An agent of your own

1. Scaffold the harness

bunx create-routecraft my-agent --example https://github.com/routecraftjs/craft-harness
cd my-agent
bun run setup

setup generates the two secrets that cannot be committed, writes them to .env and writes .routecraft/settings.yaml so the CLI needs no flags. It leaves one value for you:

# in .env
LLM_API_KEY=sk-your-key-here

The harness is a Routecraft project like any other. Chat, a sandboxed shell, web fetch and search, a workspace, memory, a scheduler and human approvals are each an ordinary route under capabilities/, with their guardrails written where you can read and change them. There is no agent framework layer: the platform is Routecraft, and this repository is what a project built on it looks like.

2. Run it, and talk to it from a terminal

bun run dev

In another terminal:

bun run exec chat --session=demo --message="what can you do?"

No --token, no --url: the instance is walled and the settings file carries the credential. The transcript is a file, and --session names which one, so the next message continues the same conversation.

3. Talk to it from your editor

The harness serves the Agent Client Protocol from boot, on a server of its own named editor (the harness gives each surface its own port, as Servers and ports describes), behind the same key as everything else. setup printed the two lines an editor needs:

command:   /path/to/my-agent/node_modules/.bin/craft
arguments: acp --profile editor

Register them in an editor that speaks ACP (Zed, JetBrains), and hold the conversation without leaving it. Through that conversation the agent reads, edits, searches and runs things in the project you have open, using the editor's own files and terminal, through nine capabilities under capabilities/editor/ with their guardrails in the open. Talk from your editor has every editor and what a conversation carries.

craft acp is a pipe and nothing else: it appends /acp to the profile's URL, sends the token and the agent name, and forwards every message. It never starts the harness, which is what lets one editor entry reach your laptop today and a team harness tomorrow by changing a profile.

4. Or from the assistant you already use

The same harness serves MCP at http://localhost:8081/mcp, presenting the same key as a bearer token. Connect Claude, Cursor or Copilot to it with the URL instead of a command, the way Expose to an agent shows, and use the chat-tool tool. Both reach the same conversation.

5. Make it yours

HELP.md in the project lists what every capability does, what it refuses to do until you configure it, and how each is reached. Read it once and delete it. Then:

• Give it a tool. Add a capability folder with an mcp() or direct() source and the agent can be granted it by name in its tools: list.
• Teach it a job. Add a skill under skills/: markdown the agent loads for one kind of work, shipped as a package when another team should have it.
• Let it start on its own. A cron() capability that wakes the agent, with .defer() where it must ask you first.

Project structure shows where agents, skills and capabilities live; Durable agents shows how a conversation survives a restart and a decision that takes days.

6. What comes next

This harness stays yours: a personal agent on your own access. When a capability you built in it has earned its place, promote the capability, not the harness: it moves to the team harness, always on, on service credentials, and every team reaches it through the doors. Local harness, team harness is the step.