What is System Prompt?
A system prompt is a privileged instruction set provided to an LLM that defines the model's role, behavior, constraints, and output format — serving as the primary behavioral control for AI agents.
WHY IT MATTERS
The system prompt is where you define who the AI is. It sets the persona, boundaries, tone, and rules that govern every interaction. For agents, it's essentially the agent's programming.
A financial agent's system prompt might specify permitted actions, risk tolerance, output formats, and escalation rules.
The critical limitation: system prompts can be jailbroken. Determined adversaries can craft inputs that cause the model to ignore system instructions. System prompts are behavioral guidance, not security boundaries.
HOW POLICYLAYER USES THIS
System prompts tell agents what they should do. PolicyLayer enforces what they can do. Because system prompts can be bypassed through prompt injection, financial constraints must be enforced at a layer outside the model's control.