Borrowing it
Nothing to install: this file belongs to ganhammar/hass-mcp-server. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/ganhammar/hass-mcp-server/main/AGENTS.mdgit clone --depth 1 https://github.com/ganhammar/hass-mcp-serverWrote 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.
[](https://agentmods.dev/instructions/ganhammar/hass-mcp-server/agents-md)<a href="https://agentmods.dev/instructions/ganhammar/hass-mcp-server/agents-md"><img src="https://agentmods.dev/badge/instructions/ganhammar/hass-mcp-server/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.
<a href="https://agentmods.dev/instructions/ganhammar/hass-mcp-server/agents-md"><img src="https://agentmods.dev/badge/instructions/ganhammar/hass-mcp-server/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.01096 | $0.01096 |
| Opus 5.5 | $0.00438 | $0.00438 |
| Sonnet 5.5 | $0.00219 | $0.00219 |
| Haiku 4.5 | $0.00110 | $0.00110 |
Grade A, and why
hass-mcp-server 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.
How it starts
The opening of the file, as written. The whole thing — 87 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Working on this integration
Calling into Home Assistant
Tools live in custom_components/mcp_server_http_transport/tools/. Most reach into
Home Assistant, and not every reach carries the same risk. Three categories, and
they are easy to confuse because they all look like homeassistant.components.*:
- Entity platform contracts. Methods declared on an entity base class that
every integration on that platform implements:
CalendarEntity.async_get_events,async_turn_on, and so on. Safe to call. Home Assistant's own services and REST views are thin wrappers over them. - Cross-integration internals. Module-level functions imported out of another
integration, such as
recorder.statistics.statistics_during_period. No compatibility promise, no deprecation cycle. Prefer a service call. hass.data[DATA_*]lookups. Unsupported, and usually the only way to resolve an entity object. Guard for the component being absent.
Before replacing a private call with a service
Read the handler in core to the end. Three things have to hold, and each has bitten this repo:
The fields. Services routinely return less than the method they wrap.
calendar.get_events filters events through LIST_EVENT_FIELDS and drops uid,
rrule and recurrence_id, which the calendar tools need, so it is not a
substitute for async_get_events.
The response shape. A plain service returns whatever its handler returns, which
is often an envelope rather than the payload. recorder.get_statistics returns
{"statistics": {statistic_id: [rows]}}, not rows keyed by ID. Entity services are
the ones keyed by entity ID, and that keying is added by the helper, not the
handler. Getting this wrong fails silently: the lookup misses and the tool reports
no data rather than an error.
The version it landed in. A service is only supported API on versions that have
it. recorder.get_statistics arrived in 2025.6 and raises ServiceNotFound on
anything older. Check the oldest HA in the CI matrix in .github/workflows/main.yml
before assuming a service is reachable.
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 · +8 lines · +122 tokens per session c6c1c5efc93f
- 2mo ago Changed · +7 lines · +111 tokens per session a1fc7e892e0c
- 2mo ago Changed · +16 lines · +227 tokens per session d4b78ce66f21
- 2mo ago First seen · 56 lines · 636 tokens per session scan A 1ce697ddeee7
hass-mcp-server AGENTS.md is an instructions file published in the GitHub repository ganhammar/hass-mcp-server (84 stars, last pushed 11d ago), licensed MIT. It adds 1,096 tokens to every session, about $0.0044 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 2026-08-30.
hass-mcp-server AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| hass-mcp-server AGENTS.mdganhammar/hass-mcp-server | Instructions file | 84 | 11d ago | MIT | A | 1,096 | Codex, OpenCode |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 9,719 | GitHub Copilot |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 5,516 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | yesterday | MIT | A | 7,461 | Codex, OpenCode |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | today | 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 |