Mario wrote about why you might not need MCP. The problem: tool definitions are verbose. A single MCP server can burn 10k+ tokens, and you're paying that cost whether you use those tools or not. Connect a few servers and you've burned half your context window before the conversation starts.

His take: skip MCP entirely, write simple CLI tools instead.

Rhys wrote about the execution layer. The problem: MCP and CLI tools are usually just APIs with extra ceremony on top. Bash helped because it gave models an execution surface, but it doesn't solve the real problems: auth, approvals, permissions, state, and discoverability.

His take: use a real execution layer.

This adapter gives you access to that execution layer without the bloat.

Install

pi install npm:pi-executor

Restart or /Reload Pi after installation.

Pi extension that runs a cwd-scoped local Executor sidecar and exposes two agent facing tools and one skill to guide you agent into using executor.

Agent-facing tools

execute
resume only in headless / no-UI sessions

Executor discovery helpers stay inside Executor's runtime and are meant to be used from code executed via execute:

tools.search(...)
tools.describe.tool(...)
tools.executor.sources.list()

Commands

Command	What it does
`/executor-web`	Open the Web UI (manage sources)
`/executor-start`	Start the executor sidecar
`/executor-stop`	Stop the executor sidecar
`/executor-settings`	Executor local & global settings

Runtime model

configurable local or remote Executor endpoint per project
local mode uses one cwd-scoped Executor sidecar per working directory
healthy same-cwd local sidecars are reused across calls
Pi supervises only local sidecars it started itself
remote mode connects to piExecutor.remoteUrl and never spawns a local sidecar
the extension talks to Executor over HTTP
browser auth, source setup, and secret management stay in Executor's UI
execute mirrors MCP guidance and namespace discovery as closely as Pi allows
when Pi has UI, execute handles Executor interaction inline
when Pi has no UI, execute returns a paused interaction and resume is available

Install

bun install

Use in Pi

Settings

Configure the extension in ~/.pi/agent/settings.json or .pi/settings.json:

{
  "piExecutor": {
    "mode": "local",
    "autoStart": true,
    "remoteUrl": "",
    "showFooterStatus": true,
    "stopLocalOnShutdown": true
  }
}

mode: "local" or "remote"
autoStart: connect on session start
remoteUrl: required for remote mode
showFooterStatus: show the footer readiness dot
stopLocalOnShutdown: stop Pi-owned local sidecars on session shutdown

You can also manage these interactively with /executor-settings.

Use in Pi

Isolated project mode (loads only pi-executor, with no skills and no other extensions):

Project-local settings in .pi/settings.json also disable project-local skills/prompts/themes and point Pi at src/index.ts, but global Pi resources can still load unless you use the isolated command above.