JanusMCP

Privacy Policy

Effective date: 28 June 2026

In short: JanusMCP runs entirely on your own computer. It has no backend servers, sends us no data, and contains no analytics or telemetry. Your credentials stay in your operating system's keychain and are used only to talk to the services you configure.

1. Who we are

JanusMCP ("the Software") is a free, open-source command-line tool published under the MIT license. The source code is available at github.com/bayway/janusmcp. The Software is a local broker for the Model Context Protocol (MCP): it sits between an LLM client on your machine and the MCP servers you choose to connect to.

2. What we collect

Nothing. JanusMCP does not operate any servers, does not phone home, and contains no analytics, tracking, advertising, or telemetry. The developers of JanusMCP receive no data about you or your usage.

3. Data the Software handles on your device

To do its job, JanusMCP processes the following locally, on your computer only:

Credentials and tokens (e.g. personal access tokens, OAuth tokens) that you add. These are stored in your operating system's secure keychain (macOS Keychain, Windows Credential Manager, or the Linux Secret Service), or, if you opt in, in an encrypted file on your disk. They are never written to configuration files in clear text and never sent to the developers.
Configuration — the list of accounts/services you define — stored in a local config.json on your machine.
Account selection state — which account is currently active — stored locally.

4. Data retention

Because everything is local, JanusMCP retains data only on your own device, for as long as you choose to keep it. Credentials stay in your keychain until you remove them (for example janusmcp vault delete <name> or via your OS keychain app); deleting your config.json or uninstalling the Software removes the rest. The developers retain nothing, because they receive nothing.

5. Network connections

JanusMCP only makes the network connections required to perform the actions you request:

To the MCP servers and APIs you configure (for example a Supabase or GitHub MCP server), using the credentials you provided for that account.
To an OAuth provider's authorization and token endpoints when you choose to log in via the browser, in order to obtain and refresh tokens.
When installed via npm, the package's post-install step downloads the matching prebuilt binary from this project's GitHub Releases.

JanusMCP does not route any of this traffic through servers controlled by its developers. When run in HTTP mode, the Software binds to your local loopback interface (127.0.0.1) by default.

6. Credentials and the model context

JanusMCP is designed so that secrets are not exposed to the language model. Tokens are resolved at connection time and used only to authenticate to upstream services; they do not pass through the chat/model context.

7. Third parties

The services you connect to (and the OAuth providers you authenticate with) are operated by third parties and governed by their own privacy policies. JanusMCP is not responsible for how those services handle your data.

8. Children

JanusMCP is a developer tool and is not directed to children under 13.

9. Changes

If this policy changes, the updated version will be published at this URL with a new effective date, and tracked in the project's public git history.

10. Contact

Questions or privacy concerns: open an issue or a private security advisory at github.com/bayway/janusmcp.