Why is the length of the system prompt important?

Shorter, focused prompts (ideally 500-2,000 characters) reduce latency and prevent the model from getting distracted by irrelevant information, leading to more reliable agent behavior.

Does this skill work on multiple files at once?

Yes, it includes a batch audit process that generates a summary table for an entire directory, identifying missing fields and anti-patterns across all agent files.

How does it help with model selection?

The skill provides logic for when to use Claude 3 Opus (complex judgment), Sonnet (formulaic tasks), or Haiku (simple validation) based on the agent's specific domain.

What are agent prompt anti-patterns?

Anti-patterns include listing concepts the model already knows, using redundant 'don't' sections that mirror 'do' sections, and including fictional progress trackers or verbose bullet points without specific guidance.

Agent Modernizer

Name: Agent Modernizer
Author: therealbill

bytherealbill

0•

Developer Tools

Audits and refactors Claude Code agent definitions to ensure concise prompts, proper frontmatter, and adherence to modern plugin standards.

The Agent Modernizer is a specialized tool designed to upgrade and refine Claude Code plugin agent definitions. It systematically audits .md agent files to identify common prompt anti-patterns, such as redundant instructions and 'teaching the model its own knowledge.' By transforming verbose, list-heavy descriptions into opinionated, decision-focused guidance, this skill helps developers create more efficient agents that leverage the model's inherent capabilities while maintaining strict operational boundaries and proper metadata structure.

Key Features

01Comprehensive auditing of agent frontmatter and system prompt quality

02Expert guidance on model selection (Opus, Sonnet, Haiku) and agent merging

030 GitHub stars

04Automated rewriting into concise, decision-driven role statements

05Batch processing capabilities with prioritized finding summaries

06Identification of anti-patterns like redundant lists and fictional content

Use Cases

01Streamlining over-engineered prompts to reduce token usage and improve focus

02Auditing agent directories for missing required fields like color and examples

03Modernizing legacy Claude Code plugins to meet current performance standards

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add therealbill/mynet agent-modernizer

For use in Claude.ai and ChatGPT

Download Skill