AgentAPI

A curated directory of APIs designed for AI agents. Machine-readable. MCP-compatible. Agent-accessible.

Website: https://agentapihub.com
Billing API: https://api.agentapihub.com
Docs: https://api.agentapihub.com/api/docs

x402 Pay-Per-Use Billing

AgentAPI supports x402 — a payment protocol that lets AI agents pay for API calls with USDC on Base. No API keys required.

How It Works

1. Agent calls API endpoint (e.g., /api/gemini/chat/completions)
2. Server returns 402 Payment Required with price + wallet address
3. Agent sends USDC payment on Base chain
4. Agent retries with payment proof in header
5. Server verifies payment, proxies request, returns response

Example Flow

# 1. Initial request returns 402
curl https://api.agentapihub.com/api/gemini/chat/completions \
  -H "Content-Type: application/json" \
  -d '{"model":"gemini-2.0-flash","messages":[{"role":"user","content":"Hello"}]}'

# Response: 402 Payment Required
# {
#   "price": "0.001",
#   "currency": "USDC",
#   "chain": "base",
#   "recipient": "0xcCb92A101347406ed140b18C4Ed27276844CD9D7",
#   "paymentId": "pay_abc123"
# }

# 2. Agent pays on Base, retries with proof
curl https://api.agentapihub.com/api/gemini/chat/completions \
  -H "Content-Type: application/json" \
  -H "X-Payment-Proof: 0x..." \
  -d '{"model":"gemini-2.0-flash","messages":[{"role":"user","content":"Hello"}]}'

Available x402 APIs

API	Endpoint	Price
Gemini Chat	/api/gemini/chat/completions	~$0.001/req
Gemini Embeddings	/api/gemini/embeddings	~$0.0005/req

Why x402?

• No API keys — Agents self-provision access
• Pay-per-use — No subscriptions, no minimums
• Crypto-native — USDC on Base (fast, cheap txns)
• Agent-friendly — Programmatic payments without human bottleneck

Quick Search

By Category

Category	APIs	Example
Search	Brave, Serper, Exa, Tavily, Perplexity	Web search with AI summaries
AI & ML	OpenAI, Claude, Gemini, Groq, Replicate	LLM inference, image gen
Communication	Resend, Twilio, Slack, Discord, Telegram	Email, SMS, messaging
Database	Supabase, Pinecone, Qdrant, Neon, Upstash	SQL, vectors, KV store
Payments	Stripe, Lemon Squeezy, PayPal	Payment processing
Scraping	Firecrawl, Browserbase, Apify	Web scraping, automation
Developer	GitHub, Vercel, Linear, Sentry	Code, deploy, issues
Productivity	Notion, Google Calendar, Todoist	Tasks, scheduling

MCP-Compatible APIs

All 50+ APIs in the directory are MCP-compatible. Filter with ?mcp=true.

API Access

JSON Endpoint

# Fetch all APIs
curl https://agentapihub.com/api/v1/apis

# Search by capability
curl "https://agentapihub.com/api/v1/apis?q=send+email&mcp=true"

# Filter by category
curl "https://agentapihub.com/api/v1/apis?category=ai"

Response Format

{
  "id": "resend",
  "name": "Resend",
  "description": "Modern email API for developers",
  "category": "communication",
  "provider": "Resend",
  "docs": "https://resend.com/docs",
  "auth": "api_key",
  "pricing": "freemium",
  "pricingDetails": "3,000 free/mo, then $20/mo",
  "rateLimit": "10 req/sec",
  "mcpCompatible": true,
  "examplePrompt": "Send an email notification using Resend",
  "latency": "fast",
  "reliability": 99.9,
  "tags": ["email", "transactional", "notifications"]
}

Top APIs by Category

Search

• Brave Search - Privacy-focused, 2k free/mo
• Exa - Neural/semantic search for AI
• Tavily - Built specifically for AI agents

AI & ML

• OpenAI - GPT-4, DALL-E, Whisper
• Anthropic Claude - Best for reasoning/coding
• Groq - Fastest inference (500+ tok/sec)

Communication

• Resend - Simple email API, 3k free/mo
• Twilio - SMS/voice, industry standard
• Slack/Discord/Telegram - Team messaging

Database

• Supabase - Postgres + auth + storage
• Pinecone/Qdrant - Vector DBs for RAG
• Upstash - Serverless Redis

Usage Examples

# Find an API for sending emails
Search AgentAPI for "email" → Returns Resend, SendGrid, Twilio

# Find vector databases for RAG
Search AgentAPI for "vector embeddings" → Returns Pinecone, Qdrant, Weaviate

# Find fast LLM inference
Search AgentAPI for category "ai" + filter by latency → Returns Groq, Gemini Flash

Contributing

Submit new APIs at https://agentapihub.com (Submit API link in footer).

Built By

GizmoLab (@gizmolab_) — gizmolab.io