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AI API reverse engineering: private APIs and protocols decoded with AI

API and protocol reverse engineering is about working out how two pieces of software talk when there is no public documentation. The projects on this page used a language model to decode undocumented interfaces: the messages a lamp or home battery sends over Bluetooth, the binary frames a web app sends over a WebSocket, and private system frameworks on macOS and Windows. A common approach is to give the model a decompiled companion app, or a capture of real traffic, and ask it to describe the message format and write a small client. The model is quick at spotting structure in hex dumps and following code paths in decompiled Java or JavaScript. The person tests each command against the real device or service and corrects the model when it guesses. Most authors did this for interoperability, such as adding a device to Home Assistant. Each entry links the source and lists the model, tools and outcome.

Projects
7
Outcomes
Works6Partial1
Models used
Claude7
7 projects

The projects

Works
Blog · APIs and protocols
Pick

Controlled Amaran studio lights over Bluetooth mesh without the vendor app

$91.34 and 3.5 hours of /goal later, the lights work without the app.

Time About 3.5 hoursCost $91.34
Works
Blog · APIs and protocols

Reverse engineered Apple Neural Engine private APIs with Claude to train networks on the M4 ANE

Training neural networks on Apple's Neural Engine without CoreML.

Model Claude Opus 4.6
Works
Blog · APIs and protocols

Reverse engineered a home battery's Bluetooth and cloud protocols in one day

A home battery's Bluetooth and cloud protocols, documented in one day.

Time About 8 hours, in one day
Works
Blog · APIs and protocols

Bluetti inverter cloud API and BLE protocol, bridged to Home Assistant

A home battery's cloud and Bluetooth protocols, into Home Assistant in an evening.

Time One evening for the cloud gateway, a weekend for BLE
Works
GitHub · APIs and protocols

Decoded Figma's binary WebSocket protocol into a library, CLI and MCP server

Figma designs, read straight off the wire, with no rate-limited API.

Model Claude
Works
Blog · Websites

Extracted an encrypted WebSocket site's API in about half an hour

An encrypted WebSocket site turned into a working API client in about 30 minutes.

Time About 30 minutes
Partial
Blog · APIs and protocols

Clean-room Direct2D replacement for Paint.NET on WINE

About 180,000 lines of clean-room Direct2D, so Paint.NET runs under WINE.

Time About 3 weeks
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FAQ

Common questions

The model reads a decompiled client app or a traffic capture, describes the message format, and writes a client that can be tested against the real service. The person runs those tests and feeds back what failed.

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