OpenGameAgent: Instructions file for Codex

AGENTS.md

OpenGameAgent AGENTS.md is an instructions file for Codex, OpenCode from EricSun0218/OpenGameAgent. It costs 1,042 tokens per session, scanned A, original, MIT.

Repository instructions for OpenGameAgent, a small C# runtime for game agents that manages structured input, safe actions, game time, actors, and where the engine runs.

In plain words
What is it for?
They are for developing the runtime, persistence, scheduling, memory, skills, sessions, media providers, trace recording, playback, and offline evaluation tools.
Why use it?
They explain the project's boundaries and structure, helping agents preserve its compact core without treating it as a game editor or content marketplace.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is EricSun0218/OpenGameAgent's own configuration. It tells Codex and OpenCode how to work on OpenGameAgent itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything OpenGameAgent configures →

Reuse

Borrowing it

Nothing to install: this file belongs to EricSun0218/OpenGameAgent. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/EricSun0218/OpenGameAgent/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/EricSun0218/OpenGameAgent

Made for: Codex, OpenCode.

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 OpenGameAgent AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/ericsun0218/opengameagent/agents-md.svg)](https://agentmods.dev/instructions/ericsun0218/opengameagent/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/ericsun0218/opengameagent/agents-md"><img src="https://agentmods.dev/badge/instructions/ericsun0218/opengameagent/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,042 This file is loaded in full into every session.
When invoked 1,042 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 5.1 $0.01042 $0.01042
Opus 5 $0.00521 $0.00521
Sonnet 5 $0.00208 $0.00208
Haiku 4.5 $0.00104 $0.00104

Measured 6d ago against content hash ef7430baafa1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

OpenGameAgent 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 6d 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 · 81 lines

How it starts

The opening of the file, as written. The whole thing — 81 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Coding agent guide

Objective

OpenGameAgent is a small C# agent runtime for games. Preserve a compact, understandable core while supporting structured game input, safe actions, game time, multiple actors, and engine/server placement.

This repository is a framework, not a game, world editor, content marketplace, or universal entity schema.

Repository map

  • src/OpenGameAgent.Kernel: engine-neutral stateful model/tool loop.
  • src/OpenGameAgent: game coordinates, runtime composition, actions, sessions, transcript compaction, memory, skills, scheduling, mailboxes, and media contracts.
  • src/OpenGameAgent.Persistence: crash-tolerant local-file implementations.
  • src/OpenGameAgent.DevTools: bounded trace recording, observation-only playback, and offline evaluation.
  • src/OpenGameAgent.Providers.OpenAICompatible: streaming chat-completions transport.
  • src/OpenGameAgent.Providers.MediaHttp: generic remote or local media-generation transport.
  • src/OpenGameAgent.Providers.OpenAI.Images: official OpenAI image generation/edit transport.
  • src/OpenGameAgent.Providers.Volcengine.Images: Volcengine Ark/Seedream image generation/edit transport.
  • src/OpenGameAgent.Media: media model routing plus persistent generated-asset lifecycle contracts.
  • src/OpenGameAgent.Client: engine-compatible JSON/SSE service client.
  • src/OpenGameAgent.Runtime.Protocol: optional versioned, transport-neutral Session/Run/Turn/Item contract.
  • src/OpenGameAgent.Runtime.Hosting: optional in-process Runtime projection and bounded replay journal.
  • src/OpenGameAgent.Models.Credentials.Windows: optional Windows CurrentUser DPAPI credential persistence.
  • src/OpenGameAgent.Server: optional C# .NET 8 host.
  • engines/godot: Godot .NET package and tests.
  • engines/unity: Unity UPM package and tests.
  • engines/unreal: native Unreal Engine C++ plugin for the remote JSON/SSE placement.
  • examples: buildable integration examples.
  • tools/OpenGameAgent.DevTools.Cli: local trace inspection and CI evaluation CLI.
  • tests: focused unit and integration tests.

Read the full file on GitHub · 81 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. 6d ago First seen · 81 lines · 1,042 tokens per session scan A ef7430baafa1

Subscribe to this mod's changes

OpenGameAgent AGENTS.md is an instructions file published in the GitHub repository EricSun0218/OpenGameAgent (46 stars, last pushed 5d ago), licensed MIT. It adds 1,042 tokens to every session, about $0.0052 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 2026-08-30.

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