reticle mcp

Run the MCP stdio proxy your agent talks to, starting a daemon if one is not already up.

reticle mcp is the command your agent runs. It is the MCP server the editor launches: a stdio proxy that bridges the client to the daemon’s SSE endpoint, starting a daemon first if the port is empty.

npx @reticlehq/server mcp [--port N] [--drive <url>] [--headless] [--headed] [--http] [--http-port N] [--http-token T]

This is what reticle init registers, so you rarely type it yourself.

Flags

Flag	Type	Default	What it does
--port N	number	4400 (or RETICLE_PORT, or the port in .reticle.json)	Bridge port
--drive <url>	string	unset	Have the daemon launch its own browser at this URL, so the agent has autonomous control without relying on your tab
--headless	boolean	true for mcp	Hide that browser
--headed	boolean	false	Show it
--http	boolean	false	Forward the HTTP verify endpoint flags to the daemon it spawns
--http-port N	number	unset	Port for that endpoint
--http-token T	string	unset	Bearer token for it

The rule this command lives by

The proxy is the MCP server the editor launched. Nothing respawns it, so an uncaught throw here is what a user experiences as “the MCP server disconnected”. Three behaviours follow from that:

• Crash handlers write to the proxy’s own log file, not just stderr, because the editor swallows stderr.
• A daemon that is not there is not fatal. The proxy answers initialize itself, serves the cached tool catalog, and retries a daemon on every client request. Present and complaining beats absent, because absent needs a human.
• Reconnect is self-healing: if the daemon exited, crashed, was stopped, or shut itself down as idle, the reconnect path spawns a new one rather than retrying a dead port until the budget runs out.

What it prints

Structured lines to the proxy log (~/.reticle/), not to your terminal, since stdout is the MCP transport.

Event	Meaning
reticle_mcp_daemon_started	It spawned a daemon
reticle_mcp_daemon_unavailable	It could not, and is serving anyway
reticle_mcp_proxy_first_connect_failed	The first connect was refused. Expected when the daemon is still coming up

Exit codes

Runs for the life of the editor session.

Worked example

{
  "mcpServers": {
    "reticle": { "command": "npx", "args": ["@reticlehq/server", "mcp"] }
  }
}

The tools this exposes

The full surface your agent gets once this is registered.