MCP configuration

Connect an agent to Subshell's stdio MCP server.

Before you start

Launch the agent inside a Subshell pane. The MCP process needs SUBSHELL_API_KEY and SUBSHELL_ID, supplied by the host, plus the injected server address and state directory.

Do not paste pane credentials into shared configuration or copy them to another session. The credential identifies the pane's owner and is revoked when the pane is stopped.

Automatic integration

Claude Code, Codex, and OpenCode receive per-launch MCP configuration. Open the agent's tool list and verify that the subshell server exposes list_subshells.

The compiled server and node binaries both include an mcp subcommand. The host resolves which executable exists on the machine where the pane runs.

Manual integration

Hermes and pi require one-time host setup. In the server dashboard's sidebar, choose Presets → New preset and select the agent. Find Cross-subshell comms near the bottom of the form for the registration commands. Run those commands on the machine where that agent will execute. See Hermes Agent and pi.

For a node with subshell on PATH, a standard registration has this shape:

{
  "mcpServers": {
    "subshell": { "command": "subshell", "args": ["mcp"] }
  }
}

Use subshell-server or the displayed absolute executable where that is the resolved host command. The child process inherits the pane's identity environment.

Verify

Ask the agent to call list_subshells without modifying any session. A stdio MCP process may wait for protocol messages; running it by hand is not a general health-check command.

Next steps

Read Coordinate agents and MCP troubleshooting.