Constellation Instance keeps an installed agent available across clients and experiences. It manages the agent's identity, configuration, private state, and lifecycle, while a selected ACP engine performs reasoning and tool execution.
Use it independently or with other Constellation components. It includes browser administration, a management API, and an ACP attach command.
Download the matching consumer bundle from Releases and extract it. Keep its files together. The bundle includes the executable, private Python interpreter, setup support, and the selected native engine; it needs no developer tools or system Python.
From the extracted folder, run:
./agent-instance setup --home "/path/to/my-agent" --name "My agent"On Windows, use agent-instance.exe with the same arguments. Choose a new private
folder for the installation, then follow the setup output for its address and
sign-in instructions. Connect a model account separately after installation.
Read native platform setup for OS requirements and startup behavior. Linux requires an explicit administrator step for the Instance PAM sign-in policy; setup does not silently change system authentication. Windows sign-in uses the owning account's password, not a Windows Hello PIN. macOS executables are unsigned previews.
Point a compatible ACP client at the installed agent:
command: /path/to/my-agent/bin/agent-instance
args: ["acp", "--home", "/path/to/my-agent"]
The engine determines the agent's supported reasoning and tool capabilities. See the ACP connection guide for local and remote access.
- Native setup, updates and rollback.
- Management API for configuration and installation controls.
- Source installation for developers and administrators.
- Interface map and validation for contributors.
Each installation keeps its own private files and credentials. An optional fleet interface is a client of these controls, not a required service.
Note
This project is not currently accepting external contributions, but we're actively working toward opening this up. We value community input and look forward to collaborating in the future. For now, feel free to fork and experiment!
Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit Contributor License Agreements.
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This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.
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