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name: prompt-creator description: Guide for creating effective system prompts for AI agents and assistants. Use when writing, reviewing, or improving system prompts, agent instructions, or assistant configurations.

Prompt Creator

Guidelines for designing effective system prompts for AI agents and assistants.

Core Principles

Start Simple, Iterate

Begin with minimal instructions and add complexity only as needed. Prompt design is iterative—test with real inputs and refine based on results.

For complex agent behaviors, break the task into simpler subtasks first. Build up gradually rather than front-loading complexity.

Use Clear Instructions

Structure prompts with explicit commands: "Write", "Classify", "Summarize", "Translate", "Extract", "Analyze".

Place instructions at the beginning. Use separators to distinguish sections:

### Instructions ###
[Core behavior and responsibilities]

### Context ###
[Domain knowledge and constraints]

### Output Format ###
[Expected response structure]

Be Specific and Direct

Vague:

Keep responses short and helpful.

Specific:

Respond in 2-3 sentences. Include one actionable recommendation.

The more descriptive and detailed the prompt, the better the results. Include:

• Exact output formats
• Specific constraints
• Concrete examples of desired behavior

Say What To Do, Not What Not To Do

Weak (focuses on prohibitions):

DO NOT ask for personal information.
DO NOT make assumptions.
DO NOT provide medical advice.

Strong (focuses on actions):

Recommend from the top 10 trending items.
Ask clarifying questions before proceeding.
Direct health questions to qualified professionals.

Positive instructions are more effective than negative constraints.

Provide Examples for Desired Formats

When a specific output structure is needed, show it:

Extract entities from the input text.

Desired format:
- People: <comma_separated_list>
- Places: <comma_separated_list>
- Organizations: <comma_separated_list>

Example input: "Dr. Sarah Chen presented findings at MIT yesterday."
Example output:
- People: Dr. Sarah Chen
- Places: MIT
- Organizations: MIT

Balance Detail with Relevance

Include only details that contribute to the task. Unnecessary context dilutes the signal.

Ask: "Does this information change how the agent should behave?" If not, remove it.

System Prompt Structure

Effective system prompts typically follow this order:

1. Role/Identity - Who the agent is
2. Core Responsibilities - Primary tasks and behaviors
3. Constraints - Boundaries and limitations
4. Output Format - How to structure responses
5. Examples - Concrete demonstrations (if needed)

You are a [role] that [primary function].

## Responsibilities
- [Responsibility 1]
- [Responsibility 2]

## Constraints
- [Constraint 1]
- [Constraint 2]

## Response Format
[Structure specification]

Common Pitfalls

| Pitfall | Problem | Solution | |---------|---------|----------| | Vague quantities | "a few", "short", "brief" | Use exact numbers: "2-3 sentences" | | Double negatives | "don't avoid" | Use positive framing | | Contradictory rules | "be concise" + "be thorough" | Prioritize or scope each rule | | Missing edge cases | Undefined behavior | Add fallback instructions | | Excessive length | Context dilution | Remove non-essential content |