# Background Agents: Open-Inspect

An open-source background agents coding system inspired by
[Ramp's Inspect](https://builders.ramp.com/post/why-we-built-our-background-agent).

## Overview

Open-Inspect provides a hosted background coding agent that can:

- Work on tasks in the background while you focus on other things
- Access full development environments (Node.js, Python, git, browser automation, VS Code)
- Connect from anywhere — web UI, Slack, GitHub PRs, Linear issues, or webhooks
- Enable multiplayer sessions where multiple people can collaborate in real time
- Create PRs with proper commit attribution to the prompting user
- Run on a schedule — cron jobs, Sentry alerts, and webhook-triggered automations
- Spawn parallel sub-tasks that work in separate sandboxes simultaneously
- Use your choice of AI model — Anthropic Claude, OpenAI Codex (via ChatGPT subscription), or
  OpenCode Zen

## Security Model (Single-Tenant Only)

> **Important**: This system is designed for **single-tenant deployment only**, where all users are
> trusted members of the same organization with access to the same repositories.

### How It Works

The system uses a shared GitHub App installation for git operations (clone, fetch, push). The
control plane mints short-lived installation tokens server-side and brokers them to sandboxes
through the git credential helper on demand. This means:

- **All users share the same GitHub App credentials** - The GitHub App must be installed on your
  organization's repositories, and any user of the system can access any repo the App has access to
- **No per-user repository access validation** - The system does not verify that a user has
  permission to access a specific repository before creating a session
- **GitHub users' OAuth tokens are used for PR creation** - For GitHub logins, PRs are created using
  the user's GitHub OAuth token, ensuring proper attribution and that they can only create PRs on
  repos they have write access to. Users who sign in another way (e.g. Google) carry no SCM token,
  so their PRs fall back to the shared GitHub App bot

### Token Architecture

| Token Type         | Purpose                                | Scope                            |
| ------------------ | -------------------------------------- | -------------------------------- |
| GitHub App Token   | Brokered git clone/fetch/push auth     | All repos where App is installed |
| User OAuth Token   | Create PRs, user info                  | Repos user has access to         |
| Sandbox Auth Token | Sandbox-to-control-plane session calls | Single session                   |
| WebSocket Token    | Real-time session auth                 | Single session                   |

### Why Single-Tenant Only

This architecture follows
[Ramp's Inspect design](https://builders.ramp.com/post/why-we-built-our-background-agent), which was
built for internal use where all employees are trusted and have access to company repositories.

**For multi-tenant deployment**, you would need:

- Per-tenant GitHub App installations
- Access validation at session creation
- Tenant isolation in the data model

### Deployment Recommendations

1. **Deploy behind your organization's SSO/VPN** - Ensure only authorized employees can access the
   web interface
2. **Install GitHub App only on intended repositories** - The App's installation scope defines what
   the system can access
3. **Use GitHub's repository selection** - When installing the App, select specific repositories
   rather than "All repositories"

## Architecture

```
                                    ┌──────────────────┐
                                    │     Clients      │
                                    │ ┌──────────────┐ │
                                    │ │  Web / Slack │ │
                                    │ │ GitHub / Lin.│ │
                                    │ │   Webhooks   │ │
                                    │ └──────────────┘ │
                                    └────────┬─────────┘
                                             │
                                             ▼
┌────────────────────────────────────────────────────────────────────┐
│                     Control Plane (Cloudflare)                     │
│  ┌──────────────────────────────────────────────────────────────┐  │
│  │                   Durable Objects (per session)              │  │
│  │  ┌─────────┐  ┌─────────┐  ┌─────────┐  ┌───────────────┐    │  │
│  │  │ SQLite  │  │WebSocket│  │  Event  │  │   GitHub      │    │  │
│  │  │   DB    │  │   Hub   │  │ Stream  │  │ Integration   │    │  │
│  │  └─────────┘  └─────────┘  └─────────┘  └───────────────┘    │  │
│  └──────────────────────────────────────────────────────────────┘  │
│  ┌──────────────────────────────────────────────────────────────┐  │
│  │              D1 Database (repo-scoped secrets)               │  │
│  └──────────────────────────────────────────────────────────────┘  │
└────────────────────────────────┬───────────────────────────────────┘
                                 │
                                 ▼
┌────────────────────────────────────────────────────────────────────┐
│                 Data Plane (Sandbox Backend)                       │
│  ┌──────────────────────────────────────────────────────────────┐  │
│  │                     Session Sandbox                          │  │
│  │  ┌───────────┐  ┌───────────┐  ┌───────────┐                 │  │
│  │  │ Supervisor│──│  OpenCode │──│   Bridge  │─────────────────┼──┼──▶ Control Plane
│  │  └───────────┘  └───────────┘  └───────────┘                 │  │
│  │                      │                                       │  │
│  │              Full Dev Environment                            │  │
│  │      (Node.js, Python, git, agent-browser)                   │  │
│  └──────────────────────────────────────────────────────────────┘  │
└────────────────────────────────────────────────────────────────────┘
```

## Packages

| Package                                     | Description                                 |
| ------------------------------------------- | ------------------------------------------- |
| [control-plane](packages/control-plane)     | Cloudflare Workers + Durable Objects        |
| [web](packages/web)                         | Next.js web client                          |
| [sandbox-runtime](packages/sandbox-runtime) | Shared in-sandbox agent runtime             |
| [modal-infra](packages/modal-infra)         | Modal sandbox infrastructure                |
| [daytona-infra](packages/daytona-infra)     | Daytona snapshot infrastructure             |
| [slack-bot](packages/slack-bot)             | Slack integration (sessions from messages)  |
| [github-bot](packages/github-bot)           | GitHub integration (auto-review, @mention)  |
| [linear-bot](packages/linear-bot)           | Linear integration (issue → coding session) |
| [shared](packages/shared)                   | Shared types and utilities                  |

## Getting Started

For a practical setup guide (local + contributor + deployment paths), start with
**[docs/SETUP_GUIDE.md](docs/SETUP_GUIDE.md)**.

See **[docs/GETTING_STARTED.md](docs/GETTING_STARTED.md)** for deployment instructions.

To understand the architecture and core concepts, read
**[docs/HOW_IT_WORKS.md](docs/HOW_IT_WORKS.md)**.

To set up recurring scheduled tasks, see **[docs/AUTOMATIONS.md](docs/AUTOMATIONS.md)**.

## Key Features

### Fast Startup

Sessions start near-instantly through multiple layers of warming:

- **Filesystem snapshots** — After each prompt, sandbox state is saved; follow-up sessions restore
  instead of re-cloning
- **Pre-built repo images** — Toggle per-repo in Settings; rebuilt every 30 minutes with latest
  commits and dependencies
- **Proactive warming** — Sandbox begins spinning up as soon as you start typing, before you hit
  Enter

### Multiplayer Sessions

Multiple users can collaborate in the same session:

- Presence indicators show who's active
- Prompts are attributed to their authors in git commits
- Real-time streaming to all connected clients

### Commit Attribution

Commits are attributed to the user who sent the prompt:

```typescript
// Configure git identity per prompt
await configureGitIdentity({
  name: author.scmName,
  email: author.scmEmail,
});
```

### Multi-Provider Model Support

Choose the AI model that fits your task, with per-session reasoning effort controls:

| Provider     | Models                                                               |
| ------------ | -------------------------------------------------------------------- |
| Anthropic    | Claude Haiku 4.5, Sonnet 4.5/4.6, Opus 4.5/4.6/4.7/4.8, Fable 5      |
| OpenAI       | GPT 5.2, GPT 5.4, GPT 5.5, GPT 5.2 Codex, 5.3 Codex, 5.3 Codex Spark |
| OpenCode Zen | Kimi K2.5/K2.6, MiniMax M2.5, Qwen3.7 Max, GLM 5/5.1 (opt-in)        |

OpenAI models work with your existing ChatGPT subscription via OAuth — no separate API key needed.
See **[docs/AVAILABLE_MODELS.md](docs/AVAILABLE_MODELS.md)** for the full model list and
**[docs/OPENAI_MODELS.md](docs/OPENAI_MODELS.md)** for OpenAI setup instructions.

