assembly

assembly is a skill for Claude Code, Codex from G1Joshi/Agent-Skills. It costs 41 tokens per session (1,330 once invoked), scanned A, original, MIT.

A low-level programming language that maps closely to a computer processor’s instructions. It is used when software must directly control hardware or memory.

In plain words
What is it for?
Use it for operating-system kernels, embedded devices, reverse engineering, or rare cases requiring extreme optimisation.
Why use it?
It gives precise control over how a processor runs code, which higher-level languages may hide. The trade-off is that it is difficult to read and write.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it for operating-system kernels, embedded devices, reverse engineering, or rare cases requiring extreme optimisation.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/g1joshi/agent-skills/assembly
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add G1Joshi/Agent-Skills --skill assembly
Clone the repo
git clone --depth 1 https://github.com/G1Joshi/Agent-Skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for assembly

README.md
[![agentmods](https://agentmods.dev/badge/skills/g1joshi/agent-skills/assembly/github.svg)](https://agentmods.dev/skills/g1joshi/agent-skills/assembly)
Your own site
<a href="https://agentmods.dev/skills/g1joshi/agent-skills/assembly"><img src="https://agentmods.dev/badge/skills/g1joshi/agent-skills/assembly/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for assembly

Your own site · 80×15
<a href="https://agentmods.dev/skills/g1joshi/agent-skills/assembly"><img src="https://agentmods.dev/badge/skills/g1joshi/agent-skills/assembly.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 41 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,330 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00041 $0.01330
Opus 5.5 $0.00016 $0.00532
Sonnet 5.5 $0.00008 $0.00266
Haiku 4.5 $0.00004 $0.00133

Measured 22d ago against content hash 5b781ac3df57, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

assembly scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 22d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/languages/assembly/SKILL.md · 142 lines

How it starts

The opening of the file, as written. The whole thing — 142 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Assembly

Low-level language with a very strong correspondence between the instruction in the language and the architecture's machine code instructions.

When to Use

  • Low-Level Hardware & OS Kernel Programming: Writing bootloaders, CPU context switches, interrupt handlers, and page table setup.
  • Micro-Architectural SIMD Vector Optimization: Crafting hand-tuned AVX-512, Neon, or SSE assembly kernels for game physics and matrix multiplication.
  • Reverse Engineering & Exploit Analysis: Disassembling binary executables to audit firmware, analyze malware, or debug compiler crashes.
  • Embedded Bare-Metal Firmware: Direct CPU register manipulation on microcontrollers without operating system abstractions.

Quick Start

section .data
    msg db "Hello, World!", 0xa
    len equ $ - msg

section .text
    global _start

_start:
    mov rax, 1      ; write syscall
    mov rdi, 1      ; stdout
    mov rsi, msg    ; buffer
    mov rdx, len    ; length
    syscall

    mov rax, 60     ; exit syscall
    xor rdi, rdi    ; exit code 0
    syscall

Core Concepts

CPU Registers & Memory Addressing Modes (x86-64 / ARM64)

Registers hold immediate state for execution; addressing modes compute memory operands:

; x86-64 NASM: Moving data and base-index-scale-displacement addressing
mov rax, 42                     ; Immediate to register
mov rbx, [rsp + 16]             ; Base + displacement
mov rcx, [rdi + rsi * 8 + 32]   ; Base + index * scale + displacement

The System V AMD64 Calling Convention

Governs how functions receive parameters and return values in Linux and macOS:

Register Argument Role
rdi 1st function argument
rsi 2nd function argument
rdx 3rd function argument
rcx 4th function argument
r8, r9 5th and 6th function arguments
rax Function return value (and syscall number)

Read the full file on GitHub · 142 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 22d ago Changed 5b781ac3df57
  2. 26d ago Changed · +73 lines · +23 tokens per session fe2095e4de6b
  3. 1mo ago First seen · 69 lines · 18 tokens per session scan A fa92e15adc2e

Subscribe to this mod's changes

assembly is a skill published in the GitHub repository G1Joshi/Agent-Skills (15 stars, last pushed 22d ago), licensed MIT. It adds 41 tokens to every session and 1,330 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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