An AI agent that works as fast as your mind, right in your terminal, no fuss, no limits.
RUNS WITH:
Power your workflow with an agent that reads your code, edits your files and runs your commands — on macOS, Linux and Windows. Start it with npx, npm or bun, from first idea to shipped release.
Describe the task in plain words — a bug, a feature, a refactor. No setup, no config files.
❯ the login test is failing, fix it
SONNA explores the project first: lists folders, opens the files that matter, runs the failing test.
◆ list_dir . ◆ read_file src/auth.js ◆ $ npm test
Exact, unique edits for small changes. Whole files for new ones. Every write waits for your yes.
◆ edit_file src/auth.js ? edit src/auth.js? [y/N] y
It runs your tests again and reports back in plain words — what changed, and why it now works.
✓ 24 passing (412ms)
Fixed: expiry now uses
Date.now()/1000.
Everything an engineer does at a keyboard, with nothing it doesn't need.
Explores your project with list and read tools before it changes a single line.
list_dir · read_fileReplaces one exact, unique snippet — or writes a whole new file when that is the job.
edit_file · write_fileTests, builds, git. cmd.exe on Windows, /bin/sh on macOS and Linux.
run_commandEvery write and every command waits for your yes. Pass --yes only when you trust the task.
Claude Opus 5.5 with adaptive thinking — it reasons as hard as the problem needs.
claude-opus-5-5Paths are checked against the project root. Nothing outside it can be read or written.
sandboxed pathsEvery line on the right is a real SONNA session — scroll to play it.
Node.js 18+ or Bun. Set ANTHROPIC_API_KEY and begin.
$ export ANTHROPIC_API_KEY=sk-… $ npx sonna-agent
$ export ANTHROPIC_API_KEY=sk-… $ bunx sonna-agent
> $env:ANTHROPIC_API_KEY="sk-…" > npm i -g sonna-agent; sonna
The agent is MIT-licensed and free. It calls the Claude API with your own key, so you pay only for the API usage of your sessions.
Claude Opus 5.5 by default, with adaptive thinking. Pick another with --model or the SONNA_MODEL environment variable.
No. Every file write and every shell command waits for your y. Only --yes turns that off.
Yes. Commands run in cmd.exe on Windows and /bin/sh on macOS and Linux, and SONNA tells the model which shell it is in.
Pass the task as an argument — sonna "update the changelog" — and it runs once and exits with a status code.
One command. Your terminal. A calm agent that gets it done.