thinking: false` for Qwen3.

  * `:template` - the template to render in place of that of the tokenizer, such as the `:processor_chat_template` of `Transmuter.Repo`.

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*Consult [api-reference.md](api-reference.md) for complete listing*