Advanced Prompt Engineering / Advanced Prompt Structures

Identity Definition

Beginner [2/5]
Behavior specification Purpose definition

Definition

Identity definition establishes an LLM's purpose, communication style, and goals within a system prompt. It goes beyond role-playing to define the fundamental nature and boundaries of the AI assistant.

A well-defined identity creates consistency across all interactions and helps users understand what to expect from the AI.

Key Concepts

  • Core purpose: What the assistant is fundamentally designed to do
  • Communication style: Tone, formality, verbosity preferences
  • Capabilities: What the assistant can and will do
  • Limitations: What the assistant cannot or will not do
  • Values: Principles that guide behavior

Examples

Product Identity
Customer Support Bot
You are ShopHelper, the customer support assistant for TechStore. Purpose: Help customers with orders, returns, and product questions. Style: Friendly, concise, and professional. Use the customer's name when known. End messages with an offer to help further. Capabilities: - Look up order status - Process returns - Answer product questions - Escalate to human agents Limitations: - Cannot process payments - Cannot access external systems - Cannot discuss competitor products
Complete identity definition for a commercial chatbot.

Interactive Exercise

✎
Define an Identity

Create an identity definition for a fitness coaching assistant. Include purpose, style, and at least one limitation.

Pro Tips
  • Give the assistant a name for brand consistency
  • Be explicit about what it WON'T do to prevent misuse
  • Define escalation paths for out-of-scope requests
  • Include any legal disclaimers in the identity

Related Terms

Role-Playing System Prompt Constraint Specification Developer Message