@flamecast/uplink

Expose a local MCP server to a Flamecast cast. npx @flamecast/uplink attaches the MCP server running on your laptop to a connection on your cast — agents in the cast can then call the local MCP's tools as if it were any other connection.

Quick start

# Foreground (blocks the terminal; Ctrl-C to stop):
npx @flamecast/uplink -- npx -y @playwright/mcp

# Background / daemon mode (returns immediately; slug is printed):
npx @flamecast/uplink up -- npx -y @playwright/mcp
npx @flamecast/uplink status
npx @flamecast/uplink down

# HTTP MCP server (already running on localhost):
npx @flamecast/uplink --url http://localhost:4000/mcp

On first run, your browser opens to authorize the CLI. Subsequent runs reuse the stored credentials. The cast is inferred from the WorkOS organization on your login — you don't pass it.

If you don't specify --slug, the CLI derives one from the local MCP target and prints it. Pass --slug <name> to override it explicitly.

Daemonized uplinks write logs and a PID file to ~/.config/flamecast/uplink/<cast>__<slug>.{log,pid}. Only one daemon is allowed per slug; up refuses to start if one is already running. down / status with no slug target every daemon running for your cast.

Reconnecting

Each uplink is identified by its cast + slug pair. If the CLI exits (Ctrl-C, crash, reboot) and you rerun with the same --slug, the cast's connection slot is reused — agents see it flip from disconnected back to connected. The slug is the identity, not the local command: pointing a different MCP at the same slug rebinds that slot.

Security

• The CLI only opens outbound traffic. No inbound ports are exposed on your machine.
• The local MCP is only reachable while the CLI is running — stopping the CLI severs the connection.
• Your authorization is scoped to the cast on your login.

Options

| Flag | Description | |---|---| | --slug <s> | Connection slug. Defaults to a sanitized name derived from the local MCP target for the foreground/up commands; acts as a filter on down/status. | | --url <url> | Bridge to an HTTP MCP server. | | -- <cmd> [args...] | Spawn a stdio MCP server. | | --api-url <url> | Flamecast API URL. Default https://api.flamecast.app. |

Commands

| Command | Effect | |---|---| | (none) | Run in foreground until Ctrl-C. | | up | Spawn a detached background process and return. | | down | Stop the background process for --slug, or every running daemon if no slug is given. | | status | Report the background process for --slug, or every running daemon if no slug is given. |