Agent skill · product strategy · anthropics
agent-development
This skill should be used when the user asks to "create an agent", "add an agent", "write a subagent", "agent frontmatter", "when to use description", "agent examples", "agent tools", "agent colors", "autonomous agent", or needs guidance on agent structure, system prompts, triggering conditions, or agent development best practices for Claude Code plugins.
Why this skill is useful
Provides detailed guidelines and best practices for creating agents in Claude Code plugins, which the AI wouldn't reliably generate on its own.
What it needs
About 6k tokens when loaded. Last updated 2026-08-07. 33,212 stars on the source repository.
What this skill does
Agent Development for Claude Code Plugins Overview Agents are autonomous subprocesses that handle complex, multi-step tasks independently. Understanding agent structure, triggering conditions, and system prompt design enables creating powerful autonomous capabilities. Key concepts: Agents are FOR autonomous work, commands are FOR user-initiated actions Markdown file format with YAML frontmatter Triggering via description field with examples System prompt defines agent behavior Model and color customization Agent File Structure Complete Format Frontmatter Fields name (required) Agent identifier used for namespacing and invocation. Format: lowercase, numbers, hyphens only Length: 3-50 characters Pattern: Must start and end with alphanumeric Good examples: code-reviewer test-generator api-docs-writer security-analyzer Bad examples: helper (too generic) -agent- (starts/ends with hyphen) myagent (underscores not allowed) ag (too short, < 3 chars) description (required) Defines when Claude should trigger this agent. This is the most critical field — it is loaded into context whenever the agent is registered, so the harness can decide when to dispatch. Must include: 1. Triggering conditions ("Use this agent when...") 2. A short prose summary of the typical trigger scenarios 3. A pointer to a "When to invoke" section in the agent body for the detailed worked scenarios Format: Best practices: Name 2-4 trigger scenarios in the prose summary Cover both proactive (assistant invokes itself) and reactive (user requests) triggering Cover different phrasings of the same intent Be specific about when NOT to use the agent Put detailed scenarios in the body under "When to invoke" as a bullet list of prose descriptions model (required) Which model the agent should use. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills anthropics/agent-development--29c12a