What is state-machine AGENTS.md?

Repository instructions for a deterministic state-machine project. A state machine changes between defined states in response to events, while this project keeps those transitions free of external side effects.

Use them when reviewing, auditing, or changing the state-transition kernel, editor, simulator, or read-only agent tools.

They define the repository's boundaries, rules, data model, and validation requirements for agent work.

How tetracoralla/state-machine configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to tetracoralla/state-machine. 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/tetracoralla/state-machine/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/tetracoralla/state-machine

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/tetracoralla/state-machine/agents-md/github.svg)](https://agentmods.dev/instructions/tetracoralla/state-machine/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/tetracoralla/state-machine/agents-md"><img src="https://agentmods.dev/badge/instructions/tetracoralla/state-machine/agents-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/tetracoralla/state-machine/agents-md"><img src="https://agentmods.dev/badge/instructions/tetracoralla/state-machine/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 468 This file is loaded in full into every session.

When invoked 468 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00468	$0.00468
Opus 5.5	$0.00187	$0.00187
Sonnet 5.5	$0.00094	$0.00094
Haiku 4.5	$0.00047	$0.00047

Measured 1mo ago against content hash 95c0ebedc5f3, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

state-machine 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 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.

AGENTS.md · 48 lines

How it starts

The opening of the file, as written. The whole thing — 48 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Step Switch repository contract

For a requested review, read docs/REVIEW_CONTRACT.md within the requested scope and follow the relevant source and dependencies. It records known risks, not an exhaustive search plan. Report concrete cross-repository implications when found. Review is read-only unless fixes are also requested; this entrypoint does not dispatch another reviewer.

Product boundary

This repository owns a deterministic finite-state transition kernel and two thin surfaces: a technical human editor/simulator and read-only Agent tools. It does not own production workflow orchestration, arbitrary expression evaluation, policy judgment, external side effects, or a complete statechart runtime.

The canonical product model is docs/PRODUCT_MODEL.md. Executable Zod schemas in src/model/schemas.ts own the runtime, CLI, MCP, examples, UI, and published schema contract.

Invariants

step is a pure function of machine, snapshot, event, and explicit guard outcomes. The kernel never executes user code or external effects.
Effects are symbolic intents. Simulation returns them; a host decides whether a separately authorized executor may act on them.
Guards are named symbols. The caller supplies their boolean outcomes; the kernel does not recreate the Decision Table or expression interpreter.
Context assignment uses the tagged literal, event, and context value sources only. Reject unknown fields and unsafe prototype-path segments.
One state/event pair owns at most one transition in v0.1. An absent transition is an ordinary deterministic rejection, not an inferred action.
Final states cannot have outgoing transitions. Every target, event, and guard reference must exist.
MCP tools accept inline data only and are read-only, idempotent, bounded, and closed-world. Do not add ambient filesystem access.
Apply request-wide state, transition, event-sequence, depth, byte, and response limits cumulatively.

Validation lanes

Run npm run check for development regression. Separately exercise the built CLI, MCP stdio transport, and browser editor/simulator before claiming those runtime surfaces work. Business/experience acceptance remains the owner's judgment after opening the current interface.

Read the full file on GitHub · 48 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.

1mo ago Changed · +1 lines · +5 tokens per session 95c0ebedc5f3
2mo ago First seen · 47 lines · 463 tokens per session scan A 00362d8f588d

Subscribe to this mod's changes

state-machine AGENTS.md is an instructions file published in the GitHub repository tetracoralla/state-machine (0 stars, last pushed 29d ago), licensed Apache-2.0. It adds 468 tokens to every session, about $0.0019 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.

state-machine AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
state-machine AGENTS.mdtetracoralla/state-machine	Instructions file	0	29d ago	Apache-2.0	A	468	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	today	MIT	A	7,461	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	5,685	GitHub Copilot
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	3,093	GitHub Copilot
vscode model-prompts.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	2,022	GitHub Copilot

state-machine: Instructions file for Codex