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PopNx MCPMCP servers for people who use AI · explained in plain words

Fairseal MCP

by ned-delversion 0.2.4i★ –iRuns on your computer
Registry nameio.fairseal/mcp-server

Install

Overview

Description from the maker (original English)

Verifiable entropy, provably-fair games, and receipt verification for AI agents (FairSeal API).

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs on your computer
  • Transport: stdio
  • Category: Other
  • You need to fill in: FAIRSEAL_API_KEY, FAIRSEAL_NOTARY_API_KEY, FAIRSEAL_ANCHOR_API_KEY

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on your computer with your user’s permissions (files, network, apps).
  • You fill in yourself: FAIRSEAL_API_KEY, FAIRSEAL_API_URL, FAIRSEAL_NOTARY_API_KEY, FAIRSEAL_ANCHOR_API_KEY

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

  • npmNode.js installed (for the npx command)

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "fairseal": {
      "command": "npx",
      "args": [
        "-y",
        "@fairseal/mcp-server"
      ],
      "env": {
        "FAIRSEAL_API_KEY": "your-value",
        "FAIRSEAL_API_URL": "your-value",
        "FAIRSEAL_NOTARY_API_KEY": "your-value",
        "FAIRSEAL_ANCHOR_API_KEY": "your-value"
      }
    }
  }
}

Run this in your terminal

claude mcp add fairseal --env FAIRSEAL_API_KEY=your-value --env FAIRSEAL_API_URL=your-value --env FAIRSEAL_NOTARY_API_KEY=your-value --env FAIRSEAL_ANCHOR_API_KEY=your-value -- npx -y @fairseal/mcp-server

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "fairseal": {
      "command": "npx",
      "args": [
        "-y",
        "@fairseal/mcp-server"
      ],
      "env": {
        "FAIRSEAL_API_KEY": "your-value",
        "FAIRSEAL_API_URL": "your-value",
        "FAIRSEAL_NOTARY_API_KEY": "your-value",
        "FAIRSEAL_ANCHOR_API_KEY": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "fairseal": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@fairseal/mcp-server"
      ],
      "env": {
        "FAIRSEAL_API_KEY": "your-value",
        "FAIRSEAL_API_URL": "your-value",
        "FAIRSEAL_NOTARY_API_KEY": "your-value",
        "FAIRSEAL_ANCHOR_API_KEY": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.

Your choice stays on this device in a cookie; no account needed.

Values you fill in

  • FAIRSEAL_API_KEY secret env
    API key for gated tools (fairseal_entropy, fairseal_stats, fairseal_rng_generate, fairseal_notarize_decision, fairseal_anchor_submit). Key prefix: fsn_. Without a key these tools return 401; free too…
  • FAIRSEAL_API_URL env
    Upstream API base URL (default https://api.fairseal.io).
  • FAIRSEAL_NOTARY_API_KEY secret env
    Key override for the notary service only (POST /v1/notarize). Falls back to FAIRSEAL_API_KEY if not set. Key prefix: fsn_.
  • FAIRSEAL_ANCHOR_API_KEY secret env
    Key override for Anchor API v2 only (POST /v2/anchor). Falls back to FAIRSEAL_API_KEY if not set. Key prefix: anck_.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified against the domain fairseal.io (the registry checks domain ownership)

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • – Not applicable

    Endpoint responds

    This one runs on your computer; there is no internet endpoint

  • – Not applicable

    Sign-in with OAuth

    Runs on your computer and uses local settings instead

  • … Not checked yet

    No hidden instructions in tool descriptions

    Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Otheri

  • More stars than 0% of the other 32691 servers in this category
  • Published to the registry more recently than 51% of the other 32691 servers in this category
  • Basic checks equal to or better than 100% of the other 32691 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is Fairseal MCP safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: FAIRSEAL_API_KEY, FAIRSEAL_NOTARY_API_KEY, FAIRSEAL_ANCHOR_API_KEY

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed –, and the latest version (0.2.4) reached the registry 38 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.

What can I use instead?

