Introduction

Welcome to GitCosmo — the open hub for AI agent builders.

GitCosmo is a practical reference for building with AI agents: setting them up, giving them capabilities, and tuning them until they're genuinely useful. Everything works with Claude Code, Codex CLI, Gemini CLI, Cursor, Grok Build, and any other agent that can read markdown and call tools.

Find what you need

I want to…Go to
Set up my first coding agentGetting Started
Understand what agents actually areWhat are AI Agents?
Give my agent new capabilitiesUnderstanding MCP + the MCP directory
Make my agent follow my project's rulesAGENTS.md Best Practices
Write reusable instructions that actually workWriting Great Skills + the Skills directory
Build a repeatable end-to-end workflowBuilding Your First Workflow
Coordinate multiple agentsMulti-Agent Patterns
Fix an agent that's misbehavingTuning & Troubleshooting
Copy working configs and templatesExamples

How the pieces fit together

Four things determine how well an agent performs, in rough order of impact:

  1. The model — pick a strong one; everything else amplifies or wastes it.
  2. Context — what the agent knows about your project. AGENTS.md is the highest-leverage file you can write.
  3. Tools — what the agent can do. MCP servers add filesystem, browser, search, database, and service access.
  4. Process — plans, self-review, and handoffs. Skills and workflows encode process so you don't re-explain it every session.

Most "my agent is dumb" problems are actually context or process problems. The docs here focus on those two, because that's where you have the most control.

Philosophy

We believe the future of software is built by people directing teams of specialized agents. GitCosmo exists to raise the quality bar for the building blocks — the skills, configs, and patterns — that make those agents reliable.

Everything is open. Everything is designed to be copied and improved.