yc-mcp

MCP server for Y Combinator company data. Use with Claude Desktop, Claude Code, or custom AI agents.

Quick Start

Claude Desktop

Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "yc": {
      "command": "npx",
      "args": ["-y", "yc-mcp"]
    }
  }
}

Restart Claude Desktop. You now have 6 tools for exploring YC companies.

Claude Code

Add to your project's .mcp.json:

{
  "mcpServers": {
    "yc": {
      "command": "npx",
      "args": ["-y", "yc-mcp"]
    }
  }
}

Tools

| Tool | Description | |------|-------------| | list_yc_batch | List companies in a batch (W26, S25, winter-2026, etc.) | | search_yc_companies | Search by name, industry, tag, or description | | get_yc_company | Get company details + founders + LinkedIn URLs | | list_yc_industries | List all industries with company counts | | list_yc_tags | List all tags with company counts | | prefetch_yc_batch | Warm the founder cache for a batch (background) |

Example Usage

Once configured, ask Claude:

• "List YC companies from Winter 2026"
• "Search for AI companies in the latest YC batch"
• "Get details about Stripe including founders"
• "What industries are most common in YC?"
• "Find YC companies working on developer tools"

Tool Parameters

list_yc_batch

{
  "batch": "winter-2026",
  "source": "yc-oss"
}

Accepts batch formats: W26, S25, winter-2026, Summer 2025, etc.

search_yc_companies

{
  "query": "AI",
  "industry": "B2B",
  "tag": "Developer Tools",
  "batch": "W26",
  "limit": 20,
  "source": "yc-oss"
}

All parameters are optional. Combine for filtered searches.

get_yc_company

{
  "identifier": "stripe",
  "source": "yc-oss"
}

Returns full company details including founders with LinkedIn URLs.

list_yc_industries / list_yc_tags

{
  "limit": 50,
  "source": "yc-oss"
}

prefetch_yc_batch

{
  "batch": "W26",
  "source": "yc-oss"
}

Pre-fetches founder data for all companies in a batch. Runs in background.

Data Sources

| Source | Description | Pros | Cons | |--------|-------------|------|------| | yc-oss (default) | yc-oss/api | No API keys, reliable | Updated daily | | algolia | YC's Algolia index | Real-time data | Keys may rotate |

Founder Data

Founder information (names, titles, LinkedIn URLs) is scraped from YC company pages on-demand and cached for 1 hour. Use prefetch_yc_batch to warm the cache for faster subsequent lookups.

Development

# Install dependencies
npm install

# Run in development mode
npm run dev

# Build for production
npm run build

# Test with MCP inspector
npm run inspector

Architecture

src/
├── index.ts              # MCP server entry point
├── tools.ts              # Tool definitions & handlers
├── types.ts              # TypeScript interfaces
├── scraper.ts            # Founder data scraper
└── connectors/
    ├── index.ts          # Connector factory
    ├── yc-oss.ts         # yc-oss connector
    └── algolia.ts        # Algolia connector

License

MIT