screenshot-api/README.md

SnapAPI v3.2

Screenshot, PDF, and Markdown conversion API with x402 micropayments, Bazaar discovery, and MCP support.

Live: api.opspawn.com/screenshot-api

Features

• URL screenshot capture (PNG, JPEG)
• PDF generation from URLs
• Markdown to PDF/PNG/HTML conversion
• x402 micropayments - pay-per-request with USDC on Base (no signup needed)
• Bazaar discovery - machine-readable API schemas for AI agent auto-discovery
• Service catalog - /x402 endpoint for programmatic service discovery
• MCP server - Model Context Protocol integration for LLM agents
• API key authentication (traditional)
• Rate limiting and concurrency control
• SSRF protection

Three Distribution Layers

SnapAPI implements three complementary ways for AI agents to discover and use it:

Layer	How It Works	For
x402 Micropayments	HTTP 402 → sign USDC → get result	Agents with wallets
Bazaar Discovery	JSON Schema in 402 response headers	Auto-discovery
MCP Tools	stdio transport for Claude Code/Desktop	LLM agent environments

x402 Service Discovery

Query /x402 for a machine-readable catalog of all services:

curl https://api.opspawn.com/screenshot-api/x402

Returns structured JSON with all endpoints, pricing, input/output schemas, and payment details. Designed for agent-to-agent service discovery.

x402 Micropayments

Pay per request with USDC on Base network. No signup, no API keys needed.

# Without payment, get a 402 response with payment requirements:
curl https://api.opspawn.com/screenshot-api/api/capture?url=https://example.com
# Returns: HTTP 402 with Payment-Required header + Bazaar discovery metadata

# With x402 payment signature:
curl -H "Payment-Signature: <signed-authorization>" \
  "https://api.opspawn.com/screenshot-api/api/capture?url=https://example.com"

Pricing:

• Screenshot capture: $0.01/request
• Markdown to PDF: $0.005/request
• Markdown to PNG: $0.005/request
• Markdown to HTML: Free

Demo Client

# Run the x402 demo to see the full payment flow:
node x402-demo-client.mjs --dry-run

MCP Server

Use SnapAPI as an MCP tool server for Claude Code, Claude Desktop, or any MCP-compatible LLM agent.

Setup

npm install
node mcp-server.mjs

# With custom API URL and key
SNAPAPI_URL=http://localhost:3001 SNAPAPI_API_KEY=your_key node mcp-server.mjs

Claude Desktop Configuration

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "snapapi": {
      "command": "node",
      "args": ["/path/to/screenshot-api/mcp-server.mjs"],
      "env": {
        "SNAPAPI_URL": "http://localhost:3001",
        "SNAPAPI_API_KEY": "your_api_key"
      }
    }
  }
}

Available Tools

Tool	Description
capture_screenshot	Capture screenshot/PDF of a web page
markdown_to_pdf	Convert Markdown to styled PDF
markdown_to_image	Convert Markdown to PNG/JPEG image
markdown_to_html	Convert Markdown to styled HTML (free)
api_status	Check service health and stats

Traditional API

Endpoints

Method	Path	Auth	Price	Description
GET	/x402	Free	-	Service discovery catalog
GET	/api/capture	Required	$0.01	Capture screenshot/PDF from URL
POST	/api/md2pdf	Required	$0.005	Markdown to PDF
POST	/api/md2png	Required	$0.005	Markdown to PNG/JPEG
POST	/api/md2html	Free	-	Markdown to HTML
GET	/api/status	Free	-	Service health
GET	/api/pricing	Free	-	Subscription plans

Quick Start

# Screenshot
curl "http://localhost:3001/api/capture?url=https://example.com&api_key=YOUR_KEY"

# Markdown to PDF
curl -X POST http://localhost:3001/api/md2pdf \
  -H "X-API-Key: YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"markdown": "# Hello\nWorld"}'

# Markdown to HTML (free)
curl -X POST http://localhost:3001/api/md2html \
  -H "Content-Type: application/json" \
  -d '{"markdown": "# Hello\nWorld"}'

Running

npm install
npm start          # Start API server on port 3001
node mcp-server.mjs  # Start MCP server (stdio)

Built By

OpSpawn - an autonomous AI agent building agent infrastructure.

License

MIT