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REA: Reverse Engineer Anything

One MCP for reverse engineering across binaries, applications, and runtime behavior.

See a feature you like. Understand how it works, down to the binary level.

Website · Guides · Showcases

Quick start · How REA works · What you can analyze · Showcases · Build RL environments · FAQ · Documentation

npx rea-agents setup

Important

Get REA from morluto/rea, rea.tools, or the rea-agents npm package. Follow the installation and release links from these official sources. A similar repository name or copied README does not establish that a download is official.

Join the Reverse Engineering Community Discord · Q&A · Show and Tell

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See a feature in an app that you want in your own product? Ask your agent to investigate it with REA. It can inspect the app without its source code, explain how the feature works, show the evidence, and build a version for your project.

REA connects your agent to tools for inspecting native binaries, JavaScript and Electron apps, .NET assemblies, and websites. You can also use the same tools from your terminal. Analysis runs locally, and results include the evidence and limitations behind each conclusion.

Setup registers REA with your agent and installs matching workflow instructions. Native analysis can use an existing Hopper, Ghidra, IDA or Kuna installation; setup can optionally install Hopper with approval. Static JavaScript analysis needs no native analysis engine.

Visit the REA website for setup instructions, illustrated guides, and real case studies.

Quick start

On Linux, Ghidra, JADX, firmware tool launches and static JavaScript/Electron analysis require a procps-compatible ps on REA's PATH for process ownership checks. Recovery steps are in docs/getting-started/installation.md under "Linux owned-process prerequisite".

Set up your agent

With Node.js and npm installed, run:

npx rea-agents setup

Choose your agents, review the proposed changes, and approve them. Setup adds REA's MCP server and matching workflow instructions, with backups of existing configuration. Restart your agent afterward. Setup records the selected runtime and REA entry script directly. If acquired through a package runner, keep its cache entry available. Run package acquisition from a trusted directory outside the target project. Installation and recovery details are in the setup guide below.

Setup supports Claude Code, Codex, Cursor, Gemini CLI, Grok Build and other agents. See installation and setup for provider configuration, manual MCP registration, Claude Code/Codex plugins, and the Cursor Marketplace plugin.

MCP uses compact input schemas by default to reduce context overhead. Set REA_MCP_INPUT_SCHEMA_PROFILE=full in your MCP registration when you need the complete advertised field guidance and nested validation details. Both profiles keep the full tool set and canonical server validation. See "Compact input schema profile" in the MCP contracts guide.

Complete output schemas are advertised by default. If your client caps the complete tools/list frame, set REA_MCP_OUTPUT_SCHEMA_PROFILE=compact to bound each advertised output schema, or off to omit output schemas entirely. Both settings keep canonical server-side validation and complete structured results. See "Output schemas" in the MCP contracts guide.

Ask your agent

Understand how search works in the Notes app, show me the evidence, and build a
similar feature for my project.

Replace Notes with your target app and the feature you want to understand.

Use the terminal

Inspect an extracted JavaScript/Electron app directory or ASAR:

npx -y rea-agents@latest analyze-javascript-application /absolute/path/to/app --json

The result includes modules, imports, Electron boundaries and their evidence. Replace the path with your target, such as "D:/apps/example" on Windows.

To install the rea command for regular use:

npm install --global rea-agents
rea --help

For native analysis, configure a provider first. See the CLI and Evidence guide for native commands, provider selection, snapshots and scripting.

Update REA

REA changes quickly, and new releases include frequent bug fixes. Keep your installation up to date.

For a CLI installed with npm install --global or bun add --global:

rea update

rea --update is an alias for this verified workflow and accepts the same global output flags. Use rea update when combining it with other command controls.

Updater commands retain at most 4 MiB of stdout and stderr combined. Oversized metadata replies are rejected after the command exits; verbose installs continue with bounded diagnostics. Human progress output respects terminal backpressure and waits for submitted writes to finish.

Bun global updates require Bun 1.2.17 or later. With an older Bun release, upgrade Bun manually before running rea update.

To refresh your agent registrations and skill, run the setup command printed by the update.

If you use npx, update your agent setup with:

npx rea-agents@latest setup

Review the setup changes and restart your agent. For one-off CLI commands, use npx rea-agents@latest followed by the command. With Bun, use bunx rea-agents@latest in place of npx rea-agents@latest.

How REA works

Your agent calls REA through MCP to inspect the target and trace relevant code. REA returns findings with their evidence. The agent uses them to ask follow-up questions, explain the behavior, or write and test an implementation. CLI commands use the same workflows.

Open the full-size figure.

What you can analyze

REA requires Node.js 22.x (>=22.23.4), 24.x (>=24.22.1), or 26.12.1+, plus npm. Additional tools and host support depend on the target:

Target	What REA returns	Requirements and guide
Desktop installations	Runtime candidates, supporting files, component markers and next probes	Built-in bounded directory/header inspection; desktop applications
Native binaries	Pseudocode, assembly, strings, symbols, calls and references	Hopper, Ghidra, IDA or Kuna; native analysis
Offline ELF layout	Sections, segments, original symbols/relocations and static mitigation candidates	Caller-supplied pwntools on Linux x64; binary diagnostics
Go binaries	Embedded compiler version, modules, replacements and build settings	Built-in static ELF/PE/thin Mach-O inspection; no Go installation required
GPU code objects	CUDA/HIP targets, selected kernel parameters and resources, retained PTX text	Built-in static ELF/PE/fatbin/CUBIN/PTX inspection; GPU code objects
Model artifacts	GGUF / safetensors metadata, tensor declarations and derived totals	Built-in header inspection; optional full-file hash; model files
IL2CPP metadata	Unity global-metadata.dat assembly images, type and method names and index ranges	Built-in static decoding of versions 24, 27, 29, 31 and 39; no Unity required
Godot PCK	Archive inventory and extraction, original header/directory facts and selected content identities	Built-in static formats 2, 3 and 4; no Godot required
Rust binaries	Embedded cargo-auditable crate names, versions, sources and dependency edges	Built-in static ELF/PE/thin Mach-O inspection; Rust binaries
PE certificates	Authenticode WIN_CERTIFICATE entries and PKCS#7 signer/X.509 identity fields	Built-in static PE inspection; PE certificates
PE imports	Import and delay-load DLL names, ordinals, IAT RVAs and pefile import hash	Built-in static PE inspection; PE imports
Windows shortcuts	Shell Link target, arguments, working dir, ExtraData and Tracker droid facts	Built-in static LNK inspection; Windows shortcuts
ELF notes	PT_NOTE/SHT_NOTE owners, types, GNU build-id and ABI-tag fields	Built-in static ELF inspection; ELF notes
Binary hardening	PIE, NX, RELRO, CFG and related header flags for ELF, PE and Mach-O	Built-in static header inspection; binary hardening
Apple IPS crashes	.ips metadata, threads, images, registers and documented crash classes	Built-in static JSON inspection; Apple IPS
Linux kernel modules	.modinfo keys, __versions CRCs, this_module presence, and signature trailer	Built-in static ELF inspection; kernel modules
Erlang BEAM	IFF chunks, atoms, exports, imports, lambdas and the Code header	Built-in static BEAM inspection; Erlang BEAM
WASM artifact	Validation, sections, exact import/export WAT forms and decoded WAT	Caller-supplied WABT 1.0.42; inspect_wasm_artifact
EVM bytecode	Dispatch selectors, byte offsets, inferred arguments and mutability	Local raw/hex carrier on Linux x64; offline EVM guide
SQLite databases	Tables, columns, indexes, views, triggers and selected ordinary-table rows	Local database/WAL snapshot; Node.js 24.x >=24.15 or 26+ with native SQLite limits
Recorded Linux crashes	Raw notes, every recorded thread's registers/signals and optional mapping candidates	Caller-supplied pwntools on Linux x64; optional GDB/pwndbg; recorded crashes
JavaScript / Electron	Modules, imports, source maps, routes, IPC, native add-ons, rea audit-release-exposure	Node.js and npm; Linux: procps-compatible ps; application analysis
Websites	Page structure, scripts, network observations and requested screenshots	A Chrome-family browser; browser analysis
Saved network captures	Requests, responses, exposed payloads and source locations	HAR or Fiddler Everywhere SAZ; mitmdump on Linux for native mitmproxy; capture guide
.NET assemblies	Metadata, CIL instructions, declared native dependencies and build comparisons	None (static only); managed-code guide
Android APKs	Manifest declarations, classes, decompiled methods and references	Headless JADX and a full JDK on Linux/macOS/Windows x64; Android guide
APK signatures	v1/v2/v3/v3.1 signers, certificate fingerprints, key rotation and digest self-consistency	None (static only); inspect_apk_signature
Android devices	Devices, packages, processes, logs, dumps, screen captures, and APK/file transfers	Caller-supplied adb (emulator or hardware); ADB guide
JEB projects	Engine-backed project units, artifact digests and type/method pseudo-code	A caller-started JEB client serving MCP, selected with REA_JEB_MCP_URL; JEB guide
Android resources	Decoded manifest, string tables, locales and version facts	Caller-supplied Apktool launcher; resource guide
Flutter apps	Dart snapshot hash, per-ABI library digests and engine build provenance	None (static APK parsing); Flutter guide
Firmware	Regions, extraction results and native-analysis handoffs	Binwalk / Unblob on Linux; firmware guide
Recorded packets	Selected fields, repeated values, filters and decode-as rules	Linux: TShark 4.x + prlimit; capture guide
Packet summaries	Endpoints, DNS, TLS SNI, protocol distribution and HTTP requests	Caller-supplied tshark and capinfos (Linux-verified); pcap guide
Recorded logic signals	Decoder annotations, sample ranges and diagnostics	Linux: sigrok-cli 0.7.2 + prlimit; signal recordings
Packages and resources	File inventories, digests, plists, Apple bundle anatomy and extracted resources	Artifact and JavaScript guide, Apple applications
Process behavior	Terminal output, interactions, exit and filesystem observations, and run comparisons	Linux/macOS with a native PTY; process capture
PyInstaller executables	CArchive members, Python version, entry scripts and extracted bytecode	None (static only); Python packaged applications
Deno compile binaries	Virtual files, entry point, recorded options, npm snapshot length	None (static only); Deno compile executables

