# WattScope

**Estimated carbon footprint of your team's AI usage** — a remote
[MCP](https://modelcontextprotocol.io) connector for Claude and other MCP
clients.

Ask Claude to record a piece of work and WattScope attributes it to your
organisation and to a project, then reports the estimated footprint back
whenever you ask — per session, per project, or across the whole organisation.

There is one URL, no API key, and nothing to paste into a configuration file:

```
https://www.wattscope.com.au/mcp
```

---

## ⚠️ Read this before trusting any number

Every figure WattScope produces is an **order-of-magnitude estimate, not a
measurement**, and two independent limits apply.

**The server cannot see your conversation.** An MCP server receives only the
tool calls made *to* it — there is no visibility into the surrounding
Claude session's own token usage. