binary-analysis-patterns

Overview of binary-analysis-patterns skill

What the binary-analysis-patterns skill is for

The binary-analysis-patterns skill is a pattern library for reading compiled code: common x86-64 instruction shapes, calling conventions, stack frame layouts, control-flow structures, and recognizable compiler-generated sequences. It is most useful when you already have disassembly or decompiler output and need to turn low-level instructions into a plausible explanation of program behavior.

Best fit users and jobs-to-be-done

This skill fits security engineers, reverse engineers, malware analysts, CTF players, and developers doing a security audit on native binaries. The real job is not “explain assembly” in the abstract. It is to identify what a function is doing, spot suspicious or vulnerable logic, reconstruct arguments and returns, and move from raw instructions to an audit-ready narrative faster than with a generic prompt.

What makes this skill different from an ordinary prompt

A normal prompt often gives shallow summaries of assembly. The binary-analysis-patterns skill is stronger when you need consistent interpretation of recurring structures such as:

• function prologue and epilogue patterns
• System V AMD64 vs Microsoft x64 calling conventions
• loop, branch, and switch-like control flow
• stack variable usage and frame reconstruction
• compiler idioms that look confusing if read literally

That makes it better for structured binary review than asking a model to “analyze this assembly” with no framework.

What matters before you install

This is a text-first guidance skill, not an automated disassembler, debugger, or signature engine. It does not replace tools like objdump, Ghidra, IDA, radare2, or Binary Ninja; it helps you reason about the output from those tools. If you need automated extraction from binaries, the skill alone is not enough. If you already have snippets, function listings, CFG notes, or decompiler pseudocode, it becomes much more useful.

When binary-analysis-patterns is a strong choice

Use binary-analysis-patterns when you want a reusable interpretation aid for:

• triaging unfamiliar functions quickly
• validating decompiler guesses against assembly
• mapping register usage to function arguments
• recognizing likely library wrappers and boilerplate
• documenting findings for a security audit

How to Use binary-analysis-patterns skill

Install binary-analysis-patterns skill

Install it from the wshobson/agents repository:

npx skills add https://github.com/wshobson/agents --skill binary-analysis-patterns

Because this skill lives at plugins/reverse-engineering/skills/binary-analysis-patterns, install expectations are simple: there are no extra helper scripts or reference packs to configure.

Read this file first

Start with:

• SKILL.md

This skill is concentrated in a single file, so there is little repo archaeology required. Read the headings first to understand its coverage, then use it as a checklist while reviewing your own disassembly.

What input the skill needs to work well

The binary-analysis-patterns skill performs best when you provide concrete binary-analysis artifacts, such as:

• assembly for one function at a time
• decompiler pseudocode plus the matching assembly
• target platform and ABI if known
• symbol names, if partial symbols exist
• your current hypothesis, for example “I think this is argument parsing”
• the security question you care about, such as bounds checks or auth logic

Weak input:

• “Analyze this binary.”

Strong input:

• “Analyze this x86-64 function from a Linux ELF. Assume System V AMD64. Identify the arguments, local variables, likely return value, and whether the control flow suggests input validation or unsafe memory handling.”

Turn a rough goal into a good prompt

A good binary-analysis-patterns usage prompt usually includes five parts:

1. architecture and OS convention
2. function scope
3. output format
4. audit question
5. uncertainty handling

Example:

Use the binary-analysis-patterns skill on the following x86-64 disassembly from a Linux ELF.
Assume System V AMD64 unless the code contradicts it.
For this single function:
1. identify probable parameters and return value
2. describe the stack frame and local variables
3. summarize each branch and loop
4. call out any patterns consistent with parsing, copying, comparison, or allocation
5. note where confidence is low and what extra context would confirm the interpretation

This is better than a generic request because it forces ABI-aware reasoning and a useful output structure.

Suggested workflow for Security Audit

For binary-analysis-patterns for Security Audit, use a narrow, repeatable workflow:

1. export one suspicious function from your RE tool
2. identify platform and likely calling convention
3. ask for frame reconstruction and control-flow summary
4. ask a second pass focused on security-relevant operations
5. compare the result against adjacent caller/callee functions

This works especially well for authentication logic, parsers, deserializers, string handling, and wrapper functions around sensitive APIs.

Use the skill to identify calling conventions early

One of the fastest ways to improve output quality is to tell the model whether the function follows System V AMD64 or Microsoft x64. Many interpretation errors come from wrong assumptions about where arguments live.

Useful prompt addition:

• “This is from Windows x64; treat RCX, RDX, R8, and R9 as early arguments and account for shadow space.”

Without that context, argument mapping and stack interpretation can drift quickly.

Feed assembly in function-sized chunks

Do not paste hundreds of unrelated instructions and expect a clean result. The skill is most reliable on one function or one small control-flow region at a time. If the binary is stripped and messy, start with:

• function entry
• all call sites in that function
• branch targets
• return path

Then expand only after you have a stable hypothesis.

Pair assembly with decompiler output when possible

A practical binary-analysis-patterns guide approach is to provide both low-level and high-level views. Decompiler output is faster to summarize, but assembly reveals where the decompiler may be wrong about:

• signed vs unsigned comparisons
• stack variable boundaries
• indirect calls
• tail calls
• optimized-out frame pointers

Prompt pattern:

• “Use the decompiler output as a hypothesis, but validate it against the assembly before concluding.”

