AI plugin marketplace. SDK, gateway & developer tools for building function-calling plugins. OpenAPI compatible, multi-language support, Vercel edge deployment. Build chat plugins, AI tools & extensions. Primary use in cryptocurrency, DeFI, crypto trading, and blockchain analytics. Compatible with ERC-8004 agents.

User: "What's the price of ETH?"
         │
         ▼
┌─────────────────────────────────────────────────────────┐
│  SperaxOS discovers plugin from plugin.delivery index   │
│  AI generates function call: getPrice(coin: "ethereum") │
│  Gateway routes request to CoinGecko API                │
│  Response rendered in chat (JSON, Markdown, or UI)      │
└─────────────────────────────────────────────────────────┘
         │
         ▼
AI: "ETH is currently trading at $3,450..."

SperaxOS supports 4 distinct plugin types, each optimized for different use cases:

Returns JSON data that the AI formats into natural language.

{
  "ui": {
    "mode": "default"
  }
}

Use when: You have an API that returns structured data and want the AI to explain results conversationally.

Returns pre-formatted Markdown that displays directly in chat.

{
  "ui": {
    "mode": "markdown"
  }
}

Use when: You want full control over formatting — tables, code blocks, headers, etc.

Embeds a full React/HTML application in an iframe within the chat.

{
  "ui": {
    "mode": "standalone",
    "url": "https://your-plugin.com/ui",
    "height": 400
  }
}

Use when: You need rich interactivity — charts, forms, dashboards, embedded apps.

💡 Standalone plugins are SperaxOS's superpower — they enable experiences beyond what ChatGPT plugins can do.

Auto-generated from an OpenAPI 3.x specification. No custom code needed.

{
  "openapi": "https://your-api.com/openapi.json"
}

Use when: You already have an OpenAPI spec for your API.

Artifacts are rich interactive content that plugins can render directly in chat. Unlike plain text responses, artifacts can include:

• 📊 Charts & Visualizations (Chart.js, Recharts, D3)
• 📝 Interactive Forms (Input fields, buttons, selectors)
• 🎮 Mini Applications (Games, calculators, tools)
• 📄 Rich Documents (Formatted reports, tables)

Render raw HTML directly:

// In your plugin API response
return {
  type: 'html',
  content: `
    <div style="padding: 20px;">
      <h2>Price Alert</h2>
      <p>ETH crossed $3,500!</p>
    </div>
  `
};

Render React components (standalone plugins):

// ui/page.tsx
export default function PriceChart({ data }) {
  return (
    <div className="p-4">
      <LineChart data={data}>
        <Line dataKey="price" stroke="#22c55e" />
      </LineChart>
    </div>
  );
}

Embed external content:

{
  "ui": {
    "mode": "standalone",
    "url": "https://tradingview.com/chart/?symbol=BTCUSD",
    "height": 500
  }
}

Standalone plugins can trigger additional function calls:

import { speraxOS } from '@sperax/plugin-sdk/client';

// Trigger a new function call from your UI
speraxOS.triggerFunctionCall({
  name: 'getTokenDetails',
  arguments: { token: 'ETH' }
});

Get started fast with our official templates:

# Clone template to new directory
cp -r templates/standalone my-plugin
cd my-plugin

# Install dependencies
bun install

# Start development
bun dev

templates/standalone/
├── public/
│   └── manifest.json    # Plugin manifest
├── src/
│   ├── api/            # API endpoints
│   │   └── index.ts    # Main handler
│   └── ui/             # React UI (standalone only)
│       └── page.tsx    # UI component
├── package.json
└── README.md

The SDK is not published to the npm registry yet. Install it from a clone of this repository:

git clone https://github.com/nirholas/plugin.delivery.git
cd plugin.delivery
pnpm install

@sperax/plugin-sdk and @sperax/chat-plugins-gateway then resolve as workspace packages (see pnpm-workspace.yaml).

{
  "$schema": "https://plugin.delivery/schema.json",
  "identifier": "my-crypto-plugin",
  "api": [
    {
      "name": "getPrice",
      "description": "Get cryptocurrency price",
      "url": "https://my-plugin.vercel.app/api/price",
      "parameters": {
        "type": "object",
        "properties": {
          "coin": {
            "type": "string",
            "description": "Coin ID (e.g., bitcoin, ethereum)"
          }
        },
        "required": ["coin"]
      }
    }
  ],
  "meta": {
    "title": "My Crypto Plugin",
    "description": "Get real-time crypto prices",
    "avatar": "🪙",
    "tags": ["crypto", "prices"]
  }
}

// api/price.ts
export default async function handler(req: Request) {
  const { coin } = await req.json();
  
  const res = await fetch(
    `https://api.coingecko.com/api/v3/simple/price?ids=${coin}&vs_currencies=usd`
  );
  const data = await res.json();
  
  return Response.json({
    coin,
    price: data[coin]?.usd,
    timestamp: new Date().toISOString()
  });
}

# Deploy to Vercel
vercel --prod

# Add to plugin index (submit PR or use Plugin Store)

• Bun 1.0+ (recommended) or Node.js 18+
• Git

# Clone
git clone https://github.com/nirholas/plugin.delivery.git
cd plugins

# Install
bun install

# Dev server
bun dev

⚠️ CRITICAL: You MUST create both files or the build will fail:

1. src/[plugin-name].json - Plugin definition
2. locales/[plugin-name].en-US.json - Locale file (REQUIRED)

1. Create plugin definition in src/[plugin-name].json:

{
  "author": "Your Name",
  "createdAt": "2025-12-29",
  "homepage": "https://example.com",
  "identifier": "my-plugin",
  "manifest": "https://plugin.delivery/my-plugin/manifest.json",
  "meta": {
    "avatar": "🔌",
    "description": "What your plugin does",
    "tags": ["tag1", "tag2"],
    "title": "My Plugin",
    "category": "stocks-finance"
  },
  "schemaVersion": 1
}

2. Create locale file in locales/[plugin-name].en-US.json (REQUIRED):

{
  "meta": {
    "title": "My Plugin",
    "description": "What your plugin does",
    "tags": ["tag1", "tag2"]
  }
}

3. Create manifest in public/[plugin-name]/manifest.json:

{
  "$schema": "https://plugin.delivery/schema.json",
  "identifier": "my-plugin",
  "api": [
    {
      "url": "https://plugin.delivery/api/my-plugin/endpoint",
      "name": "myFunction",
      "description": "What this function does",
      "parameters": {
        "type": "object",
        "properties": {
          "param": { "type": "string", "description": "Parameter description" }
        },
        "required": ["param"]
      }
    }
  ],
  "meta": {
    "avatar": "🔌",
    "title": "My Plugin",
    "description": "What your plugin does"
  },
  "version": "1"
}

4. Create API endpoints in api/[plugin-name]/[endpoint].ts

5. ⚠️ REQUIRED: Create locale file locales/[plugin-name].en-US.json:

{
  "meta": {
    "title": "Your Plugin Title",
    "description": "Your plugin description",
    "tags": ["your", "tags"]
  }
}

BUILD WILL FAIL without this file. Copy title, description, and tags from your plugin's meta object.

6. Run format (generates i18n translations for 18 languages):

# Set OpenAI API key (required for i18n generation)
export OPENAI_API_KEY=sk-your-key-here

# Generate translations (creates all locale files from en-US)
bun run format

7. Build the plugin index:

bun run build

8. Commit and push:

git add src/[plugin-name].json locales/[plugin-name].*.json
git commit -m "feat: add [plugin-name] plugin"
git push

⚠️ Important: Always run bun run format before bun run build when adding new plugins. The format command uses OpenAI to generate translations for all 18 supported languages.

plugins/
├── packages/
│   ├── sdk/              # @sperax/plugin-sdk
│   └── gateway/          # @sperax/chat-plugins-gateway
├── templates/            # Starter templates
│   ├── basic/
│   ├── default/
│   ├── markdown/
│   ├── openapi/
│   ├── settings/
│   └── standalone/
├── public/               # Static files (auto-generated)
│   ├── index.json        # Plugin registry
│   └── openai/           # OpenAPI manifests
├── src/                  # Plugin definitions
├── locales/              # i18n translations
├── docs/                 # Documentation
└── api/                  # Serverless functions

Both packages live in this repository and are not published to the npm registry yet.

import { 
  pluginManifestSchema,
  createPluginResponse,
  PluginError 
} from '@sperax/plugin-sdk';

// Client-side (in standalone UI)
import { speraxOS } from '@sperax/plugin-sdk/client';

The Plugin Gateway securely routes function calls from SperaxOS to plugin APIs:

SperaxOS → Gateway → Plugin API
              │
              ├── Auth injection
              ├── Rate limiting
              ├── Request logging
              └── Response transform

# Clone gateway
cd packages/gateway

# Deploy
vercel --prod

# Set in SperaxOS
PLUGINS_GATEWAY_URL=https://your-gateway.vercel.app

We welcome contributions! See CONTRIBUTING.md.

1. Option A: Open a Plugin Submission issue
2. Option B: Submit a PR adding your plugin to src/

• ✅ Valid manifest with working endpoints
• ✅ Tested in SperaxOS
• ✅ No API key required (or documented)
• ✅ en-US locale at minimum

All rights reserved. See LICENSE.

Plugin Delivery is deployed and accessible over HTTP via MCP Streamable HTTP transport — no local installation required.

Endpoint:

https://modelcontextprotocol.name/mcp/plugin-delivery

Add to your MCP client configuration (Claude Desktop, Cursor, SperaxOS, etc.):

{
  "mcpServers": {
    "plugin-delivery": {
      "type": "http",
      "url": "https://modelcontextprotocol.name/mcp/plugin-delivery"
    }
  }
}

Search AI plugins:

curl -X POST https://modelcontextprotocol.name/mcp/plugin-delivery \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"search_plugins","arguments":{"query":"weather"}}}'

Platform info:

curl -X POST https://modelcontextprotocol.name/mcp/plugin-delivery \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"get_plugin_info","arguments":{}}}'

curl -X POST https://modelcontextprotocol.name/mcp/plugin-delivery \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

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• All 27 MCP servers — See the full catalog at modelcontextprotocol.name

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