tsidp

Before configuring Proxmox, you must register it as an OIDC client within the tsidp web interface:

1. Navigate to your tsidp instance URL (e.g., https://idp.yourtailnet.ts.net).
2. Click Add New Client.
3. Configure the client by adding the Redirect URIs used to access your Proxmox server.
4. Save and record the generated Client ID and Client Secret; these are required for the Proxmox OpenID Connect configuration.

To host tsidp in Docker, create a new LXC in Proxmox with the following specific configuration:

• General: Enable "Unprivileged container" and enable "Nesting" (required for Docker).
• Template: Use alpine-3.21-default_20241217_amd64.tar.xz (or similar).
• Disks: 4 GiB.
• CPU: 1 Core.
• Memory: 512 MiB RAM + 512 MiB Swap.
• Note: Do not enable keyctl=1 as tsidp does not require Docker secrets.

To ensure the identity provider survives reboots, configure both the Docker container and the LXC to start automatically:

1. Docker: Set the container to restart unless stopped:

   docker update --restart unless-stopped tsidp

2. Proxmox LXC: In the Proxmox UI, select the container, go to Options $\rightarrow$ Start at boot, and set it to Yes.

Because Autocreate Users is enabled, tsidp users will be created in Proxmox automatically upon their first login, but they will have no permissions by default. To grant access:

1. Create a Group: Go to Datacenter $\rightarrow$ Permissions $\rightarrow$ Groups and create a group (e.g., tsadmins).
2. Grant Permissions: Go to Datacenter $\rightarrow$ Permissions. Add a Group Permission:
   • Path: /
   • Group: tsadmins
   • Role: Administrator
3. Assign Users: Go to Datacenter $\rightarrow$ Permissions $\rightarrow$ Users, edit the auto-created user, and add them to the tsadmins group.

To test the Security Token Server (STS) in tsidp, you must ensure an application grant is configured. For testing and development purposes, you can use a highly permissive grant that allows all sources, destinations, IPs, users, and resources for the tailscale.com/cap/tsidp capability.

"grants": [
  {
    "src": ["*"],
    "dst": ["*"],
    "ip":  ["*"],

    "app": {
      "tailscale.com/cap/tsidp": [
        {
          "users":     ["*"],
          "resources": ["*"]
        }
      ]
    }
  }
]

To run the tsidp server for the MCP gateway demo, use the following Docker command. This setup enables STS (Security Token Service) and dynamic client registration.

$ docker run -it --rm --name tsidp \
  -v tsidp-mcp-gateway-demo:/data \
  -e TS_STATE_DIR=/data \
  -e TS_HOSTNAME=tsidp-mcp-gateway-demo \
  -e TSIDP_ENABLE_STS=1 \
  -e TAILSCALE_USE_WIP_CODE=1 \
  -e TSIDP_LOG=debug ghcr.io/tailscale/tsidp:latest

To verify the server, use the MCP inspector. Due to known bugs in newer versions, it is recommended to use version 0.16.3 as of late 2025.

Authorization Flow

1. Set the transport type to Streamable HTTP.
2. Set the URL to http://localhost:9933.
3. Click Open Auth Settings.
4. Click Quick OAuth Flow and verify all checks pass.

Tool Execution

1. Click Connect.
2. Click List tools to see available capabilities.
3. Execute a tool call to verify end-to-end functionality.

npx @modelcontextprotocol/inspector@0.16.3

After creating and starting the LXC, access the console as root and run the following commands to set up the environment:

1. Install dependencies:

   apk update
   apk add docker git

2. Start Docker service:

   rc-service docker start
   rc-update add docker boot

3. Clone the repository:

   mkdir -p /usr/local/src && cd /usr/local/src
   git clone https://github.com/tailscale/tsidp.git

4. Build and run: Follow the project's main README instructions to launch tsidp via Docker.

To use the MCP server example, you must first have tsidp running. If you are using Docker, you can start the service with the following command. Ensure you replace YOUR_TAILSCALE_AUTHKEY with a valid Tailscale authentication key.

Note that the container uses a volume tsidp-data to persist data at /var/lib/tsidp and sets the hostname to idp.

docker run -d \
  --name tsidp \
  -p 443:443 \
  -e TS_AUTHKEY=YOUR_TAILSCALE_AUTHKEY \
  -e TSNET_FORCE_LOGIN=1 \
  -e TAILSCALE_USE_WIP_CODE=1 \
  -v tsidp-data:/var/lib/tsidp \
  tsidp --hostname=idp --dir=/var/lib/tsidp

MCP requires the use of resource indicators. You must add an ACL application grant to your tailnet to allow users or devices to specify resources in their requests.

For testing purposes, you can use the following permissive rule which allows any user/device to request any resource. For production, replace the "*" in resources with your specific resource URI (e.g., http://localhost:9933).

{
  "src": ["*"],
  "dst": ["*"],
  "app": {
    "tailscale.com/cap/tsidp": [
      {
        "users":     ["*"],
        "resources": ["*"],
      },
    ],
  },
}