977c9727e6
* fix(environment): keep read-only POSTs out of the write list A POST that repeats the latest read of its path, tunnels only read operations, names a lookup in its path's last meaningful word, or renews a session no longer counts as a state write: it is replayed, does not cut initial windows, and does not end observation searches. A tool stays a write when a related read line changes across one of its calls. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): take an entity an unplanned write made when a read first shows it A successful item read of an entity the gate's copy never held, after a write no built plan models, puts the entity into the copy instead of failing the read, so later writes to it are checked as usual. An entity a modelled write touched is never taken back. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): plan a create into the type its returned id is read under A POST whose path names no state type becomes a create into the type whose item read first names an id its response returned, when the id is new to the state; serving creates in that read's collection. A successful POST that returned an id a type's reads only show after it also ends that type's initial window, so entities a capture created stay out of the initial state. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): end a type's initial reads at the write its reads disagree across When a type's reads disagree across a write under another root, the type's initial window now ends at the earliest write within that change and the state is extracted again, instead of leaving every view of the type replayed. The cut composes with the creation cut; the earlier wins. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): replay request lines that show entities in another form A read line that shows the same entities in another form, by an extra query parameter that adds or drops members, or conflicts with a base line on a shared entity, is a variant: it leaves the view's checks and the entity observations, the view names it with the query keys that pick it out, and a call matching those keys replays its recording. A filter role whose name matches no field needs two agreeing values. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): specify and record the state-target changes Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): keep a read-only POST a write when its evidence is incomplete Body-level container operations are skipped like query ones, a lookup is named only by the path's last literal segment and never alongside a write word, a tool with a redirected or unanswered call is not reclassified, and the mutation veto is resolved over all candidates at once so another read-only call cannot explain a read change. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): answer a field selection only when the state shows it exactly Serving tests a field selection before any variant key: a projection value a replayed read gave, or one no checked line gave other than `*`, replays. A list sets aside a line asking for some fields only before the identity proof, and a dropped variant's membership change no longer rewrites the type. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): hold adopted entities and linked creates to what the recording shows An adopted entity is charged against the view's budget like a created one. A linked create holds only for its exemplar's path arguments: serving refuses others and the gate counts such a call as unmodelled. A response's identity-named id links at any length, but a short one only to a type read before the call. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the review fixes' measurements Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): release a discarded planning pass before planning again A rewrite cut clears the first pass, so the budget rewinds to a checkpoint taken after the write cutoffs and created ids before the state is extracted again. Rewrite spans are charged and appended without spreading them into an argument list. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): link no create whose id an earlier read showed, and read only whole batches A linked create is rejected when an earlier list of its type or read of its collection showed the returned id. Body ids are walked without spreading children into an argument list. An RPC call reads only when every operations entry names an operation of its own. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): let the gate skip exactly the reads serving replays Serving's replay decision moves to the domain as replayReason, and the write gate uses it: a read serving replays can neither approve nor veto a write, and a read of every field beside a replayed selection is checked. A selection read missing a required field is still skipped, since part of an entity can neither confirm nor check it. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the second review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): read writes, links and creation cuts only from evidence that rules out other causes - A read-only POST repeats only a read that finished before it began; the veto compares the latest read finished before a call with the first begun after it, and counts a recorded absence on one side as a change. `modify` and `replace` are write words. - A redirected or unanswered write lets a later item read adopt the entity it may have made. - A creation cut counts a read still running when the POST began as after it, and a list read shows its listed entities' own ids, not those they nest. - A linked create's item read must come before any other tool's write. - Line shapes are charged to the budget as they are built. - A `fields=*` list line is whole, not a field selection. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the third review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): tie linked creates to their returned ids and order state by the lines left - A linked create is observed only in a read of an id its response returned, envelopes included, and serving takes its recorded path values in either spelling. - A list read shows a suffix-named identity (`projectId`) distinct across its entities. - A read-only POST compares the read that finished last before it began. - An entity's first sighting comes from the lines left after variant lines are dropped. - The pairwise variant pass stops at a work limit, leaving every line checked. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the fourth review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): keep foreign keys, stale reads and double decoding out of write evidence - A list read counts a suffix-named field as its entities' ids only when no id-named field identifies them, so an `ownerId` beside `id` cuts no window. - A read-only POST is compared with the read that finished last among those no other write follows, so a consuming call stays a write. - A linked create's source path values compare as spelled on both sides, so no spelling is decoded twice. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the fifth review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): compare linked sources by position, decode path fields once and bound read and variant scans - A linked create's source values compare segment by segment, so a template naming two parameters alike cannot accept a changed first one. - Serving fills a linked create's path fields with its arguments decoded once, as the gate learned them. - The read-only check reads each related line's records once per call, between the nearest other writes. - Member signatures are JSON arrays, so a name holding the separator still conflicts; the variant work limit counts line pairs as well as entities. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the sixth review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): replay late and variant-only items, fill linked path fields from the exemplar and charge membership spans - An item line first recorded after the initial window that names a new shaping parameter and shows other members is a replayed variant, like an initial one. - An item only a replayed line showed, which the state never started with, answers with its own recording; one the state held and lost stays missing. - A linked create fills its path fields from its exemplar's path decoded once, whichever accepted spelling the call sends. - Each membership change span is charged against the budget before it is kept. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the seventh review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): decide late item lines against the lines left, charge replay keys and bisect rewrite cuts - Item lines first recorded after the initial reads are decided once variants are dropped, against the lines left: a new shaping parameter showing other members, or a selection of some fields leaving members out, replays. - Each replay key is charged against the budget before it is kept. - A rewrite span's earliest write is found by bisection over the writes. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the eighth review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): count only reads finished before a linked create began as showing its id held A list still running when the call began may show what the call made, as the creation cut already decides, so it no longer refuses the link. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): keep served creates' items missing, check same-type earlier reads, and bound late lines and read-only stretches - An item only a replayed line showed replays only while no served create has added to its type, so a created and deleted item stays missing. - A linked create's earlier item-read veto checks only reads of the candidate's type or collection that show the item, so another type's id does not hide it. - An item read answered with JSON null shows no id to a creation cut. - Late lines' member names are charged before they are kept. - The read-only check precomputes nearest writes and passes once over each write-free stretch per path, skipping lines whose reads all agree. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the ninth review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(environment): link creates past empty item reads, sweep repeated reads once and keep only returned ids for creation cuts - A linked create passes over a later item read naming its id whose body shows no item, such as JSON null, and links the next one. - Read-only repeated reads are found in one sweep: each path's reads wait by end time until a call's start passes them, and a write clears them. - A creation cut keeps, and charges, only the shown ids some creation returned. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the tenth review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * perf(environment): compare variant lines through shared entities and parse each compared body once The variant pass indexes a tool's lines by the entities they show and compares only lines that share one, charging the index to the budget while it is held; the pairwise work limit still decides when a tool keeps every line checked. Read-only decisions keep each response body's canonical digest, taken once while its parse is charged, across calls and veto passes. The creation cut no longer parses reads at or after the write that ends the initial reads, and reads the ids a body shows inside its lease. Adoption looks up a read's target only after an unplanned write before it. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the eleventh review round's checks Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * perf(environment): list a type's collections only when the path's own holds no id, and parse variant base lines once The write gate's item target lists the type's held collections, and the removed targets', only when the path's own collection holds none of its ids, so a served item view's reads no longer walk every entity of the type. The variant pass parses the base lines' queries once for all the variants they key, and not at all when it found none. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * docs(environment): record the twelfth review round's checks and the sweep's cost Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com> Co-authored-by: Kaoru0822 <208281322+kaoru0822-kitauji@users.noreply.github.com>
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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.
Quick start · How REA works · What you can analyze · Showcases · 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.
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, or IDA 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/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 supports Claude Code, Codex, Cursor, Gemini CLI, Grok Build and other agents. See installation and setup for provider configuration and manual MCP registration.
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.
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.
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 or IDA; 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 |
| ELF notes | PT_NOTE/SHT_NOTE owners, types, GNU build-id and ABI-tag fields | Built-in static ELF inspection; ELF notes |
| 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 and native add-on relationships | 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 |
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.
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
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.
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 Hopper, Ghidra or IDA?
Deep native analysis uses one of them. Static JavaScript and .NET inspection work without a native analysis engine. Setup can install Hopper after approval; Ghidra and IDA use your existing installations. See provider setup.
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
🎉 300,000 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
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.