Semantic API MCP Server

An MCP (Model Context Protocol) server that lets Claude, ChatGPT, and other LLM agents search and discover APIs using natural language via Semantic API. 573 providers, 2,930+ capabilities — the largest agent-optimized API catalog available.

Ask for any API capability in plain English and get back endpoint details, parameters, auth info, and code snippets. Browse the interactive catalog at semanticapi.dev/catalog — no signup required.

✨ Auto-Discover & Auto-Heal

Auto-Discover: Ask for any API — even ones not in the catalog. The server automatically finds docs, generates a provider config, and returns endpoint details. Your agent never hits a dead end.

Auto-Heal: If an API's config goes stale (endpoints change, versions update), the server detects the failure, re-discovers from current docs, and retries — all in a single tool call. Zero maintenance.

Key features: Key Vault for secure API key storage • 100% auth metadata coverage • Auto-discover any API • Auto-heal stale configs • 7 MCP tools

Install

pip install semanticapi-mcp

Or run directly with uvx:

uvx semanticapi-mcp

Configuration

Get an API Key

Sign up at semanticapi.dev to get your API key.

Environment Variables

Variable	Required	Default	Description
SEMANTIC_API_KEY	Yes	—	Your Semantic API key
SEMANTIC_API_URL	No	https://semanticapi.dev	API base URL override

Claude Desktop

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

{
  "mcpServers": {
    "semanticapi": {
      "command": "uvx",
      "args": ["semanticapi-mcp"],
      "env": {
        "SEMANTIC_API_KEY": "your-api-key-here"
      }
    }
  }
}

Or if installed with pip:

{
  "mcpServers": {
    "semanticapi": {
      "command": "semanticapi-mcp",
      "env": {
        "SEMANTIC_API_KEY": "your-api-key-here"
      }
    }
  }
}

Tools

semantic_query

Search for an API capability using natural language.

Inputs:

• query (string, required) — What you want to do, e.g. "send an email with Gmail"
• auto_discover (boolean, optional, default: true) — Auto-discover new APIs if needed

Example: "Find me an API to convert currencies in real-time"

semantic_discover

Deep discovery of a specific provider/API by name and intent.

Inputs:

• provider_name (string, required) — API provider name, e.g. "stripe", "twilio"
• user_intent (string, optional) — What you want to do with this API

Example: Discover Stripe's capabilities for "process a refund"

semantic_discover_url

Analyze any API from its documentation URL.

Inputs:

• url (string, required) — URL of the API documentation
• user_intent (string, optional) — What you want to do with this API

Example: Analyze https://docs.example.com/api to generate a provider config

semantic_catalog

Browse and search the provider catalog. No API key required.

Inputs:

• page (integer, optional, default: 1) — Page number
• auth_type (string, optional) — Filter by auth type: "bearer", "apikey", "oauth2", "none"
• category (string, optional) — Filter by category: "payments", "ai", "communication", etc.
• search (string, optional) — Search by name or description
• free_only (boolean, optional) — Only show providers with a free tier

Example output:

📦 Stripe (stripe)
   Online payment processing platform
   Auth: bearer | Free tier: no | Capabilities: 12

📦 Open-Meteo (open-meteo)
   Free weather API, no key required
   Auth: none | Free tier: yes | Capabilities: 5

Page 1/58 (573 total providers)

semantic_provider_detail

Get full details for a specific provider including all capabilities. No API key required.

Inputs:

• provider_id (string, required) — Provider identifier, e.g. "stripe", "open-meteo"

Example output:

📦 Stripe (stripe)
   Online payment processing platform
   Base URL: https://api.stripe.com
   Auth: bearer
   Signup: https://dashboard.stripe.com/register
   Free tier: no

   Capabilities:
   ├─ create-charge: Create a new charge
   │  POST /v1/charges
   └─ list-customers: List all customers
      GET /v1/customers

semantic_catalog_stats

Get public statistics about the catalog. No API key required.

Example output:

📊 Semantic API Catalog Stats
   Total Providers: 573
   Total Capabilities: 2,930
   Categories: 24

semantic_categories

List all available provider categories. No API key required.

Example output:

📂 Provider Categories

   • payments (8 providers)
   • ai (6 providers)
   • communication (5 providers)
   • weather (3 providers)

Related

• Semantic API — The hosted API service
• semanticapi-engine — Open source engine (AGPL-3.0)
• semantic-api-skill — Agent framework skill package
• CLI Tool — Command-line interface (pip install semanticapi-cli)

License

MIT