# Australian Heat Pump Hot Water Rebate & Payback

> Heat pump vs gas hot water (AU): rebate stack, net outlay and payback verdict by postcode.

- name: ai.sourcemill/au-hot-water-payback
- version: 0.1.1
- connection class: R0 (autonomous)
- trust: 80/100 flags: no-repository
- quality: 79/100 (good)
- owner: not claimed
- descriptor: https://api.protogrid.dev/v1/servers/ai.sourcemill%2Fau-hot-water-payback
- tools: https://api.protogrid.dev/v1/servers/ai.sourcemill%2Fau-hot-water-payback/tools

**An agent can connect right now, no human step.** Remote endpoint, no authentication, reachable on the last probe.

## Connection (mcpServers)

```json
{
  "mcpServers": {
    "au-hot-water-payback": {
      "type": "http",
      "url": "https://heatpump.sourcemill.ai/mcp"
    }
  }
}
```


## Trust

- hygiene: 80
- liveness: 100
- freshness: 85
- provenance: 55
- drivers: +dns-namespace +website +reachable +uptime-99% ~updated-89d-ago -no-repository
- Derived from observable signals (official registry feed and our own credential-free probes); no code audit performed.

## Quality 79/100 (good)

### protocol: 75 (weight 25)

- warn `protocol.modern`: newest supported version is 2024-11-05; 2026-07-28 not supported, older versions are deprecated until 2027-07-28
- n/a `protocol.stateless`: only applies to 2026-07-28 servers
- pass `protocol.transport`: streamable HTTP
- n/a `protocol.list_ttl`: only applies to 2026-07-28 servers

### authorization: n/a (weight 15)

- n/a `auth.prm`, `auth.as_metadata`, `auth.cimd`: no remote uses OAuth
- n/a `auth.secret_in_url`: no templated URL

### tool hygiene: 71 (weight 30)

- pass `tools.descriptions`: every tool has a description
- pass `tools.description_length`: descriptions are concise
- pass `tools.schemas`: every tool has an object input schema
- fail `tools.annotations`: no tool declares readOnlyHint or destructiveHint, so clients cannot tell safe calls from risky ones
- fail `tools.directory_hints`: no tool declares all four of readOnlyHint, destructiveHint, idempotentHint and openWorldHint; missing: check_hot_water_switch (readOnlyHint, destructiveHint, idempotentHint, openWorldHint)
- pass `tools.token_cost`: about 543 tokens to load every tool
- pass `tools.api_dump`: tools are not a one-to-one API dump

### stability: 100 (weight 15)

- pass `stability.changes`: no tool changes in 30 days
- pass `stability.rug_pull`: no tool changed its meaning under the same name

### dependencies: n/a (weight 15)

- n/a `deps.known_vulns`, `deps.mcp_sdk_version`, `deps.resolvable`: no npm or PyPI package

- tools: 1, about 543 tokens to load them all
- tool set hash: fbbb221c64e8caa941263339ea2a8c54
- badge: [![protogrid quality](https://protogrid.dev/badge/ai.sourcemill/au-hot-water-payback.svg)](https://protogrid.dev/servers/ai.sourcemill/au-hot-water-payback)
- Checks run on what our credential-free, read-only probes observe; tools are never called and no code audit is performed.

### Tool changes

_No tool definition changes recorded._

## Remotes

- https://heatpump.sourcemill.ai/mcp (streamable-http, auth none, reachable true, uptime30d 0.9915254)

## Packages

_none_

## Tools (1)

- `check_hot_water_switch`: Use when someone asks whether a heat pump hot water system is worth it in Australia, which rebates they can stack, how much a heat pump costs after rebates, or how long it takes to pay off — including "can I combine the STC rebate with Victorian Energy Upgrades or Solar Victoria", "do I qualify", and "is a heat pump cheaper to run than gas". Given a postcode, the current hot water system and a few household facts, returns the rebates actually stackable at that postcode (with each scheme's eligibility gates and source), the net-of-rebate outlay, the payback period, and which term — rebates, the avoidable gas supply charge, the energy saving, or a replacement you were buying anyway — is really carrying the decision. Modelled estimate, not financial advice.