AIOSpiclientextensionharnessskills

Pi coding agent is now a first-class AIOS client

RTRexAI Team2026-09-112 min read

Pi coding agent is now a first-class AIOS client¶

Pi is a minimal, self-extensible terminal harness: four tools by default (read, write, edit, bash), everything else as TypeScript extensions, skills, and Pi packages. That philosophy matches AIOS — so instead of treating Pi as "another CLI that reads AGENTS.md", AIOS now embeds into it.

What landed¶

Registry: pi / pi-coding-agent alongside the existing clients, with skills, native, and harness capabilities. Pi ships no sub-agents, so AIOS claims no team/agents capability until an extension verifies it.
No fake MCP: Pi has no built-in MCP surface, and AIOS does not pretend otherwise. The registry models Pi as MCP-less (format: none, empty scopes), so every migration/proxy/codemap collector skips it safely.
Native + skills: a Pi instruction layer (client-sources), project skills at .pi/skills, global skills at ~/.pi/agent/skills, and all 25 AIOS skills projected (sync-skills reports skills pi -> installed=25).
Runtime: ctx-agent one-shot (pi -p) and interactive builders, a harness one-shot strategy, shell-bridge support with Pi package commands (install, update, config…) kept out of the wrapper.

Code-level, not prompt-level¶

The aios-pi-extension package (packages/aios-pi) is the real upgrade:

Four model-callable tools backed by the real CLI surface: memory recall/write/feedback (memo search/add/useful) and skill search.
A tool_call gate that blocks destructive shell (rm -rf, --no-preserve-root, fork bombs, mkfs, dd to devices) and protected writes (.env*, node_modules/, .git/).
A before_agent_start injection of the workflow policy plus a memory digest — deterministic even with --no-context-files.
aios init --agent pi registers the entry into ~/.pi/agent/settings.json, so install governs the plugin surface.
A pi --mode rpc JSONL driver (scripts/lib/pi/rpc-client.mjs) for long-lived managed sessions: correlated commands, settle detection, and fail-closed handling of Pi permission dialogs.

Try it¶

aios init --agent pi --dry-run
node scripts/aios.mjs harness run --provider pi --dry-run --objective "pi smoke"
node --test scripts/tests/pi-extension.test.mjs scripts/tests/pi-rpc-client.test.mjs

Live-load verification (pi -p with the extension) and package publication are next. The unit contract — 8 extension tests, 7 RPC tests, plus the full client matrix — is already green.

Pi coding agent is now a first-class AIOS client¶

What landed¶

Code-level, not prompt-level¶

Try it¶

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