coding

A set of coding guidelines for building a Rust program that disassembles MOS 6502 machine code into readable instructions, with a terminal interface. It covers the 6502 processor, including undocumented instructions and Commodore 64 memory mapping.

In plain words
What is it for?
Use it when implementing or extending a 6502 disassembler, especially its opcode parser, large-binary viewer, hex dump, register display, or Rust terminal interface.
Why use it?
It helps prevent mistakes when decoding instructions of different lengths and addressing styles, while keeping binary processing safe and the terminal display responsive.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/ricardoquesada/regenerator2000/coding
Any agent
npx skills add ricardoquesada/regenerator2000 --skill coding
Clone the repo
git clone --depth 1 https://github.com/ricardoquesada/regenerator2000

Made for: Claude Code, Codex.

Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 325 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00000 $0.00325
Opus 5 $0.00000 $0.00162
Sonnet 5 $0.00000 $0.00065
Haiku 4.5 $0.00000 $0.00032

Measured 2d ago against content hash 5f5c9d5f2b8b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

coding 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 2d 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.

.agent/skills/coding/SKILL.md · 26 lines

What it actually says

6502 Disassembler Expert Skills

Core Context

  • Project Goal: A 6502 disassembler in Rust with a Ratatui-based TUI, inspired by Borland Turbo Disassembler.
  • Architecture: MOS 6502 (including support for undocumented opcodes and C64-specific memory mapping).
  • Primary Stack: Rust, Ratatui (TUI), and bit-manipulation crates.

Technical Requirements

1. 6502 Logic

  • Always account for variable instruction lengths (1, 2, or 3 bytes).
  • Handle all 13 standard addressing modes (Absolute, Indexed, Indirect, etc.).
  • When requested, include support for "Illegal" opcodes (e.g., NOPs, LAX, SAX).

2. Rust Performance & Safety

  • Use nom or manual bit-shifting for high-performance opcode parsing.
  • Prioritize zero-copy disassembly where possible (using &[u8] slices).
  • Ensure the TUI rendering loop is decoupled from the disassembly engine to prevent UI lag.

3. TUI (Ratatui) Specifics

  • Implement a "Virtual List" approach for the disassembly view to handle large binaries without memory bloat.
  • Mimic the classic Turbo Disassembler layout: Disassembly Window, Register View, and Hex Dump.

Forbidden Patterns

  • Do not use unwrap() on binary parsing; use proper Result handling for corrupted binaries.
  • Avoid heavy standard library abstractions that introduce unnecessary overhead for an embedded-focused tool.
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. 2d ago First seen · 26 lines · 0 tokens per session scan A 5f5c9d5f2b8b

Subscribe to this mod's changes

coding is a skill published in the GitHub repository ricardoquesada/regenerator2000 (164 stars, last pushed 7d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 325 tokens. 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 2026-08-30.