Where do you start if you want to build your first AI agent?

Start from a task, not a framework. Pick one small, repeatable job you already do by hand, such as sorting emails, pulling numbers from a site or drafting a weekly report, and write down the steps you take. Those steps tell you which tools the agent will need.

At its core an agent is a loop: a model reads the goal, chooses a tool, sees the result and decides what to do next until it is done. You can build that with any major model API and two or three tools in an afternoon. Doing it once by hand teaches you more than starting inside a large framework that hides the loop.

Keep the first version to a single agent with a few tools and a step limit. Multi-agent setups, memory and planners are worth adding only after you can see, in real runs, where the single agent falls short.

Once it works, the next skill is giving it good tools. Wrapping an API you use as an MCP server lets the same tool work in Claude, ChatGPT and code editors, so the effort carries over to whatever you build next.

Listings mentioned

• Agent workflow designer · skill by alirezarezvani
  Walks through choosing between a single agent and a multi-agent pipeline, a useful check before adding complexity.
• MCP builder · skill by anthropics
  A step-by-step guide to building an MCP server, the usual way to give a new agent its first real tools.

Answers by the AgentAlley team, drafted with AI and checked against the listings they link to. Not a real-person reply from the original thread.