Ethics Check MCP

Ethics Vibe Check

A gut-check button for AI conversations.

MCP tools that run an independent second-opinion model over an exchange so you can catch sycophancy, confirmation bias, or quiet drift — when you ask, not as ambient surveillance.

Package: @r-huijts/ethics-vibe-check · Repo: r-huijts/ethics-check-mcp

What it is

LLMs are trained to be helpful. That often means they agree too easily and let a chat slide toward whatever you already believe.

This server does not intercept every turn. It exposes tools you (or your host, when you ask) call mid-conversation:

“Sanity check that.” · “Play devil’s advocate.” · “Are we drifting?”

A second model grades the exchange. Reuse (or omit) a session id to get a sessionTrend — escalating / improving / stable — so creep shows up as a signal, not a pile of disconnected snapshots.

Quick start

1. MCP server

Cursor one-click (above) installs the server command only. Afterward, open MCP settings and add env (Gemini by default):

{
  "mcpServers": {
    "ethics-vibe-check": {
      "command": "npx",
      "args": ["-y", "@r-huijts/ethics-vibe-check"],
      "env": {
        "ETHICS_PROVIDER": "gemini",
        "GEMINI_API_KEY": "your_actual_gemini_api_key_here"
      }
    }
  }
}

Local second opinion (no cloud):

"env": {
  "ETHICS_PROVIDER": "ollama",
  "OLLAMA_MODEL": "llama3.2",
  "OLLAMA_BASE_URL": "http://127.0.0.1:11434"
}

CLI:

npm install -g @r-huijts/ethics-vibe-check
npx @r-huijts/ethics-vibe-check

Full env reference: env.example.

2. Companion skill (recommended)

The skill teaches the host when to call tools, how to treat sessionTrend, and when to record feedback. Prefer it over a fat always-on rule.

# global install:
ethics-vibe-check-install-skill

# from a clone / local package:
npm run install-skill

# one-shot without a global install:
npx -y -p @r-huijts/ethics-vibe-check ethics-vibe-check-install-skill

Installs skills/ethics-vibe-check/SKILL.md → ~/.cursor/skills/ethics-vibe-check/ (override with CURSOR_SKILLS_DIR).

Optional always-on checkpoint templates: docs/system-prompts.md.

Tools

Session / drift

• Pass the same sessionId across checks in one chat when you can.
• If omitted, the server uses a process-scoped default (typical MCP hosts run one process per conversation).
• Override with ETHICS_SESSION_ID for evals or known ids.

Calibration

Prompts are written so ordinary helpful replies can return low risk and empty findings. Empty is a valid gut-check result — not a failure.

Providers

Storage defaults to ~/.ethics-vibe-check/data (ETHICS_DATA_DIR to override).

With Gemini, analysis leaves your machine — don’t paste secrets you wouldn’t send to a third-party API. Use Ollama for local-only checks.

Example flow

1. Mid-chat: “Sanity check that last answer — did you just agree with me too easily?”
2. Host calls critical_thinking with the reply + your request (session id optional but nice).
3. If sessionTrend.riskTrend is escalating, the host should say so up front.
4. Later: “That pushback helped.” → ethics_feedback with useful: true.

Develop / verify

npm install
cp env.example .env   # or ETHICS_PROVIDER=mock for offline work
npm run build
npm run test:all      # session unit tests + calibration fixtures (mock)

More detail: USAGE.md.

Who this is for

Yes if you want a deliberate pause when a chat feels too comfortable, and you’ll act on an uncomfortable answer.

No if you want the model to always agree, or you need fully automatic enforcement with zero prompting — that’s a different product.

License

MIT © 2024–2026

The point isn’t to be right. The point is to be thoughtful.