Tessera

An open-source web and desktop workspace for AI coding agents.

Tessera is an open-source workspace that turns AI coding agents into a visual command center for parallel software work.

Open source | Claude Code + Codex + OpenCode | Full CLI workflows in UI | From idea to pull request | Desktop + browser

Product Demos

Parallel agent workspace

Run Claude Code, Codex, and OpenCode agents in parallel while keeping each task, worktree file, and diff visible in a multi-panel workspace.

Kanban board workflow

Move work across the board with drag-and-drop, create new work with AI-generated titles, and organize tasks by collection.

Realtime Git worktree tracking

Track each task's worktree, branch, diff, PR state, and workflow status as agents continue working.

Rich composer controls

Open new panels, continue an existing conversation, tune reasoning, select models, choose permissions, use voice input (browser runtime only), add @ references, attach images, and send context-rich prompts from one composer.

Cross-platform agent workspace

Use the same multi-agent workspace in the browser, on macOS, or on Windows while running Claude Code, Codex, OpenCode, and their model choices side by side.

Skills dashboard

Browse locally discovered Claude Code skills by category, review plugin and skill counts, search available skills, favorite frequently used skills for quick access, and generate an analysis from the selected model.

Install

Choose the runtime that fits your setup:

macOS release DMGs are Developer ID signed and notarized. Windows portable .exe builds are not code-signed yet, so Windows SmartScreen may show an unknown-publisher warning. See Desktop Releases.

For the browser runtime:

npm install -g @horang-labs/tessera
tessera

Tessera prints the local browser URL after startup:

Tessera is running at:
  http://127.0.0.1:32123

Press Ctrl+C to stop.

The default port is 32123. If that port is already in use, Tessera scans upward and prints the actual URL it selected.

To request a specific port:

tessera --port 3100

Core Features

Tessera is designed for developers who run multiple AI coding sessions and need more structure than terminal tabs:

Also included: keyboard-first navigation, browser-native voice input through the Web Speech API in the browser runtime, and a Claude Code skills dashboard discovered from the local environment.

Technical Highlights

Tessera is built around a local runtime and provider-based CLI layer:

• Provider adapter architecture: each CLI is isolated behind a CliProvider contract for process lifecycle, protocol parsing, runtime controls, approvals, interrupts, and skills.
• Protocol normalization layer: Claude Code stream-json, Codex app-server, and OpenCode ACP JSON-RPC events are translated into a shared realtime message model.
• Agent workspace model: chats, tasks, collections, workflow states, managed git worktrees, PR state, diffs, provider controls, and interactive prompts are modeled as first-class workspace concepts.
• OpenCode model bridge: Tessera reads OpenCode's model catalog and exposes configured models, providers, and reasoning variants in the workspace.
• Shared local runtime: desktop and browser runtimes share the same local server, provider layer, and configurable app-data directory.

First Run

On first run, Tessera opens a setup flow.

1. If you are using the npm browser runtime, create the first local account. No default password is created. The desktop app does not require this step.
2. Confirm that at least one supported provider CLI is installed and authenticated.
3. Add or select a project folder.
4. Start a chat for exploration or create a task for worktree-backed implementation.

For provider login, use the provider's own CLI first, for example claude login, codex login, or OpenCode's configured provider credentials.

Supported CLIs

Provider-specific implementation lives under src/lib/cli/providers/. The rest of the app talks to the shared provider contract instead of CLI-specific internals.

Requirements

• Node.js 20 or later
• npm 10 or later
• At least one supported CLI installed and authenticated:
  • Claude Code CLI
  • Codex CLI
  • OpenCode CLI

You can check your local tools with:

node -v
npm -v
claude --version
codex --version
opencode --version

Build From Source

For development, clone the repository and install dependencies:

git clone https://github.com/horang-labs/tessera.git
cd tessera
npm install

Tessera uses a custom Node.js server for the Next.js app, WebSocket transport, database initialization, provider bootstrapping, and background pollers. Run server.ts instead of starting Next.js directly:

PORT=3100 npx tsx server.ts

Supported environment variables:

Desktop release builds use Electron:

Electron build outputs are written under release/.

Stored Data And Privacy

Tessera runs locally and stores app data under ~/.tessera/ by default.

Tessera includes anonymous telemetry in published npm and desktop builds to measure minimal usage. Telemetry is collected with PostHog and stored in the US region.

Tessera does not collect sensitive data such as IP addresses, prompts, messages, file paths, command output, repository names, or account details. You can disable telemetry during onboarding or later in Settings. Local source development runs do not send telemetry unless TESSERA_TELEMETRY_LOCAL=1 is set.

Common default paths:

Back up the data directory if you want to preserve Tessera's local state.

Provider requests are handled by the provider CLIs installed on your machine. Tessera does not replace the provider's authentication, billing, model access, or network behavior.

Tech Stack

Desktop Releases

Desktop release assets are built by GitHub Actions for v* tags and attached to GitHub Releases:

• Windows portable .exe (not code-signed yet)
• macOS .dmg for Apple Silicon and Intel, Developer ID signed and notarized

macOS release DMGs are signed and notarized with Apple Developer ID, so downloaded releases should open normally on macOS.

Windows release builds are portable .exe files and are not code-signed yet. SmartScreen may show an unknown-publisher warning; choose More info and then Run anyway to start Tessera.

If Gatekeeper still blocks a macOS release DMG, please report it as a release-signing issue.

See macOS Distribution for local and CI setup.

Status

Tessera is currently published as a beta. Ideas, bug reports, usability feedback, and feature requests are welcome through GitHub Issues, and we actively review them while Tessera evolves. External code contributions are not being accepted yet while the project structure and review process settle.

Teams And Design Partners

Tessera is currently focused on individual local workflows, but we are preparing team and enterprise features for companies running coding agents across multiple developers.

The team product is being shaped around three areas: shared workspaces for parallel agent work, governance for permissions and tool use, and operational visibility into agent usage, cost, and review state.

If your team wants to use Tessera in production, join the design partner waitlist.

Roadmap

Planned areas include:

Troubleshooting

claude, codex, or opencode is not found

Install the CLI you want to use, authenticate it, and make sure the command works in the same terminal where you run tessera.

Provider status says needs_login

Run the provider's login or setup command, then refresh Tessera's provider status.

Reset local login keys

If login tokens become invalid after moving files between machines, stop Tessera and remove the generated auth keys:

rm -rf ~/.tessera/auth
tessera

If you start Tessera with TESSERA_DATA_DIR, remove the auth/ directory under that custom data directory instead.

License

Tessera is open source under the Apache License 2.0 (Apache-2.0).

Copyright (c) 2026 Horang Labs, Inc.

See the LICENSE file for the full text.

Claude Code is a trademark of Anthropic. Codex and OpenAI are trademarks of OpenAI. Tessera is not affiliated with or endorsed by Anthropic or OpenAI.