Hanzo Dev · Coding agent

Describe the change.
Dev ships it.

Hanzo Dev is a coding agent. It reads your repository, makes the change, runs the tests and shows you the diff — in your terminal, on the web, in the cloud and in Slack.

Open Dev Install

Read the docs →

terminal

curl -fsSL https://hanzo.sh | sh

dev

a session in this repository

dev exec "fix the failing test"

the same task, run to the end without the interface

dev cloud exec "add rate limiting"

handed to Hanzo’s cloud; dev cloud apply brings the diff back

One agent

Wherever the work is.

The same agent, the same models and the same account in every place it runs.

Terminal

devIn any repository. It reads the code, makes the change and runs commands in a sandbox. Bare hanzo opens the same session.

Web

hanzo.ai/devDescribe an app. Dev writes it, runs it and deploys it, with the database, the sign-in and the storage already there.

Cloud

dev cloud execHand a task to Hanzo’s cloud and close the laptop. dev cloud diff shows what it did; dev cloud apply puts it in your checkout.

Slack

An org admin connects the workspace in Dev’s settings, and the team talks to it from their channels.

Open Dev on the web →

Install

One line, three ways.

Linux, macOS and Windows. Dev updates itself the way it was installed.

hanzo.sh

curl -fsSL https://hanzo.sh | sh

Linux and macOS. One native binary, its checksum verified.

npm

npm install -g @hanzo/dev

Every platform, Windows included.

Homebrew

brew install hanzoai/tap/hanzo-dev

macOS and Linux.

Then sign in. Hanzo IAM links the machine to your account.

bash

dev login                 # pick an account: Hanzo is the default
dev login --hanzo         # straight to your Hanzo account
dev login --with-api-key  # or paste a Hanzo API key, hidden

Getting started →

Models

Enso by default. Any model by name.

Dev starts on enso-auto through api.hanzo.ai, so every call is metered on your Hanzo account. Every model Hanzo serves is a flag or a /model away.

bash

dev                         # enso-auto, through api.hanzo.ai
dev --model enso-ultra      # name any model Hanzo serves
/model zen5-coder           # or switch inside a session

Enso →Every model →

Controller

Kai decides. Dev does.

Kai is Dev’s own controller, not an adviser. At each step it returns an operation Dev can run, or says plainly that it abstains. The cheapest step that holds is the one taken.

An action appliesOne candidate, its preconditions hold: it runs, and no model is asked.

Kai decidesWhere to fix, what to do and how hard to try, asked of Kai in one structured call.

Generate, low effortA model writes the edit, asked for as a strict schema.

Generate, full effortThe same, given room to reason.

RecoverA failure seen before with nothing changed picks a different action, or escalates. It never replays the loop.

Kai, the decision model →

Proof

Built to be checked.

Nothing counts as done because a model said so.

Verified, not predicted

A step is settled by what the verifier records — the exit status, the tests, the diff — never by what anything expected.

Bound to the revision

Preconditions are checked just before an action runs, and an edit voids every decision made against the files as they were.

A ledger you can replay

Every decision, fallback, run and verification is a line with a stable id and its reason, credentials redacted, so its time and cost can be read back.

Sandbox

Inside the fence you set.

Commands run in a sandbox and are approved inside it. Ask before every action, or lift the fence for one run. A repository’s own tool servers stay off until you say you trust it.

bash

hanzo dev --ask           # ask before each action
hanzo dev --no-sandbox    # run unconfined, for this run only
hanzo dev --project-mcp   # also load this repository's .mcp.json

Gen

Dev is our agent. Gen runs any agent.

Hanzo Gen is the harness: Claude Code, Codex, Cursor and the rest, on Hanzo’s tools and models and linked to your account. Dev is the agent it opens when none is named.

Hanzo Gen →

Open source

Read every line.

Dev is Apache-2.0 on GitHub. Build it, change it, send a pull request — hanzoai/dev.

The source →Releases →

Questions

Asked plainly.

What does it cost?

Dev is free and open source. Its model calls go through api.hanzo.ai and are metered on your Hanzo account at the price list’s rates, so one account and one bill cover every model.

Which systems does it run on?

Linux, macOS and Windows. hanzo.sh installs it on Linux and macOS, npm everywhere, Homebrew on macOS and Linux.

How does it update?

The way it was installed: from its own release, from npm, or from Homebrew.

Can I bring a key instead of signing in?

Yes. dev login --with-api-key takes a Hanzo API key, hidden as it is typed or read from piped stdin.

How is Dev different from Gen?

Dev is Hanzo’s coding agent. Gen is the harness that runs any coding agent, Dev included, on Hanzo’s tools and models.

Read

The agent, its controller, its source.

Where to start, what Dev thinks with, and the code.