What is horizon-shield?

A read-only service that checks Japanese construction and renovation estimates against the open JCCDB price dataset. It returns receipts that others can independently recompute and that are anchored to Bitcoin.

It is for auditing Japanese building and renovation quotes and producing verifiable fair-price records.

It helps identify whether an estimate is consistent with published reference prices without changing the source data. The receipt gives reviewers a way to check the result independently.

horizon-shield — Plugin for Gemini CLI by ogasurfproject-jpg

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Clone the repo

git clone --depth 1 https://github.com/ogasurfproject-jpg/horizon-shield

Made for: Gemini CLI.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/plugins/ogasurfproject-jpg/horizon-shield/gemini-extension/github.svg)](https://agentmods.dev/plugins/ogasurfproject-jpg/horizon-shield/gemini-extension)

Your own site

<a href="https://agentmods.dev/plugins/ogasurfproject-jpg/horizon-shield/gemini-extension"><img src="https://agentmods.dev/badge/plugins/ogasurfproject-jpg/horizon-shield/gemini-extension/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/plugins/ogasurfproject-jpg/horizon-shield/gemini-extension"><img src="https://agentmods.dev/badge/plugins/ogasurfproject-jpg/horizon-shield/gemini-extension.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session not measured What this adds to a session before it is invoked.

When invoked not measured Not applicable: nothing here is loaded into a session.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Security

Grade A, and why

horizon-shield scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 17d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

gemini-extension.json · 12 lines

What it actually says

{
  "name": "horizon-shield",
  "version": "1.1.0",
  "description": "Audit Japanese construction and renovation estimates against the open JCCDB dataset and return Bitcoin-anchored, independently recomputable fair-price receipts. Remote MCP server, read-only, no API key.",
  "mcpServers": {
    "horizon-shield": {
      "httpUrl": "https://mcp.horizonshield.dev/mcp"
    }
  },
  "contextFileName": "GEMINI.md"
}

Files

What ships with it

60 files beside gemini-extension.json in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

17d ago Changed 07959e029181
1mo ago First seen · 12 lines scan A 721f812958dd

Subscribe to this mod's changes

horizon-shield is a plugin published in the GitHub repository ogasurfproject-jpg/horizon-shield (2 stars, last pushed yesterday), licensed MIT. Its token cost is not measured: this kind of file is read by the harness, not the model. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-07.

Analytics and metrics Scientific a2a ai-agents gemini-cli-extension mcp mcp-server model-context-protocol

horizon-shield

Getting it into your agent

Wrote this? Show the measurements

Grade A, and why

Nothing flagged

What it actually says

What ships with it

What this file has done since we first saw it

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