pi-subagent-mcp

MCP server that exposes pi (pi --mode rpc) as a sub-agent for MCP-capable coding assistants (e.g. Kimi CLI).

Build

npm install
npm run build

Tools

Tool	Purpose
pi_dispatch	Spawn a pi session on a task (task, cwd, model?, name?, interactive?, approve?) → {taskId}
pi_send	Message a task (mode: auto/prompt/steer/followUp)
pi_status	State, streaming flag, last assistant text, current tool, pendingRequest
pi_read	Incremental event buffer read (since seq)
pi_wait	Block until the run finishes or a dialog needs answering; returns last assistant text + pendingRequest
pi_respond	Answer a pendingRequest dialog (value / confirmed / cancelled)
pi_abort	Abort current operation; session stays alive
pi_close	Kill the process, drop the task
pi_list	All tasks

Extension UI dialogs (bidirectional interaction)

pi extensions can block on select/confirm/input/editor dialogs (extension_ui_request). By default (interactive: true) the server surfaces these as pendingRequest in pi_status/pi_wait — which returns early — and the caller answers with pi_respond. With interactive: false (unattended runs) dialogs are auto-cancelled, preserving the original behavior.

Note: project-local pi extensions (.pi/extensions/) only load when the project is trusted — pass approve: true to pi_dispatch to grant that for the run. Also, pi delays the command response for extension commands that block on a dialog; the server therefore treats dialog activity as command acceptance so pi_dispatch/pi_send return instead of deadlocking.

Configuration

Environment variables:

• PI_SUBAGENT_SESSION_DIR — where pi session files are stored (default: .pi-subagent/sessions/ next to the package).
• PI_SUBAGENT_PI_PATH — override the pi binary path (default: pi).

MCP registration (example): point your client at node /path/to/dist/src/server.js.

Test

npm test   # unit + smoke + (if pi is installed and logged in) integration

Additional end-to-end scripts in scripts/ (acceptance-test.mjs, mcp-e2e-test.mjs, dialog-e2e-test.mjs). Issues found during development are logged in docs/issues/.