ExtensionContext@piex-dev/btw

btw — Ephemeral Side Questions, Not Remembered

TL;DR

/btw lets you ask a side question with full context; the Q&A never enters the session — like whispering to your neighbor mid-meeting.

Overview

The classic dilemma: you want to ask something related to the current task but not have it "taken seriously". E.g. while debugging you ask "what's this project's Docker base image?" — sending it directly makes the agent treat it as task context, weighing "the user asked about Docker" on every later turn. @piex-dev/btw's answer: the question never goes to the agent. The extension takes a session snapshot, makes a side model call, and shows the answer. Nothing is left in the session.

How it works

Core mechanism: side call. The extension bypasses the agent loop and uses pi-ai's completeSimple for a one-shot request. Since the Q&A never enters the session, "anti-pollution" shifts from runtime filtering to an architectural guarantee: there's nothing to filter.

flow

/btw cmd → resolve model & creds → build snapshot (≤40K chars)
→ completeSimple(model, { systemPrompt, messages })
→ render answer into a Markdown pager (scrollable, interruptible)
→ no write to the session

The snapshot is a compressed summary (only user/assistant messages, toolCall kept as name(args), truncated from the head past 40K chars). A dedicated model can be configured (~/.pi/piex-dev/btw/btw.json) — side questions rarely need a flagship model. Waiting shows a BorderedLoader (Esc aborts), the answer a homegrown Markdown pager (j/k scroll, PgUp/PgDn, Home/End, progress %).

Usage

Install

bash

pi install npm:@piex-dev/btw

Source: extensions/btw

Usage

bash

/btw what's this project's Docker base image?

The answer shows in the pager; after closing, the session is untouched.

Configuration

~/.pi/piex-dev/btw/btw.json:

json

{ "model": "anthropic/claude-haiku-4-5", "thinkingLevel": "low" }

Falls back to the current session model if unset. Config is re-read each question, no /reload needed.

Verify

bash

pi -e ./extensions/btw/src/btw.ts -p "what is 1+1" --no-session

Implementation

~700 lines, single file. Core modules: /btw command, loadCompleteSimple (compatible with pi-ai 0.79 root export and 0.80 /compat subpath), resolveBtwModel (config→current-model fallback + cred check), buildConversationContext (compressed snapshot), completeSideQuestion (AbortSignal), BtwAnswerPager (Markdown scroll reader).

omp btw	btw (piex)
engine-level side call	`completeSimple` side call
never writes to session	same (architectural guarantee)
Bun runtime	Node.js (pi)

Design notes

Project	Mechanism	piex choice
pi-extensions pi-btw	`completeSimple` side call + session snapshot + settings file + loader/pager UI	Adopted the overall architecture, keeping piex's arg-less interactive input; pi-ai 0.79/0.80 compat loading reused directly

Changelog

Roadmap

Direction	Plan
Snapshot lacks system prompt & full tool results	selectively carry by relevance (e.g. always keep the last toolResult full text)
No multi-turn follow-up	add an input line in the pager; follow-up carries the prior turn (still no session write)
Model config hot-update	add a `/btw model` quick config command

Version history

Version	Date	Changes
0.1.0	2026-07-19	inject + filter architecture: `[BTW]` question injected into the main agent loop, tools disabled by prompt, later filtered via a `context` hook guessing "skip next assistant"
0.2.0	2026-07-21	side-call architecture: `completeSimple` one-shot request + ≤40K session snapshot, Q&A never writes to session; adds `btw.json` dedicated model/thinking level, interruptible loader, Markdown pager

0.1.0 lesson: "pollute first, clean later" is hard to do strictly in an async message stream — when an assistant reply carries a toolCall sequence the filter guess misaligns and leaks; when the agent is busy, queued messages let the btw marker land on the wrong turn. 0.2.0 switches to "don't produce pollution", and the whole class of boundary issues vanishes.

Source Markdown: docs/packages/btw.md