summer-engine-agent AGENTS.md

summer-engine-agent AGENTS.md is an instructions file for Codex, OpenCode from SummerEngine/summer-engine-agent. It costs 1,263 tokens per session, scanned A, original, MIT.

Project instructions for an AI coding agent working on Summer Engine, an AI-focused game engine whose projects commonly use GDScript. They describe the engine's files, tools, rules, and development workflow.

In plain words
What is it for?
Useful for diagnosing and editing Summer games, navigating the project structure, using the engine's connected tools, and following the appropriate skills and tests.
Why use it?
They help the agent understand the game project before changing it and reduce mistakes when working with scenes, assets, runtime behavior, or persistent data.

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/summerengine/summer-engine-agent/agents-md
Clone the repo
git clone --depth 1 https://github.com/SummerEngine/summer-engine-agent

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 summer-engine-agent AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/summerengine/summer-engine-agent/agents-md.svg)](https://agentmods.dev/instructions/summerengine/summer-engine-agent/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/summerengine/summer-engine-agent/agents-md"><img src="https://agentmods.dev/badge/instructions/summerengine/summer-engine-agent/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,263 This file is loaded in full into every session.
When invoked 1,263 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 $0.01263 $0.01263
Opus 5 $0.00632 $0.00632
Sonnet 5 $0.00253 $0.00253
Haiku 4.5 $0.00126 $0.00126

Measured 6d ago against content hash d6c6b2105272, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

summer-engine-agent 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 · 59 lines

How it starts

The opening of the file, as written. The whole thing — 59 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Summer — Agent Context

This file is for any AI agent that loads context from AGENTS.md (Codex CLI, Factory Droid, etc). It mirrors the Summer onboarding rules — see GEMINI.md for the same content keyed for Gemini.

What you're working with

Summer Engine is the AI-native game engine the user is building in. The user is making a Summer game with the Summer SDK, normally in GDScript. The editor, scene graph, asset pipeline, and runtime are instrumented for programmatic control through the summer-engine MCP server. Summer currently uses the 4.6.1 upstream technical base, plans to adopt 4.7.1 next, and follows upstream continuously. Those numbers are compatibility facts, not the product identity. Projects use GDScript (.gd), C# (.cs), scenes (.tscn/.scn), resources (.tres/.res), and the technical project.godot filename.

Critical rules

  1. Always check for a relevant Summer skill before responding. Even a 1% chance a skill applies = invoke it. Start with summer:using-summer on every fresh Summer Engine session.
  2. The user owns fix decisions. Diagnose first, propose, ask, then edit.
  3. Don't grep the whole project before reading the actual error. Use summer_get_script_errors first.
  4. Don't edit .tscn files directly while the engine is running. Use the summer_* MCP tools — direct edits get overwritten when the editor saves.
  5. Never call summer_set_resource_property against an inline sub_resource — it silently drops the value. Instantiate via summer_set_prop with a class-name string first.
  6. Every scene mutation names its target. Pass the exact res://...tscn as scenePath to add/set/remove/replace/connect/instantiate/save tools and mutation batches. summer_open_scene is a user-visible tab action, not a prerequisite or target selector.
  7. Never mix OpenScene with scene mutations in one batch. Send the UI action separately; scenePath already selects the mutation target.
  8. Save once at the transaction boundary. Dedicated scene mutation tools and summer_batch append one final SaveScene. Raw engine batches must include one final SaveScene themselves.

Read the full file on GitHub · 59 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 · 59 lines · 1,263 tokens per session scan A d6c6b2105272

Subscribe to this mod's changes

summer-engine-agent AGENTS.md is an instructions file published in the GitHub repository SummerEngine/summer-engine-agent (57 stars, last pushed yesterday), licensed MIT. It adds 1,263 tokens to every session, about $0.0063 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.