Static JavaScript and .NET inspection read the supplied files without running the application. Runtime capture runs or interacts with the selected target using your user permissions; each runtime guide describes its effects.

For offline native-binary inspection, REA also supports caller-supplied GNU objdump and Rizin. See the reverse-engineering tools guide for provider setup, CLI commands, and Evidence limitations. REA does not install or update either provider.

Native formats and host support vary by provider. See Hopper and Ghidra setup, the IDA guide (including an optional native MCP bridge), the Kuna decompiler guide, and experimental Windows Ghidra support. Ghidra also supports 16-bit DOS analysis. For large binaries, raise the provider's startup deadline with REA_GHIDRA_STARTUP_TIMEOUT_MS or REA_HOPPER_STARTUP_TIMEOUT_MS. For provider selection, see the CLI guide. Check release availability for features added since the latest npm release.

Showcases

DX-Ball: reconstruct a sound-pan calculation

Follow a sound call into its position-to-pan helper, inspect the instructions, and turn incomplete pseudocode into C. The reconstruction passes 3,205 original-x86 cases and reproduces all 63 compiled function bytes.

Read the case study · Reconstruction repository

Notion: trace the Electron clipboard bridge

Find the renderer's clipboard API, follow it through preload and IPC into the main process, and inspect the rich clipboard format.

Read the case study

TH04: recover a DOS bullet-ring calculation

Inspect the original PC-98 game's 16-bit instructions, recover the fixed and aimed angle calculations, and compare the reconstructed C++ with the historical compiler output.

Read the case study · Reconstruction repository

Build RL environments with REA

Record a web app session, turn its API into tools, and export an environment an AI agent can use. Run it with AgentEnv, then add tasks and reward checks for RL training or evaluation.

Read the guide · Watch the video

If you've used REA on something interesting, we'd love to see it. Share your case in an issue or a pull request, including the target, your question, how REA helped, and what you found.

Build RL environments

Give an AI agent a local environment to practice tasks such as finding an issue or creating a folder, without running the original app. Use it for reinforcement learning (RL) or to test how well an agent completes tasks.

REA turns recorded API requests and responses into tools the agent can call. The environment uses the recorded data and supports changes only when the recording confirms their effects.

With REA set up in your agent, replace the example URL and folder tasks below with your own:

Use REA to build an RL environment from my test web app at
http://127.0.0.1:3000.
Cover listing, creating, renaming, and deleting folders. You may create and
remove test folders. Leave existing data unchanged.
Save it in a folder named my-env. Check which operations work and tell me
how to run it.