### Client Integrations

Interact with agents from wherever your team already works:

- **Web UI** — Full session management with real-time streaming, model/reasoning selectors, terminal
  panel, and multiplayer presence
- **Slack Bot** — @mention or DM to start a session; replies thread back with results. Per-user
  model and branch preferences via App Home. See [Slack integration](docs/integrations/SLACK.md)
- **GitHub Bot** — Auto-review on PR open or respond to @mentions in PR comments. Configurable
  per-repo. See [GitHub integration](docs/integrations/GITHUB.md)
- **Linear Bot** — Mention or assign the agent on an issue to start a coding session, post progress
  activities, and link the resulting PR. See [Linear integration](docs/integrations/LINEAR.md)
- **Webhooks** — Trigger sessions from any external system via authenticated HTTP POST

### Automations

Schedule recurring tasks or react to external events — no human in the loop:

- **Cron schedules** — Hourly, daily, weekly, monthly, or custom 5-field cron with timezone support
- **Sentry alerts** — Auto-triage on new errors, regressions, or critical metric alerts
- **Inbound webhooks** — JSONPath condition filters to gate which payloads spawn sessions
- Auto-pause after 3 consecutive failures, manual trigger button, full run history

See **[docs/AUTOMATIONS.md](docs/AUTOMATIONS.md)** for setup instructions.

### Sandbox Environment

Every session runs in an isolated sandbox backend with a full development environment:

- **Pre-installed:** Node.js 22, Python 3.12, Bun, git, GitHub CLI, build-essential
- **Browser automation:** agent-browser CLI with headless Chromium for screenshots, visual diffs,
  and UI verification
- **Code-server:** Optional browser-based VS Code connected to the session workspace
- **Web terminal:** ttyd-powered terminal accessible from the session UI
- **Port tunneling:** Expose up to 10 dev server ports via encrypted tunnels. URLs are available
  in-sandbox at `/workspace/.tunnels.env` before `.openinspect/start.sh` runs
  ([details](docs/HOW_IT_WORKS.md#tunnel-urls-inside-the-sandbox))
- **Repo secrets:** AES-256-GCM encrypted, scoped per-repo or globally, injected as env vars at
  spawn time. Supports bulk `.env` paste import

### Sub-Task Spawning

Agents can decompose work into parallel child sessions:

- `spawn-task` creates a child session in its own sandbox and returns immediately
- Parent continues working while children run in parallel on separate branches
- `get-task-status` and `cancel-task` for coordination
- Depth limits and per-repo guardrails enforced

### Repository Lifecycle Scripts

Repositories can define two optional startup scripts under `.openinspect/`:

```bash
# .openinspect/setup.sh (provisioning)
#!/bin/bash
npm install
pip install -r requirements.txt
```

```bash
# .openinspect/start.sh (runtime startup)
#!/bin/bash
docker compose up -d postgres redis
```

- `setup.sh` runs for image builds and fresh sessions
- `setup.sh` is skipped for repo-image and snapshot-restore starts
- `setup.sh` failures are non-fatal for fresh sessions, but fatal in image build mode
- `start.sh` runs for every non-build session startup (fresh, repo-image, snapshot-restore)
- `start.sh` failures are strict: if present and it fails, session startup fails
- Default timeouts:
  - `SETUP_TIMEOUT_SECONDS` (default `300`)
  - `START_TIMEOUT_SECONDS` (default `120`)
- Both hooks receive `OPENINSPECT_BOOT_MODE` (`build`, `fresh`, `repo_image`, `snapshot_restore`)
- Git operations in hooks can authenticate to other private repos on the configured SCM host when
  the shared installation has access

## License

MIT

## Credits

Inspired by [Ramp's Inspect](https://builders.ramp.com/post/why-we-built-our-background-agent) and
built with:

- [Modal](https://modal.com) - Cloud sandbox infrastructure
- [Daytona](https://www.daytona.io) - Cloud development sandboxes
- [Vercel Sandbox](https://vercel.com/docs/vercel-sandbox) - Cloud sandbox infrastructure
- [Cloudflare Workers](https://workers.cloudflare.com) - Edge computing
- [OpenCode](https://opencode.ai) - Coding agent runtime
- [Next.js](https://nextjs.org) - Web framework