ha-mcp: Instructions file for Codex

AGENTS.md

ha-mcp AGENTS.md is an instructions file for Codex, OpenCode from homeassistant-ai/ha-mcp. It costs 2,867 tokens per session, scanned A, original, MIT.

Repository instructions for a project that uses Git worktrees, which are separate working folders linked to different branches. They explain that AGENTS.md is the main guide, CLAUDE.md points to it, and feature work belongs in the worktree directory.

In plain words
What is it for?
Creating and using worktrees, locating repository guidance, organizing scratch files, and developing new skills in the expected directories.
Why use it?
They prevent agents from editing the wrong branch or folder and describe the expected layout before making changes.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions AGENTS.md.

This is homeassistant-ai/ha-mcp's own configuration. It tells Codex and OpenCode how to work on ha-mcp 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 ha-mcp configures →

About the project

ha-mcp is an unofficial Model Context Protocol server that lets AI assistants interact with Home Assistant, including controlling devices, checking states, running services, and managing automations. Home Assistant users can connect it through the HA-MCP custom component or another supported setup. The catalogue entries are skills, agents, instructions, settings, and an MCP configuration for working with it.

homeassistant-ai/ha-mcp · 4,654 stars · on GitHub · homeassistant-ai.github.io

Reuse

Borrowing it

Nothing to install: this file belongs to homeassistant-ai/ha-mcp. 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/homeassistant-ai/ha-mcp/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/homeassistant-ai/ha-mcp

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 ha-mcp AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/homeassistant-ai/ha-mcp/agents-md/github.svg)](https://agentmods.dev/instructions/homeassistant-ai/ha-mcp/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/homeassistant-ai/ha-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/homeassistant-ai/ha-mcp/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.

agentmods 80×15 button for ha-mcp AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/homeassistant-ai/ha-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/homeassistant-ai/ha-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 2,867 This file is loaded in full into every session.
When invoked 2,867 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.02867 $0.02867
Opus 5 $0.01434 $0.01434
Sonnet 5 $0.00573 $0.00573
Haiku 4.5 $0.00287 $0.00287

Measured 6d ago against content hash 67c9f3bc6185, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

ha-mcp 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 · 181 lines

How it starts

The opening of the file, as written. The whole thing — 181 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Canonical agent guidance for the Home Assistant MCP Server repository.

Instruction structure

  • AGENTS.md is the canonical source. CLAUDE.md is a symlink to it; edit AGENTS.md only.
  • This root file owns repository-wide behavior, permissions, scope, and testing policy. Linked documents own topic-specific detail.
  • Before working, read every applicable AGENTS.md from the repository root through the target directory; narrower files supplement every broader ancestor.
  • Follow ordinary Markdown links when the task enters their scope. Do not replace them with @imports: imports load every linked byte at startup and defeat progressive disclosure.
  • If linked guidance conflicts with this file's behavioral rules, this file controls. Repair the conflicting duplicate rather than choosing silently.

Repository Structure

This repository uses worktree/ for isolated branches and local/ for scratch data; both are gitignored. Source is under src/ha_mcp/, component code under custom_components/ha_mcp_tools/, tests under tests/, the website under site/, and Home Assistant app flavors under homeassistant-addon*/.

Read the development reference for commands and architecture. Workflow helpers live in .claude/skills/; inspect a helper's own instructions when it is explicitly invoked rather than duplicating its inventory here.

Worktree Workflow

Create feature worktrees under worktree/ from an up-to-date origin/master. A documentation-only adjustment is the sole exception that may be committed directly on master or main:

git fetch origin master
git worktree add worktree/<name> -b <branch> origin/master

Before committing, verify that the working directory is the intended checkout. For a non-documentation change, also verify that the branch is not master/main. Preserve unrelated dirty changes in every checkout. Remove a worktree only when its branch is no longer needed and the user has authorized any associated destructive cleanup. The repository-root checkout is where master is kept; git worktree prune removes stale worktree references.

Read the full file on GitHub · 181 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 Changed · -881 lines · -12,119 tokens per session 67c9f3bc6185
  2. 9d ago First seen · 1,062 lines · 14,986 tokens per session scan A 8e2c30724563

Subscribe to this mod's changes

ha-mcp AGENTS.md is an instructions file published in the GitHub repository homeassistant-ai/ha-mcp (4,654 stars, last pushed today), licensed MIT. It adds 2,867 tokens to every session, about $0.0143 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.

Related

Other instructions, from other repositories

next.js AGENTS.md

AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.

vercel/next.js · 7,296 tokens

codex AGENTS.md

AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

openai/codex · 5,153 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

vscode oss-third-party-notices.instructions.md

Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).

microsoft/vscode · 5,001 tokens

langchain AGENTS.md

AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.

langchain-ai/langchain · 4,469 tokens

spec-kit AGENTS.md

AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.

github/spec-kit · 7,104 tokens