cartridge-programming

cartridge-programming is a skill for Claude Code, Codex from nschneir/Project64. It costs 96 tokens per session (4,445 once invoked), scanned A, original, no licence file.

A guide to creating and debugging software cartridges for the Commodore 64, a 1980s home computer. It covers standard 8K or 16K cartridges, Ultimax mode, and bank-switched EasyFlash cartridges.

In plain words
What is it for?
It is for building cartridge-based Commodore 64 programs with the c64 command-line tools or c64-tools server.
Why use it?
Cartridges must start through specific hardware paths and place code in the correct memory areas. This guide helps avoid boot and memory-mapping errors.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit It is for building cartridge-based Commodore 64 programs with the c64 command-line tools or c64-tools server.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/nschneir/project64/cartridge-programming
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 nschneir/Project64 --skill cartridge-programming
Clone the repo
git clone --depth 1 https://github.com/nschneir/Project64

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 cartridge-programming

README.md
[![agentmods](https://agentmods.dev/badge/skills/nschneir/project64/cartridge-programming/github.svg)](https://agentmods.dev/skills/nschneir/project64/cartridge-programming)
Your own site
<a href="https://agentmods.dev/skills/nschneir/project64/cartridge-programming"><img src="https://agentmods.dev/badge/skills/nschneir/project64/cartridge-programming/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 cartridge-programming

Your own site · 80×15
<a href="https://agentmods.dev/skills/nschneir/project64/cartridge-programming"><img src="https://agentmods.dev/badge/skills/nschneir/project64/cartridge-programming.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 96 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,445 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 unknown 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 $0.00096 $0.04445
Opus 5.5 $0.00038 $0.01778
Sonnet 5.5 $0.00019 $0.00889
Haiku 4.5 $0.00010 $0.00445

Measured 1mo ago against content hash d786731c078f, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

cartridge-programming 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 1mo 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/cartridge-programming/SKILL.md · 331 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 1mo ago First seen · 331 lines · 96 tokens per session scan A d786731c078f

Subscribe to this mod's changes

cartridge-programming is a skill published in the GitHub repository nschneir/Project64 (3 stars, last pushed 2mo ago), with no licence file. It adds 96 tokens to every session and 4,445 once invoked, about $0.0004 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 2026-08-31.

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