output_parser=JSONListOutputParser(),
        template=dedent(
            """
                You are an intelligent agent that is generating thoughts in a tree of
                thoughts setting.
                
                The output should be a markdown code snippet formatted as a JSON list of
                strings, including the leading and trailing "```json" and "```":
                
                ```json
                [
                "<thought-1>",
                "<thought-2>",
                "<thought-3>"
                ]
                ```
                
                PROBLEM
                
                {{ problem_description }}
                
                {% if thoughts %}
                VALID THOUGHTS
                
                {% for thought in thoughts %}
                {{ thought }}
                {% endfor %}
                
                Possible next {{ n }} valid thoughts based on the last valid thought:
                {% else %}
                
                Possible next {{ n }} valid thoughts based on the PROBLEM:
                {%- endif -%}
                """
        ).strip(),
    )
[docs]class CheckerOutputParser(BaseOutputParser):
[docs]    def parse(self, text: str) -> ThoughtValidity:
        """Parse the output of the language model."""
        text = text.upper()
        if "INVALID" in text:
            return ThoughtValidity.INVALID
        elif "INTERMEDIATE" in text:
            return ThoughtValidity.VALID_INTERMEDIATE
        elif "VALID" in text:
            return ThoughtValidity.VALID_FINAL
        else:
            return ThoughtValidity.INVALID
    @property
    def _type(self) -> str:
        return "tot_llm_checker_output"
CHECKER_PROMPT = PromptTemplate(
    input_variables=["problem_description", "thoughts"],
    template=dedent(
        """