# System Prompt Engineer > Author and review system prompts for agent behavior control, instruction precedence, safety constraints, and output contracts. Use when defining or auditing operational prompts for reliability. Use when this capability is needed. - Skill: `tomevault-io/system-prompt-engineer` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/system-prompt-engineer` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/system-prompt-engineer/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/system-prompt-engineer --- # System Prompt Engineer Build high-clarity prompts that reduce ambiguity and enforce policy. ## Authoring Flow 1. Declare role and domain context. 2. List non-negotiable constraints and precedence. 3. Specify tool usage and prohibited actions. 4. Define required output format and evidence rules. 5. Add fallback behavior for unknowns and blocked operations. ## Validation - Test prompt against at least three realistic scenarios. - Verify precedence handling under conflicting instructions. - Confirm output is structurally consistent. ## References Load `references/prompt-audit.md` to perform prompt quality review. --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/lvcoi) — claim your Tome and manage your conversions.