terminal · ai · agent

Tell it what to build.
It builds it.

harness is an AI coding agent that reads, writes and edits your files and runs commands to finish real tasks — right in your terminal.

$ npm i -g harness-terminal
or run it once → npx harness-terminal
what it does

An agent that works where you do.

Not a chat box that hands you snippets. harness acts in your project — files, shell, tests — and keeps you in control.

→ ✓

Works in your repo

Reads, writes and edits files and runs commands across your project to actually finish the task.

Asks before risky moves

Destructive commands like rm pause for your Y/N approval. Nothing dangerous runs behind your back.

/model

Switch models live

Pick your model from inside the agent. Starts on Gemini flash — fast and cheap.

/login

Bring your own key

Your Gemini key, stored locally on your machine. You pay your own usage — no middleman.

❯ _

Chat or one-shot

Work interactively in the TUI, or fire a single headless task from any script.

Safe by default

Guardrails are on out of the box. You stay the one who decides what actually happens.

get going

Running in under a minute.

1install

Add it globally

One command and the harness command is yours.

npm i -g harness-terminal
2connect

Paste your key

Run it and drop in your Gemini key — grab a free one at aistudio.google.com.

harness
3build

Just ask

Type a task in plain English. harness explores, edits, runs and verifies.

❯ add tests for utils.ts