Why the system prompt is so critical
The system prompt is the contract between you and the LLM. It defines who the AI is, what it does, how it responds, and what it never does.
The 10 techniques
Precise persona (not generic)
Bad: 'You are a helpful assistant.' Good: 'You are Maya, a data consultant at DataSAI with 8 years of data science experience. You talk to non-technical executives and give concise answers with concrete examples.'
Explicit negative constraints
List what the AI must never do. Negative constraints drastically reduce unexpected behaviours.
Structured output format
Specify exactly the expected format. Consistency of format reduces post-processing.
Few-shot examples in the system
Include 2-3 good exchange examples directly in the system prompt. The LLM will imitate the tone and structure far more faithfully than abstract instructions.
Advanced technique: also include an example where the AI correctly refuses an out-of-scope request. Counter-examples are as important as positive ones.
Explicit uncertainty handling
Instruct the AI on what to do when it does not know. Reduces hallucinations by 40-60%.
Techniques 6-10
Memory management, human escalation triggers, multilingualism handling, prompt versioning and systematic A/B testing.
These system-prompt techniques are applied to agents and assistants throughout the AI Engineering Bootcamp.
