🗿 Road Poneglyph

An MCP server that reviews a plan for what's missing — the assumptions, risks, and gaps you never wrote down.

A Model Context Protocol (MCP) server — one focused tool you plug into an MCP-compatible client (Claude Desktop, Claude Code, Cursor, and others).

What it does

Language models are good at responding to what's in front of them and poor at noticing what isn't there. Ask one to critique a plan and it tends to react to the words on the page rather than the unstated assumptions behind them.

Road Poneglyph runs a structured pre-mortem over a plan and reports only the negative space — what was assumed without proof, what was technically glossed over, and what was skipped on the way to shipping.

Usage

Point your assistant at a plan and ask it to read the poneglyph. The tool returns a focused analysis in three sections:

• The Void Century — unstated assumptions the plan depends on
• Hidden Reef — omitted technical and architectural risks
• The Treacherous Seas — operational and execution blind spots

Tool reference: read_poneglyph(current_plan: str, project_type: str = "Software")

How it works

No API key, no cost, nothing leaves your machine. The server doesn't call a language model itself — it returns a carefully engineered analysis prompt that the model you're already talking to executes. Zero credentials, zero network calls.

Install

Requires Python 3.10 or newer.

pip install road-poneglyph-mcp

This installs the road-poneglyph command.

Then register it with your MCP client — either run claude mcp add road-poneglyph -- road-poneglyph, or add this to the client's config (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "road-poneglyph": { "command": "road-poneglyph" }
  }
}

Restart the client and the tool is available.

The Grand Line stack

Road Poneglyph is part of a four-tool set. Each tool stands alone, but installing all of them unlocks a final surprise via Laugh Tale.

Develop

git clone https://github.com/xfloukiex-lab/road-poneglyph
cd road-poneglyph
python -m venv .venv && . .venv/Scripts/activate   # macOS/Linux: source .venv/bin/activate
pip install -e ".[dev]"
python tests/test_road_poneglyph.py

Attribution & license

Released under the Apache-2.0 license. The icon is original artwork (see icon.svg), generated locally; the repository ships no third-party assets.

This is a fan-inspired project. It is not affiliated with, sponsored by, or endorsed by the creators or rights holders of One Piece (Eiichiro Oda / Shueisha / Toei Animation). "One Piece" and related names are used only as thematic flavour and remain the property of their respective owners.