Package dev.langchain4j.service

Annotation Interface SystemMessage

@Target({TYPE,METHOD}) @Retention(RUNTIME) public @interface SystemMessage
Specifies either a complete system message (prompt) or a system message template to be used each time an AI service is invoked.
An example: 
 interface Assistant {

     @SystemMessage("You are a helpful assistant")
     String chat(String userMessage);
 }
The system message can contain template variables, which will be resolved with values from method parameters annotated with @V.
An example: 
 interface Assistant {

     @SystemMessage("You are a {{characteristic}} assistant")
     String chat(@UserMessage String userMessage, @V("characteristic") String characteristic);
 }
When both @SystemMessage and AiServices.systemMessageProvider(Function) are configured, @SystemMessage takes precedence.
See Also:

  • Optional Element Summary

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    String
    delimiter
     
    String
    fromResource
    The resource from which to read the prompt template.
    String[]
    value
    Prompt template can be defined in one line or multiple lines.

  • Element Details

    • value

      String[] value
      Prompt template can be defined in one line or multiple lines. If the template is defined in multiple lines, the lines will be joined with a delimiter defined below.
      Default:
      {""}

    • delimiter

      String delimiter
      Default:
      "\n"

    • fromResource

      String fromResource
      The resource from which to read the prompt template. If no resource is specified, the prompt template is taken from value(). If the resource is not found, an IllegalConfigurationException is thrown.

      The resource will be read by calling Class.getResourceAsStream(String) on the AI Service class (interface).

      Default:
      ""