Ask for pattern recognition, not just translation

The skill is more valuable when you ask it to classify code shapes, not merely paraphrase instructions. Good questions include:

• “Is this a counted loop, sentinel loop, or state machine?”
• “Does this prologue suggest a normal frame, leaf function, or optimized omission?”
• “Do these compare-and-branch blocks look like bounds checks or command dispatch?”

That is where binary-analysis-patterns usage starts to outperform ordinary prompting.

Practical output formats that save time

Request one of these formats depending on your task:

• audit notes: issue-oriented bullets with confidence
• reverse-engineering notes: argument list, locals, CFG summary
• decompiler validation: “likely correct / likely wrong / ambiguous”
• triage format: “purpose, evidence, open questions”

For adoption decisions, this matters: the skill is strongest when it feeds a human review workflow, not when used as a black-box final answer generator.

binary-analysis-patterns skill FAQ

Is binary-analysis-patterns good for beginners?

Yes, if you already know very basic assembly concepts and want help recognizing recurring patterns. It is less suitable as a first-ever introduction to reverse engineering because it assumes you can provide relevant disassembly and understand why architecture and ABI details matter.

Does binary-analysis-patterns install any analysis tools?

No. The binary-analysis-patterns install step adds the skill guidance, not a disassembler or debugger. You still need your own tooling to extract assembly, pseudocode, symbols, or CFG context.

When should I use this instead of a normal LLM prompt?

Use binary-analysis-patterns skill when you want more disciplined interpretation of low-level code structure. If your task is “summarize this source file,” a normal prompt is enough. If your task is “reconstruct what this stripped function does and whether it validates input safely,” the skill is the better fit.

Is it limited to x86-64?

The visible emphasis is x86-64, especially calling conventions and function structure. If your target is ARM, MIPS, or WebAssembly, this skill may still help with general reasoning, but it is not the best specialized fit.

Is binary-analysis-patterns useful for malware analysis?

Yes, especially for initial triage of suspicious routines, unpacking helpers, string decoding logic, and API wrapper functions. But it is not a full malware workflow. You still need sandboxing, dynamic analysis, and threat-context tooling outside the skill.

When is binary-analysis-patterns not a good fit?

Skip it if you need:

• automated binary extraction or scanning
• exploit generation
• dynamic instrumentation
• architecture-specific depth outside its covered patterns
• turnkey vulnerability detection without human review

It is a reasoning aid, not a replacement for a reverse-engineering toolchain.

How to Improve binary-analysis-patterns skill

Give stronger context than “analyze this”

The biggest quality jump comes from specifying:

• binary format: ELF, PE, Mach-O
• platform: Linux, Windows, macOS
• architecture: x86-64 if known
• function boundary
• your audit objective

For example:

• “Use binary-analysis-patterns to review this PE x64 function for credential checks and unsafe buffer handling.”

That is much better than a broad request because it narrows both the ABI and the threat model.

Mark uncertainties and known anchors

If you know one call target, one string reference, or one imported API, include it. Even a single anchor can transform the interpretation of surrounding blocks.

Examples:

• “This function calls memcmp shortly before the final branch.”
• “Cross-references suggest this is reached from the login handler.”
• “Decompiler labels one local as a 256-byte stack buffer.”

These anchors reduce hallucinated narratives.

Split analysis into two passes

To improve binary-analysis-patterns results, run it in two passes:

1. structural pass: arguments, stack frame, loops, branches, calls
2. semantic pass: likely purpose, security implications, missing evidence

This avoids mixing uncertain semantics into basic reconstruction too early.

Ask the model to show evidence for each claim

A common failure mode is overconfident interpretation. Reduce that by requiring instruction-level support.

Prompt addition:

• “For every major conclusion, cite the instruction sequence or register behavior that supports it.”

That makes it easier to verify whether the skill is truly reading patterns or merely guessing from superficial cues.

Correct the calling convention explicitly when outputs drift

If the first answer mislabels arguments or locals, do not start over with the same input. Tell it exactly what to fix:

• “Re-run using Microsoft x64, not System V AMD64.”
• “Assume frame-pointer omission and infer locals from rsp offsets.”
• “Treat this indirect call as a possible vtable dispatch.”

Small corrections often recover the analysis quickly.

Focus the improvement loop on audit questions

When iterating, ask narrower follow-ups instead of repeating the entire task. Good examples:

• “Which branch is the actual authentication decision?”
• “Where is length validation performed before the copy?”
• “Are any stack writes indexed by untrusted input?”
• “Does this loop terminate on length or sentinel value?”

This is the fastest way to turn binary-analysis-patterns for Security Audit into actionable review notes.

Compare adjacent functions to refine confidence

If the first output is plausible but thin, provide one caller or one callee. Many binary patterns become clearer when you can see:

• argument preparation at the call site
• cleanup behavior after return
• repeated helper wrappers
• shared error-handling paths

That context often distinguishes business logic from boilerplate.

Use the skill as a hypothesis engine, not final ground truth

The best way to improve binary-analysis-patterns skill results is to treat its output as a structured hypothesis to validate in your RE tool. Check branch conditions, stack offsets, and imported calls before turning conclusions into findings. That workflow is where the skill adds the most value: faster interpretation with less guesswork, while keeping the human analyst in control.