arcadeactions AGENTS.md

Project-specific coding instructions for Arcadeactions, a library that controls motion and behavior in Arcade projects. They define the reading order, code structure, dependency design, and testing expectations.

In plain words
What is it for?
Use them when implementing or reviewing Arcadeactions code. They cover reading project documentation, designing sprite and window interfaces, using injected dependencies, and running Python commands and tests correctly.
Why use it?
They give coding agents the project context and rules needed to make changes that fit the existing codebase. They also reduce problems caused by hidden dependencies, oversized modules, and unchecked object access.

Instructions file for CodexOpenCode

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 instructions/bcorfman/arcadeactions/agents-md
Clone the repo
git clone --depth 1 https://github.com/bcorfman/arcadeactions

Made for: Codex, OpenCode.

Per session 242 This file is loaded in full into every session.
When invoked 242 The same file — it is already loaded in full.
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 $0.00242 $0.00242
Opus 5 $0.00121 $0.00121
Sonnet 5 $0.00048 $0.00048
Haiku 4.5 $0.00024 $0.00024

Measured 2d ago against content hash 6fd2b4bd7017, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

arcadeactions AGENTS.md 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.

AGENTS.md · 23 lines

What it actually says

Read before coding:

  • Follow docs in order: docs/prd.md -> docs/api_usage_guide.md -> docs/testing_guide.md.
  • Refer to /docs for any context or patterns before implementation.

Design priorities (in order): dev experience, simplicity, fit with underlying APIs, API quality, testability, best practices.

Structure/complexity:

  • Keep modules around ~500 lines and functions around ~20 cyclomatic complexity.
  • Split modules/functions intelligently to avoid high complexity or large files.
  • If splitting would reduce clarity, ask for a decision before doing it.

Hard rules:

  • Avoid dataclasses unless there is a clear, documented benefit.
  • Avoid runtime type/attribute checks (hasattr/getattr/isinstance/EAFP-with-pass).
  • No silent EAFP; except AttributeError: pass is forbidden.
  • Use uv run python (never plain python).
  • Define and use explicit Protocols/adapters for sprite/window/action interfaces; validate at boundaries instead of ad-hoc attribute probes.

Dependency/testability:

  • Accept dependencies via constructors; avoid hidden instantiation inside methods.
  • Avoid circular dependencies.
  • Prefer composition over inheritance for dependencies.
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 · 23 lines · 242 tokens per session scan A 6fd2b4bd7017

Subscribe to this mod's changes

arcadeactions AGENTS.md is an instructions file published in the GitHub repository bcorfman/arcadeactions (5 stars, last pushed 8d ago), licensed MIT. It adds 242 tokens to every session, about $0.0012 per session on Opus 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.