"system_prompt is not supported for CondenseQuestionChatEngine"

[sad-mathematician]

Does this mean that we cannot set an external system prompt with this Chat Engine? Meaning if we wanted the response in formatted HTML for example, can we not set this instruction? The condense_question_prompt doesn't seem to be the system prompt that could achieve this.

[dosubot[bot]]

Yes, the error message "system_prompt is not supported for CondenseQuestionChatEngine" means that you cannot set an external system prompt with this Chat Engine.

To set instructions for the response to be in formatted HTML, you can modify the condense_question_prompt to include instructions for HTML formatting. Here is an example of how you can do this:

from llama_index.legacy.prompts.base import PromptTemplate

HTML_TEMPLATE = """\
Given a conversation (between Human and Assistant) and a follow up message from Human, \
rewrite the message to be a standalone question that captures all relevant context \
from the conversation. The response should be formatted in HTML.

<Chat History>
{chat_history}

<Follow Up Message>
{question}

<Standalone question in HTML>
"""

html_prompt = PromptTemplate(HTML_TEMPLATE)

# Initialize the CondensePlusContextChatEngine with the custom HTML prompt
chat_engine = CondensePlusContextChatEngine.from_defaults(
    retriever=retriever,
    llm=llm,
    memory=memory,
    condense_prompt=html_prompt,
    # other parameters...
)

This way, the CondensePlusContextChatEngine will use the html_prompt which includes instructions to format the response in HTML ^[1][2][3].

To continue talking to Dosu, mention @dosu.

[sad-mathematician]

adding a prompt to the condense_question_prompt only uses the prompt while creating a condensed question and doesn't use that prompt while generation of the final answer.