specter-skills MCP Server

specter-skills

Build your game backend by talking to Claude.

specter-skills teaches Claude everything about Specter — the game backend platform — so you can add player accounts, an in-game economy, daily quests, leaderboards, tournaments, battle passes, and real-time multiplayer to your game in plain English, and get correct, working code plus the ability to configure your backend without ever opening the dashboard.

No SDK to learn. No API docs to read. Install it, then ask.

You:    "Add Specter to my game — silent login, a coins wallet, and a daily
         quest 'play 3 matches' that rewards 100 coins."
Claude: ...writes the integration code, sets up the quest in your backend, done.

Contents

• What's inside
• Quickstart
• Installation
• The skills
• The MCP server · Setup · Sign in · Tools · Configuration
• Things to ask Claude
• Checking the version & updating
• Requirements
• Troubleshooting

What's inside

This one package ships two halves of the same product:

Skills work in Claude Code, Claude Desktop, the Claude Agent SDK, and any other skills-aware host. The MCP server works in any MCP-compatible host (Claude Desktop, Claude Code, …).

Quickstart

1. Install the skills in your game project:

npx specter-skills init

2. Get your API key from console.specterapp.xyz (Project → API Keys).

3. Ask Claude to build something:

"Add Specter email login and a gem currency to my Unity game."

The right skill activates automatically and Claude writes the integration. That's it.

💡 Want Claude to also set up the backend for you (create currencies, quests, leaderboards)? Add the MCP server and ask "create a gems currency and a daily login quest in my Specter project."

Installation

# Interactive — choose skills and where to install them
npx specter-skills init

# Install everything into this project's .claude/skills/
npx specter-skills install

# Install specific skills
npx specter-skills install specter specter-economy

# Install globally (available in all your projects)
npx specter-skills install --global

# Install into a custom directory (Agent SDK / other hosts)
npx specter-skills install --dir ./skills

Skills are copied into .claude/skills/ (project) or ~/.claude/skills/ (global). They're plain files you can commit to your repo.

The skills

Each skill has a concise guide plus per-endpoint references (request fields, response examples) generated directly from Specter's API, and ready-to-paste JavaScript / Unity examples where useful — so the code Claude writes stays accurate.

The MCP server

The same package ships an MCP server, specter-mcp, that lets Claude inspect and configure a Specter backend directly. The skills teach Claude the API; the MCP server lets it use the API.

"What currencies does my project have?" · "Is my setup working?" · "Create a gems currency and a daily quest that rewards 100 coins."

Setup

The easy way — npx specter-skills init offers to set this up for you (it writes the config, no JSON editing). Or run it any time:

# Claude Desktop
npx specter-skills mcp

# Claude Code (registers it for all your projects)
npx specter-skills mcp --code

Then restart your MCP host and the specter tools appear. (Claude Desktop and Claude Code are different apps with separate configs — pick the one you actually use.)

{
  "mcpServers": {
    "specter": {
      "command": "npx",
      "args": ["-y", "-p", "specter-skills", "specter-mcp"],
      "env": {
        "SPECTER_ENV": "staging",
        "SPECTER_ALLOW_MUTATIONS": "true"
      }
    }
  }
}

Read-only tools work immediately; creating things needs a one-time sign-in — no api-key or project ID to configure.

Signing in (no password needed)

To create anything, Claude needs to act as you — so you authorize it once through your browser. The first time it's needed, Claude runs the specter_login tool (or run it yourself in a terminal):

npx -y -p specter-skills specter-mcp login

What happens:

1. Your browser opens the Specter dashboard.
2. You sign in however you normally do — email/password, Google, or Apple.
3. You approve a consent screen ("Allow specter-mcp to manage your projects").
4. Done — a revocable token is saved locally (~/.specter/credentials.json). You stay signed in.

Your password and social credentials never touch the tool or Claude. Revoke access anytime from the dashboard. Manage the session with specter-mcp whoami and specter-mcp logout.

ℹ️ Run specter-mcp commands from any folder except the specter-skills source folder itself (npx gets confused there).

Tools

Read-only — always available, safe to run:

Read tools use your browser sign-in (run specter_login once) — no separate api-key to configure.

Client / runtime — act as a sandboxed test player to exercise the game-facing /v2/client API and prove your config works:

Mutating — opt-in (SPECTER_ALLOW_MUTATIONS=true), gated behind your confirmation:

The achievement tools resolve friendly names for you — pass event as an event slug/name, rewards as [{currency:"gems", quantity:50}] (or item/bundle/marker), and the tool resolves them to the right ids. Creating an achievement does not make it live — call specter_schedule_achievement to activate it.

Mutating tools change live game configuration, so they're flagged non-read-only and your MCP host asks for confirmation before each one. Point them at a staging project first.

Your project is auto-detected from your sign-in — there's no project ID to look up. (Only set SPECTER_PROJECT_ID if your organisation has several projects and you want to pin one.)

Configuration

All configuration is via env vars in your MCP host config:

Things to ask Claude

Once installed, just describe what you want — the right skill (and MCP tool) kicks in automatically:

• "Add silent device login and a coins wallet to my game."
• "Set up a daily quest: play 5 matches → reward 200 coins. Create it in my Specter project and give me the client code."
• "Create a premium gem currency and a starter store that sells a 'Sword' item for 100 gems."
• "Add a weekly leaderboard with top-10 prize distribution."
• "Build a battle pass with 30 tiers."
• "Add skill-based matchmaking with parties — show me the WebSocket events to handle."
• "Why am I getting a 429 from Specter?"
• "Is my Specter project set up correctly?"

Checking the version & updating

# Latest version published on npm
npm view specter-skills version

# Which skills you have installed (and their versions)
npx specter-skills list

# Update your installed skills to the latest
npx specter-skills update

npx caches packages for ~24h. If update pulls an old version, force the latest with npx specter-skills@latest update. The MCP server (npx … specter-mcp) always fetches the latest published version the same way.

Requirements

• Node.js 18+
• A Specter project + API key (console.specterapp.xyz)
• A skills-aware Claude host (Claude Code, Claude Desktop, or the Agent SDK) for the skills; an MCP-compatible host for the server

Troubleshooting

Links

• 🎮 Dashboard: console.specterapp.xyz
• 📦 npm: npmjs.com/package/specter-skills

npm version patch        # or minor / major
npm run generate         # refresh references
npm publish --access public