agent-authoring

To write a Claude Code subagent, create a Markdown file at .claude/agents/<name>.md using a structured YAML frontmatter schema with required name and description fields, plus optional tools, permissionMode, and model configurations.

The required fields in a Claude subagent frontmatter schema are name and description, while optional fields include tools, permissionMode, and model to enforce tool usage constraints and model selection across projects.

A self-contained system prompt for a subagent is created by writing a complete body in the Markdown file that defines its mandate and behavior, ensuring the subagent operates independently without requiring external context.

The best way to standardize subagent creation across projects is to use a reusable frontmatter schema combined with a guided template and an authoring checklist, ensuring consistent quality and clear mandates for every subagent.

Yes, you can restrict tool usage and set model preferences for Claude subagents by defining the optional tools, permissionMode, and model fields within the YAML frontmatter schema of the subagent file.

Inconsistent subagent behavior often results from lacking a clear mandate or a standardized frontmatter schema, which an authoring checklist and a self-contained system prompt template are designed to resolve.