Reaper: The MITM Proxy Built for AI Security Agents
Hook
Most security proxies were built for humans clicking through GUIs. Reaper flips that assumption: it’s an MITM proxy designed to be equally usable by both AI agents and humans, making programmatic security testing a first-class concern.
Context
Traditional application security testing relies heavily on interactive proxies like Burp Suite and OWASP ZAP—powerful tools with rich graphical interfaces where security researchers manually explore attack surfaces, manipulate requests, and analyze responses. But as AI agents become capable of conducting security assessments, these GUI-centric tools create friction. An AI agent doesn’t need colorful syntax highlighting or mouse-driven workflows; it needs structured data, scriptable interfaces, and programmatic access to captured traffic.
Reaper emerges from this shift toward agentic security testing. Built by Ghost Security as part of their broader Skills framework for AI-driven AppSec, it’s a man-in-the-middle HTTPS proxy that prioritizes automation and machine consumption. Rather than presenting a web dashboard or thick client application, Reaper operates as a CLI-first tool that intercepts in-scope traffic, persists everything to a local database, and exposes that data through command-line queries. This architecture appears designed to integrate easily into CI/CD pipelines, feed captured requests into LLM-based security analyzers, or build custom automation scripts that treat HTTP traffic as queryable data rather than ephemeral network streams.
Technical Insight
Reaper’s architecture centers on three core components: an intercepting HTTPS proxy server, a local database for traffic persistence, and a CLI for querying captured data. Written in Go, it likely benefits from the language’s HTTP proxy libraries and concurrent request handling capabilities.
The installation process reflects a minimalist philosophy. A single curl command downloads and installs the binary:
curl -sfL https://raw.githubusercontent.com/ghostsecurity/reaper/main/scripts/install.sh | bashAlternatively, you can download releases directly from GitHub.
The core design revolves around scope management. Rather than capturing all traffic indiscriminately (which would flood your database with requests to CDNs, analytics services, and third-party APIs), Reaper filters based on explicitly defined scope. Only requests matching your target application flow into the database, keeping the signal-to-noise ratio high.
The database-backed approach fundamentally distinguishes Reaper from streaming proxies. Instead of requiring you to inspect traffic in real-time or lose it forever, every in-scope request and response gets persisted. This enables temporal analysis: you can test your application, generate traffic for an hour, then query patterns across that entire session. For AI agents, this is transformative—they can query historical traffic patterns without needing to watch traffic streams live.
The CLI interface exposes this database through search and inspection commands. While the README doesn’t detail specific command syntax (full documentation lives at ghostsecurity.ai), the design pattern is clear: structured queries return structured data. This makes Reaper composable with standard Unix tools and scriptable workflows.
For AI agent integration, Ghost Security positions Reaper within their Skills framework. An AI security agent can programmatically work with Reaper to configure scope, trigger application interactions, then query the captured traffic to identify potential vulnerabilities—searching for authentication endpoints, extracting session tokens, identifying parameter injection points, or detecting sensitive data in responses.
The Go implementation likely compiles to a binary with minimal dependencies, which matters for containerized testing environments and ephemeral CI/CD workers where dependency management can become friction.
Gotcha
Reaper’s platform support stops at Linux and macOS. Windows users are explicitly excluded, which matters if your development team works primarily on Windows or if you need to test Windows-specific application behaviors. While WSL2 might provide a workaround, the officially unsupported status means you’re on your own for troubleshooting.
As an MITM proxy, Reaper requires intercepting and decrypting HTTPS traffic, which typically involves certificate trust modifications. In corporate or restricted environments with strict security policies, you may encounter permissions issues or policy violations. Additionally, applications implementing certificate pinning will reject proxy certificates entirely, preventing traffic interception without application-level configuration changes.
Perhaps most importantly, Reaper is fundamentally a component, not a complete solution. It captures and stores traffic but doesn’t perform vulnerability scanning, fuzzing, or exploitation. You need to build analysis logic on top—either through custom scripts or by integrating with Ghost Security’s AI agent framework. If you’re looking for an all-in-one security testing platform that identifies vulnerabilities out of the box, Reaper will disappoint. Its value emerges when combined with other tools in an automation pipeline, not as a standalone security scanner.
Verdict
Use Reaper if you’re building automated security testing workflows—particularly AI-driven ones—and need a lightweight, scriptable MITM proxy that persists traffic for programmatic analysis. It appears well-suited for CI/CD pipelines, containerized testing environments, and integration scenarios where you’re feeding captured HTTP traffic into custom analysis tools or LLM-based security agents. The database-backed architecture makes it ideal when you need historical traffic analysis rather than just real-time inspection. Skip it if you need Windows support, want a GUI-based interactive testing experience, require built-in vulnerability detection without writing custom analysis code, or work in environments with strict certificate policy restrictions. Also skip it if you’re looking for a complete security testing platform—Burp Suite, OWASP ZAP, or Caido will serve you better as standalone tools. Reaper shines as a building block in larger automation architectures, not as a comprehensive security solution.
