otto

A local-first AI coding platform.

One runtime. Many surfaces. Your agents, your tools, your repo — on your machine.

Install · Surfaces · Agents & Tools · Embedding · Docs

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What is otto

otto is a local-first coding platform built around a single runtime — otto serve — that gives AI models controlled access to your repo through built-in tools: file IO, search, patching, git, terminals, web fetch, skills, MCP, and task tracking.

You pick the surface. The runtime, agents, tools, sessions, and providers stay the same across all of them.

• Local-first. Your code, your machine, your keys. Secrets live in OS-secure stores, not config files.
• Multi-provider. Anthropic, OpenAI, Google, OpenRouter, OpenCode, OttoRouter, Moonshot, Minimax, Z.AI — swap at runtime.
• Extensible. Custom tools, MCP servers, skills, and agent presets, per-project or global.
• Open. MIT-licensed, Bun monorepo, OpenAPI spec, embeddable server.

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Install

curl -fsSL https://install.ottocode.io | sh

Or via Bun:

bun install -g @ottocode/install

Then:

otto           # interactive TUI
otto --web     # web UI in your browser
otto serve     # run the API + web UI

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Surfaces

otto ships in multiple forms. Pick whichever fits the moment — they all share the same runtime, sessions, and config.

Surface	What it's for
CLI	One-shot prompts, scripts, CI, and terminal workflows
TUI	Full interactive session inside your terminal (default otto)
Web UI	Browser client for the local otto server
Desktop	Lightweight Tauri wrapper around the web UI
Canvas	Native tiled workspace — terminals, browsers, agents, side-by-side
Server	Embeddable Hono-based API you host in your own app
SDK	Auth, config, providers, tools, prompts, API client as packages
ACP adapter	Integrate otto with ACP-capable editors and tools

CLI

otto                                  # interactive TUI (default)
otto "explain this stack trace"       # one-shot prompt
otto "write tests" --agent build
otto "review the architecture" --agent plan
otto "research this codebase" --agent research
otto --last "continue"                # resume last session
otto --web                            # start API + web UI and open browser
otto serve --port 3000                # API on :3000, web UI on :3001
otto serve --network                  # bind for LAN access

Companion commands:

otto setup          otto auth login      otto auth list
otto doctor         otto sessions        otto models
otto agents         otto tools           otto skills
otto mcp list       otto scaffold

Canvas

Canvas is otto's native tiled workspace — a Tauri + React desktop app where each pane is a first-class block.

Block	What it does	Powered by
Terminal	GPU-rendered native terminal	Ghostty (libghostty)
Browser	Inline preview for localhost or any URL	macOS WKWebView
Otto	AI chat with full tool access to your repo	otto serve runtime
Claude Code	Claude Code in a Ghostty surface	Ghostty preset
Codex	OpenAI Codex in a Ghostty surface	Ghostty preset
Otto TUI	Run the otto TUI inside Canvas	Ghostty preset
OpenCode	OpenCode in a Ghostty surface	Ghostty preset
Custom command	Any shell command as a terminal block	Ghostty preset

• Multi-workspace — each workspace binds to a project path and launches its own otto serve runtime
• Tabs & splits — ⌘N add block · ⌘T new tab · ⌘D split right · ⌘⇧D split down · ⌘1-9 switch · Ctrl+H/J/K/L vim nav
• Shareable layouts — export tabs, splits, and presets as otto.yaml
• Native performance — libghostty + WKWebView, no Electron

Run locally:

cd apps/canvas
bun install
bun tauri dev       # dev mode
bun tauri build     # .app / .dmg

Canvas currently targets macOS. Linux and Windows support is on the roadmap.

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Agents

Built-in presets from @ottocode/server:

Agent	Purpose	Tool profile
build	Code changes, fixes, implementation	Full patch/search/shell
plan	Analysis and planning	Read/search/task
research	Cross-session and web research	Read/search/web + research DB
general	Mixed-purpose assistant	Broad workspace default

All agents include progress_update, finish, and skill.

Override per-project in .otto/agents.json or globally in ~/.config/otto/agents.json. Prompt files live at .otto/agents/<name>.md.

