How to specify a system prompt with template variables

[rwankar]

I'm trying to specify a system prompt with a template variable. e.g "You are a .... and today's date is {date}"

I tried the following.

        Map systemParams = (a map with "date" -> "Feb 17, 2025");

        return client
            .prompt(userText)
            .advisors(advisorSpec -> {
                advisorSpec
                    // push the advisor that sets the memoryId for all advisors
                    .advisors(new MessageChatMemoryAdvisor(chatMemory))
                    .param(MessageChatMemoryAdvisor.CHAT_MEMORY_CONVERSATION_ID_KEY, memoryId);

                advisorSpec
                    // Add PromptChatMemoryAdvisor with system params
                    .advisors(new PromptChatMemoryAdvisor(chatMemory))
                    .param("system.text", systemPrompt)
                    .param("system.params", systemParams);
            }).call.chatResponse();

I get the error..

java.lang.IllegalStateException: Not all template variables were replaced. Missing variable names are [date]
        at org.springframework.ai.chat.prompt.PromptTemplate.validate(PromptTemplate.java:232) ~[spring-ai-core-1.0.0-SNAPSHOT.jar:1.0.0-SNAPSHOT]

Any ideas on what I'm missing?

[rwankar]

Doing this works..

        PromptTemplate promptTemplate = new PromptTemplate(systemPromptTemplate);
        Prompt systemPrompt = promptTemplate.create(variables);
        String systemMessage = systemPrompt.getContents();

        return client
            .prompt(userText)
            .system(systemMessage)
            ....

May be I'm using the PromptChatMemoryAdvisor incorrectly.