In the same category: Spec Driven Development, Remote Desktop Commander, Dialyne

Alternatives

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Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

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Runs on your computer★ 440MITUpdated 14 months ago
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Remote Desktop Commander

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Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.

Runs in the cloud★ 211Updated 2 days ago
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Dialyne

by dialyne

Real phone calls in France for AI agents: dial +33 numbers, menus, hold, AI disclosure.

Runs in the cloudUpdated today
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README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

Fairseal 🦭

Provably fair selections for games, loot boxes, and any randomized allocation.

Fairseal creates verifiable receipts (CSRs) proving that a selection was committed before the outcome was knowable. Every loot drop, gacha pull, and randomized selection — independently verifiable, trustlessly.


Try It Now

npx @fairseal/commit

One command. A verifiable gacha pull in your terminal. No setup.

Quick Start

npm install @fairseal/commit
import { createCommitment, resolveCommitment, createReceipt, verifyReceipt } from '@fairseal/commit';

// 1. Lock your loot table BEFORE the outcome is knowable const commitment = createCommitment({ rule: JSON.stringify(LOOT_TABLE), inputs: [playerId, pullNumber.toString()], revealAfter: 10, });

// 2. Resolve with verifiable entropy from drand const resolution = await resolveCommitment(commitment);

// 3. Your algorithm + verifiable entropy = provably fair drop const drop = yourWeightedPull(LOOT_TABLE, resolution.beaconRandomness);

// 4. Package as a receipt anyone can verify const receipt = createReceipt(commitment, resolution); const proof = await verifyReceipt(receipt); // ✅ PARTIAL

How It Works

  1. Commit — Lock your drop table + player ID into a hash before the randomness exists
  2. Entropy — Wait for a public drand beacon round (Cloudflare + Protocol Labs)
  3. Resolve — Derive the selection from beacon entropy + your committed rule
  4. Verify — Anyone can re-run every step. drand beacon signatures are BLS12-381-verified; FairSeal receipt signatures use EIP-191 (secp256k1) / Ed25519 — receipts are never BLS-signed. No trust required.

Performance

OperationTime
Commitment creation0.006ms (170,000+/sec)
Beacon fetch~200ms
drand beacon verification (BLS12-381)~150ms
Receipt size0.9 KB

Client-side. No server. No account. No fees for PARTIAL verification.

Packages

PackageDescription
@fairseal/gameGame API for RGS studios. Slots, gacha, loot boxes. (v0.1 ALPHA)
@fairseal/commitCommitted selection receipts. Core library.
@fairseal/coreCryptographic primitives, signing, Merkle trees.
@fairseal/verifyIndependent receipt verification.
@fairseal/mcp-serverMCP server for AI agents. Verifiable entropy, provably-fair games, cryptographic receipt verification via Model Context Protocol.

Use Cases

ScenarioHow
Gacha / loot boxEvery pull has a receipt. Players verify drops match published rates.
Boss loot dropsDrop table committed per encounter. No ninja-nerfing.
MatchmakingPairing algorithm committed. Players verify no favoritism.
Tournament bracketsSeeding provably random, not rigged.
NFT mint orderQueue provably fair — no insider front-running.
Slot machinesSeed Commitment Model — verifiable spins, no nonce chain.

Result Notarization vs. Activity Receipts

Most "agent receipts" today are activity receipts: the platform logs what an agent did, and you trust whoever wrote the log. Fairseal receipts are result notarization — a different trust model:

Activity receipts (platform logs)Fairseal result notarization
Who do you trust?The operator writing the logNo one — receipts verify offline
What is proven?That an action was recordedThat a result was committed before the outcome was knowable
Time proofServer timestamp (operator-controlled)External anchor on Base (independently checkable)
Tamper evidenceDepends on log integrityHash-anchored; any modification breaks verification

Related standards: payment-authorization protocols like Google/Mastercard AP2 (mandates), Visa TAP, and OpenAI/Stripe ACP prove that an agent *may* act and *who* it is. Fairseal proves *what happened* — that a result was committed and hasn't been altered since. Fairseal settles micropayments over Coinbase's x402 and does not implement AP2/TAP/ACP; the layers are complementary.

Links

Listings

License

MIT — Fairseal

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