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Tools

The built-in tool surface available to agents:

Category	Tools
File system	read · write · ls · tree · pwd · cd · glob
Search	ripgrep · websearch
Editing	apply_patch
Shell	shell · terminal
Git	git_status · git_diff · git_commit
Agent control	update_todos · progress_update · finish · skill
Research	query_sessions · query_messages · get_session_context · search_history · get_parent_session · present_action

MCP servers

otto speaks MCP over stdio, HTTP, and SSE. Tools register as server__tool.

otto mcp add helius --command npx --args -y helius-mcp@latest
otto mcp add linear --transport http --url https://mcp.linear.app/mcp
otto mcp list
otto mcp auth linear

See docs/mcp.md.

Custom tools

Drop a plugin in .otto/tools/<name>/tool.js:

export default {
  name: 'file_size',
  description: 'Return the byte size for a file path',
  parameters: {
    path: { type: 'string', description: 'Path to inspect' },
  },
  async execute({ input, fs }) {
    const content = await fs.readFile(input.path, 'utf8');
    return { bytes: Buffer.byteLength(content, 'utf8') };
  },
};

See docs/customization.md.

Skills

Load markdown instruction bundles on demand with the skill tool. Sources:

• Built-in bundled skills
• .otto/skills/ · .agents/skills/
• ~/.config/otto/skills/ · ~/.agents/skills/

Run otto skills to list what's available.

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Providers

Set environment variables for the providers you want:

export ANTHROPIC_API_KEY="sk-ant-..."
export OPENAI_API_KEY="sk-..."
export GOOGLE_GENERATIVE_AI_API_KEY="..."
export OPENROUTER_API_KEY="..."
export OPENCODE_API_KEY="..."
export OTTOROUTER_PRIVATE_KEY="..."          # Solana wallet (base58)
export MOONSHOT_API_KEY="..."
export MINIMAX_API_KEY="..."
export ZAI_API_KEY="..."
export ZAI_CODING_API_KEY="..."

Full list: docs/environment.md.

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Configuration

Scope	Path
Global config	~/.config/otto/
Project config	.otto/
Auth (macOS)	~/Library/Application Support/otto/auth.json
Auth (Linux)	$XDG_STATE_HOME/otto/auth.json
Auth (Windows)	%APPDATA%/otto/auth.json

Secrets are stored in OS-secure locations — never in the config directory.

See docs/configuration.md.

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Embedding

Run the otto server inside your own app:

import { createEmbeddedApp } from '@ottocode/server';
import { serveWebUI } from '@ottocode/web-ui';

const api = createEmbeddedApp({
  provider: 'anthropic',
  model: 'claude-sonnet-4',
  apiKey: process.env.ANTHROPIC_API_KEY,
  agent: 'build',
});

const web = serveWebUI({ prefix: '/ui' });

Bun.serve({
  port: 3456,
  idleTimeout: 240,
  async fetch(req) {
    return (await web(req)) ?? api.fetch(req);
  },
});

See docs/embedding-guide.md.

API

The server exposes:

• / — root text response
• /openapi.json — generated OpenAPI document (source of truth for clients)
• /v1/* — operational routes: ask, auth, config, doctor, files, git, mcp, provider-usage, research, sessions, ottorouter, shares, skills, terminals, tunnel

See docs/api.md.

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Repository

A single Bun monorepo.

Apps (apps/) canvas · cli · desktop · intro-video · landing · launcher · mobile · preview-api · preview-web · tui · web

Packages (packages/) @ottocode/acp · @ottocode/ai-sdk · @ottocode/api · @ottocode/database · @ottocode/install · @ottocode/openclaw · @ottocode/sdk · @ottocode/server · @ottocode/web-sdk · @ottocode/web-ui

Infra (infra/) — SST modules script · landing · preview-api · preview-web · og

See docs/architecture.md.

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Development

git clone https://github.com/nitishxyz/otto.git
cd otto
bun install
bun lint
bun test
bun run typecheck
bun run compile

Common dev commands:

bun run dev:cli
bun run --filter @ottocode/tui dev
bun run dev:web
bun run dev:desktop
bun sst dev

See docs/development.md.

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Docs

• Getting Started
• Usage Guide
• Configuration
• Agents & Tools
• MCP
• API
• Architecture
• Embedding Guide
• Development
• Docs Index

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Contributing

Conventions in AGENTS.md. In short:

• Bun for everything (install, run, build, test)
• Biome for lint and format
• bun:test for tests
• TypeScript strict mode
• Small, focused PRs

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License

MIT