Use the command line instead

Use these commands if you already have a file containing the app’s recorded browser requests and responses. Running the result also requires AgentEnv and Docker.

rea environment-build ./session.har ./my-env --name my-env --json
agent-env run ./my-env

REA exports a runnable environment with a basic test to check that it starts and responds. Use it with your RL framework to define task goals, add reward checks, and run training.

Build an environment · Environment reference · Watch the demo on X

Desktop app environments

REA can also build an environment of a Linux desktop app, which an agent uses through screenshots, the mouse and the keyboard. From a one-line request, such as "Build me a Gnote environment where the agent adds olive oil to the shopping list note", your agent installs the app on a local build computer, writes the task, exports the environment and checks the task in a fresh computer. The machine that builds it needs Linux on amd64 or arm64, Docker and the agentenv framework version the guide pins.

Set up desktop app environments

FAQ

Which agents can use REA?

Any agent that supports local MCP servers. Setup configures the supported agents; other clients can use manual MCP registration.

Do I need a native analysis engine?

Deep native analysis uses Hopper, Ghidra, IDA or Kuna, depending on the target and operation. Static JavaScript and .NET inspection work without a native analysis engine. Setup can install Hopper after approval; Ghidra, IDA and Kuna use your existing installations. See provider setup for the options and their supported targets.

Do I need to start Hopper first?

REA starts Hopper when an operation needs it. On macOS, a first-run dialog may ask you to choose demo mode or activate your license. Complete that prompt in the same user session before your first CLI/MCP operation or unattended job. Open Hopper manually if needed. See Hopper startup and troubleshooting.

What does installing the skill from skills.sh do?

The skill supplies investigation instructions for your agent. Use npx rea-agents setup to register REA's MCP server and install the matching instructions, then restart your agent. See skill-only installation.

What code does REA return?

Native analysis returns pseudocode and assembly. JavaScript/Electron analysis recovers modules and their relationships. Your agent uses these findings to write and test an implementation; the showcases give worked examples.

Does REA upload my app?

REA analyzes targets locally. Your agent receives the tool results, and its model provider has its own data policy.

What should I do if I hit a bug?

Update first; a recent release may already fix it.

For a CLI installed with npm install --global or bun add --global:

rea update

For agent setup through npx:

npx rea-agents@latest setup

If you're using an agent, complete the setup refresh and restart it. Retry the same task. If the problem persists, open an issue with your REA version, target type, steps to reproduce and error output.

Documentation

Start with the website's worked guides. For exact options, prerequisites and result contracts:

• Installation and setup: agent registration, provider configuration, updates and uninstall.
• Readiness and troubleshooting: diagnose one agent or analysis engine.
• CLI and Evidence: commands, provider selection, snapshots, import/export and exit statuses.
• MCP contracts and agent prompts: tool results, sessions and guided investigations.
• Tool catalog: generated inventory of tools, providers and CLI commands.
• Roadmap: planned work and capability trackers.

Report vulnerabilities through SECURITY.md.

Star history

🎉 400,000 GitHub stars — thank you!

Thanks to everyone using REA, reporting bugs, requesting features, testing builds, and contributing fixes.

Disclaimer

See DISCLAIMER.md for responsible-use guidance.

The project's position on illegal or unauthorized use covers all REA versions, distribution channels, and platforms; each copy retains its applicable licenses.

REA is for lawful research, education, interoperability, software preservation, and analysis of software you own or are authorized to examine.

Contributing

We'd love your help with REA! Open an issue to report a bug or suggest a feature, or send a pull request to improve the code or docs.

See CONTRIBUTING.md for development setup and checks, testing for verification lanes, and the architecture map for selected layers and dependency paths.

License

MIT

REA-authored code is licensed under MIT. Third-party material retains its own licenses and copyright notices; see Third-party notices for the dependency inventory, preserved license texts, and external-tool terms.

You must legally obtain and be authorized to use commercial tools, including IDA Pro / Hex-Rays decompilers, Hopper, and JEB, under their applicable licenses. REA grants no tool license, key, or activation entitlement. Trials and demos remain subject to vendor terms, including user, feature, automation, and output sharing restrictions. Cracked copies, stolen keys, unauthorized key sharing, and bypassing license restrictions are not authorized. This guidance does not amend MIT or third-party licenses.