# Phauks Grimbound Prompt Engineering > Prompt Engineering for Claude Agents - Skill: `tomevault-io/phauks-grimbound-prompt-engineering` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/phauks-grimbound-prompt-engineering` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/phauks-grimbound-prompt-engineering/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - 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/phauks-grimbound-prompt-engineering --- # Prompt Engineering for Claude Agents ## The Three Laws of Agent Prompts ### 1. Right Altitude (Goldilocks Zone) | Level | Example | Problem | |-------|---------|---------| | **Too Low** | "If file is .ts AND has 'async' AND line > 100..." | Brittle, breaks on edge cases | | **Just Right** | "Review TypeScript async patterns for common pitfalls" | Clear, flexible, actionable | | **Too High** | "Be a good code reviewer" | Vague, inconsistent results | **Test**: Can you imagine 3 different valid interpretations? Too high. Can you imagine it breaking on a valid input? Too low. ### 2. Few-Shot Examples (3-5 Canonical Cases) Don't list every possibility. Show representative examples: ```markdown ## Examples ### Example 1: Clear Success Case Input: [Typical, well-formed input] Output: [Expected response with reasoning shown] ### Example 2: Edge Case Input: [Unusual but valid input] Output: [How to handle gracefully] ### Example 3: What NOT to Do Input: [Tricky input that could mislead] Output: [Why the naive approach is wrong, correct approach] ``` ### 3. Explicit Constraints Tell Claude what NOT to do: ```markdown ## Constraints - Do NOT modify files outside the specified directory - Do NOT commit changes without confirmation - NEVER include secrets in outputs - ALWAYS validate input before processing ``` ## Prompt Structure Template ```markdown # [Agent/Skill Name] [One-sentence purpose] ## Context [Background information Claude needs] ## Responsibilities 1. **[Verb] [Object]**: [Brief description] 2. **[Verb] [Object]**: [Brief description] ## Workflow When given [input type]: 1. [First action] 2. [Second action] 3. [Third action] ## Examples ### Example 1: [Scenario Name] **Input**: [Sample] **Output**: [Expected result] **Reasoning**: [Why this is correct] ### Example 2: [Edge Case] **Input**: [Tricky sample] **Output**: [Correct handling] **Reasoning**: [Common mistake avoided] ## Anti-Patterns - **Don't**: [Bad practice] **Instead**: [Good practice] ## Output Format [Specify exact format if needed: JSON, markdown, etc.] ``` ## Context Engineering ### Tell Claude About Session State ```markdown ## Session Context - Context may be compacted between turns - Important decisions will be saved to CLAUDE.md - You may need to resume work from a previous session - Use episodic memory to recall past decisions ``` ### Memory Management Hints ```markdown ## Memory Usage When working on large tasks: 1. Save progress incrementally to files 2. Document key decisions in CLAUDE.md 3. Use clear commit messages for future reference 4. Create TODO items for incomplete work ``` ## Model-Specific Considerations ### Haiku (Fast, Cheap) - Keep prompts concise - Use for simple, well-defined tasks - Avoid requiring complex reasoning chains ### Sonnet (Balanced) - Standard detail level - Good for most agent tasks - Can handle moderate complexity ### Opus (Maximum Capability) - Worth extra context for complex tasks - Best for nuanced decisions - Use for critical, high-stakes work ## Prompt Optimization Techniques ### 1. Front-Load Critical Information ```markdown ## CRITICAL: [Most important instruction] [Less critical context below] ``` ### 2. Use Structured Sections ```markdown ## Input Format [What Claude receives] ## Output Format [What Claude must produce] ## Processing Rules [How to transform input to output] ``` ### 3. Provide Escape Hatches ```markdown If you encounter a situation not covered by these instructions: 1. State what you're uncertain about 2. Explain your best judgment 3. Ask for clarification if needed ``` ### 4. Include Verification Steps ```markdown Before completing: - [ ] Verify output matches expected format - [ ] Check for security concerns - [ ] Ensure changes are minimal and focused ``` ## Common Mistakes ### Mistake 1: Overly Prescriptive ```markdown # BAD If the error contains "undefined" and the file is JavaScript: Check for null pointer Else if the error contains "type" and the file is TypeScript: Check for type mismatch ... # GOOD Diagnose errors by: 1. Reading the error message carefully 2. Identifying the error category (type, null, async, etc.) 3. Locating the source in the codebase 4. Understanding the root cause before fixing ``` ### Mistake 2: No Examples ```markdown # BAD Review code for quality issues. # GOOD Review code for quality issues. Example issue types: - Unused variables (remove them) - Complex conditions (extract to named functions) - Missing error handling (add try/catch or validation) ``` ### Mistake 3: Conflicting Instructions ```markdown # BAD Be thorough and check everything. Also be fast and efficient. # GOOD Prioritize checks: 1. Critical: Security vulnerabilities (always check) 2. Important: Logic errors (check if time allows) 3. Nice-to-have: Style issues (skip if time-constrained) ``` ## Testing Your Prompts ### Adversarial Testing Try inputs designed to break the prompt: - Empty input - Malformed input - Edge cases - Unexpected formats ### A/B Testing Compare prompt variations: 1. Run both on same inputs 2. Evaluate which produces better results 3. Iterate on winner ### User Feedback Loop 1. Deploy prompt 2. Collect failure cases 3. Add examples for failures 4. Repeat --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/phauks) — claim your Tome and manage your conversions.