Create Agent

Detailed reference for building custom Copilot agents in TTA.dev. For atomic rules (naming, frontmatter, registration), see the agents instruction.

When to Use This Skill

• Creating a new .agent.md file from scratch
• Adding handoffs between agents for workflow transitions
• Setting up sub-agent orchestration (multi-step pipelines)
• Configuring tool access and MCP server integration
• Designing agent prompt structure with dynamic variables

Prerequisites

• Understand the composition model
• Know which skills and workflows your agent needs (check .github/copilot-catalog.yml)
• Have the target agent's role and responsibilities defined

Quick Start

1. Create .github/agents/my-agent.agent.md with frontmatter
2. Write the body following the Role → Responsibilities → Constraints pattern
3. Add entry to .github/copilot-catalog.yml with skill_refs and workflow_refs
4. Validate: uv run python scripts/validate-catalog.py

Reference Docs

• Handoffs and Orchestration — workflow transitions, sub-agent patterns
• Tool Configuration — aliases, MCP namespaces, strategies
• Prompt Patterns — variables, body structure, best practices