pi-piper-tts

A Pi package that adds a /piper-tts slash command (and a /tts alias).

What it does

/piper-tts speaks the latest assistant message from the current session branch using local Piper TTS.

It:

• waits for Pi to finish the current turn
• scans the active branch for the most recent assistant message
• extracts only spoken text blocks
• normalizes whitespace
• calls Piper locally through pi.exec()

Install

Install from npm:

pi install npm:@dmille56/pi-piper-tts

Or pin a version:

pi install npm:@dmille56/pi-piper-tts@0.1.0

Install from a local path while developing:

pi install /absolute/path/to/pi-piper-tts

Requirements

• Pi with package support
• Python 3
• Piper (piper-tts) installed locally:

Up-to-date install/docs: https://github.com/OHF-Voice/piper1-gpl

pip install piper-tts

• ffplay installed (from ffmpeg) and available on your PATH
• A Piper voice/model downloaded and available locally

Configuration

You can configure /piper-tts (and the /tts alias) using environment variables (highest priority) and/or Pi settings.json.

Environment variables

Set these environment variables before launching Pi:

• PIPER_PI_MODEL — required. Piper voice/model identifier or path passed to -m
• PIPER_PI_BIN — optional. Overrides the Piper command. Default is python3 -m piper
• PIPER_PI_DATA_DIR — optional. Passed to Piper as --data-dir
• PIPER_PI_EXTRA_ARGS — optional extra arguments appended to the Piper command
• PIPER_PI_MAX_CHARS — optional safety cap for long assistant messages (must be a positive integer)

Pi settings (settings.json)

Alternatively (or in addition), you can set configuration in settings.json.

Supported section/key names:

• pi-piper-tts (preferred)
• pi-tts-command (legacy alias)
• tts
• piper

Keys in that section:

• piper-pi-model — required (same value as PIPER_PI_MODEL)
• piper-pi-bin — same as PIPER_PI_BIN
• piper-pi-data-dir — same as PIPER_PI_DATA_DIR
• piper-pi-extra-args — same as PIPER_PI_EXTRA_ARGS
• piper-pi-max-chars — same as PIPER_PI_MAX_CHARS

Pi loads settings from:

• ~/.pi/agent/settings.json (global)
• <cwd>/.pi/settings.json (project override, takes precedence)

Example settings.json:

{
  "pi-piper-tts": {
    "piper-pi-model": "/path/to/your/voice.onnx",
    "piper-pi-data-dir": "$HOME/.local/share/piper",
    "piper-pi-bin": "python3 -m piper",
    "piper-pi-extra-args": "--speaker 0",
    "piper-pi-max-chars": 8000
  }
}

Quick environment-variable example

export PIPER_PI_MODEL=/path/to/your/voice.onnx
export PIPER_PI_DATA_DIR=$HOME/.local/share/piper
pi

If you want to override the command used to start Piper:

export PIPER_PI_BIN="python3 -m piper"

You can also add extra arguments:

export PIPER_PI_EXTRA_ARGS="--speaker 0"

Usage

Once Pi is running, type one of:

/piper-tts

or the convenience alias:

/tts

Pi will speak the latest assistant message aloud.

/tts alias (optional)

By default, this extension registers both commands:

• /piper-tts (primary)
• /tts (alias for /piper-tts)

If you want to disable the /tts alias (it will be unregistered):

Environment variable (highest priority):

export PIPER_PI_ENABLE_TTS_ALIAS=0

Pi settings.json (global: ~/.pi/agent/settings.json, or project: <cwd>/.pi/settings.json):

{
  "pi-piper-tts": {
    "enable-tts-alias": false
  }
}

This is read when the extension loads; you may need to restart (or `/reload`) after changing it.

Behavior

If something is wrong, the command will notify you and leave the session unchanged.

Common cases:

• no assistant message yet
• latest assistant message has no text
• PIPER_PI_MODEL is missing
• Piper is not installed (or ffplay is missing)
• the configured voice/model cannot be loaded

Publishing

This package is ready to publish to npm.

npm publish

Notes

• The extension is implemented in TypeScript and does not require compilation.
• It uses argument arrays with pi.exec() and does not shell-escape a single command string.
• It is local-only after installation.