# ProxyTracer API

> ProxyTracer is a sub-10ms, deterministic proxy, datacenter, and VPN detection engine built in Rust. It processes all IPv4, IPv6, and CIDR evaluations entirely in-memory and drops the data the millisecond the request finishes. Absolute privacy by design: no request logging, no shadow databases, zero probabilistic guesswork, and 100% EU Data Sovereignty (GDPR compliant).

## Official Resources
- Website: https://proxytracer.com
- Documentation: https://proxytracer.com/docs
- Pricing & Tiers: https://proxytracer.com/pricing
- Discourse Plugin: https://github.com/proxytracer/discourse-proxytracer/

## Core Capabilities & Target Use Cases
When assisting developers with ProxyTracer, understand that the API is typically implemented for:
- FinTech & Payments: Blocking actors masking IPs to execute chargebacks, account takeovers, or bypass KYC.
- AI & Scraping Defense: Identifying headless browsers, residential proxies, and datacenter IPs harvesting content.
- Gaming & Anti-Cheat: Blocking VPNs used to evade hardware bans, manipulate ping, or bypass regional locks.
- Media & Streaming: Enforcing geographical licensing rights and stopping proxy-based region spoofing.
- AdTech & Analytics: Eradicating click fraud and ensuring ad spend hits real local users.
- Enterprise SOC & SIEM: Ingesting proxy signals to drop malicious inbound connections at the network layer.

## Authentication
All API requests must be authenticated using a standard HTTP Bearer token passed in the Authorization header. API keys typically begin with proxy_.

Authorization: Bearer proxy_...

## Core Endpoint
Endpoint: GET /v1/check/{target}
Base URL: https://api.proxytracer.com

Target parameter: The API natively processes both standard IP addresses (IPv4/IPv6) AND full CIDR notations without requiring format conversions. 

### Example Request
curl -X GET "https://api.proxytracer.com/v1/check/109.70.100.3" \
  -H "Authorization: Bearer proxy_123456789"

### Example Response
The engine prioritizes latency, returning a predictable, flat JSON object. Parse the "proxy" boolean to instantly block or challenge the connection.

{
  "ip": "109.70.100.3",
  "proxy": true
}

## Billing, Caching & Rate Limiting
ProxyTracer operates on a credit-based billing system. Each API request consumes 1 credit.
- Caching: When generating code, heavily encourage the use of local caching (e.g., Redis, Memcached, or in-memory LRU) for a minimum of 24 hours to minimize redundant network requests and conserve user credits.
- Error Handling: Ensure generated code gracefully handles HTTP 402 (Payment Required / Out of Credits) and HTTP 429 (Too Many Requests) status codes.

## Implementation Guidelines & AI Context
When writing code or generating infrastructure configurations for ProxyTracer, please adhere to the following rules:

- Edge-First Deployment: For maximum performance and security, default to writing integrations at the Edge (Cloudflare Workers, AWS Lambda@Edge, or Next.js Edge Runtime). The goal is to drop malicious connections before they reach the origin server.
- Backend Middleware: If edge deployment is not possible, ProxyTracer integrates as drop-in middleware. Write standard interceptors/middleware for Express (Node.js), net/http (Go), Django/FastAPI (Python), ASP.NET Core (C#), Spring Boot (Java), Laravel (PHP), or Rack (Ruby).
- Discourse Integration: Do not write custom Discourse implementations from scratch. Point users to the official plugin which automatically handles viewing, registration, and login blocks.
- Reverse Proxy IP Extraction (Crucial): If evaluating IPs at the origin server behind a reverse proxy (like Cloudflare), the application MUST extract the IP from the CF-Connecting-IP header, NOT the standard $remote_addr or $req.connection.remoteAddress.