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x402 API Live Demo

Interactive demo of the Munchausen Lab x402 API: pay-per-call AI analytics with USDC micropayments on Base. Try free endpoints live.

Pay-per-call AI analytics over the x402 protocol — USDC micropayments on Base. No signup, no KYC, no API keys.

API discovery endpoint → What is x402?

Try it right now (free)

These buttons send real requests to the production API. No wallet or USDC needed.

GET

/api/free

$0.00 live prices

Real-time BTC / ETH / SOL prices. Rate limit: 5 calls/min.


        

    


    

        

            GET
            
/api/demo

            $0.00
            AI sample
        

        
Free sample AI analysis: real-time prices plus a templated market breakdown. Unlimited.

        
        

            

            

        

    


    
Paid endpoints (x402 / USDC on Base)

    
Call any paid endpoint and it answers 402 Payment Required with an exact price. An x402-enabled client pays from its wallet and retries — you receive the data. No accounts anywhere in the loop.


    

        

            GET
            
/api/quote

            $0.01
        

        
Market quote with 24h change. Example:

        
curl "https://api.munchausen.site/api/quote?symbol=BTC"

    


    

        

            GET
            
/api/analyze

            $0.05
        

        
LLM-powered market analysis (sentiment, levels, risks) via OpenRouter.

        
curl "https://api.munchausen.site/api/analyze?topic=DeFi"

    


    

        

            POST
            
/api/report

            $0.25
        

        
Full LLM research report (150+ lines).

        
curl -X POST https://api.munchausen.site/api/report \
  -H "Content-Type: application/json" \
  -d '{"query": "DeFi yield opportunities"}'

    


    
How the x402 flow works

    
    
        
  1. Your agent calls a paid endpoint — no signup, no key.
    2. 
        
  2. The server replies 402 with payment requirements (amount, address, network).
    3. 
        
  3. The client signs a USDC transfer on Base and retries with the proof header.
    4. 
        
  4. Data comes back. Total overhead: one extra round-trip.
    5. 
    


    
Discovery for agents

    

        

            
            
Machine-readable discovery

        

        
GET / returns full endpoint catalog with pricing. /agent.json and /llms.txt follow agent-discovery conventions. /health for uptime checks.

        
curl https://api.munchausen.site/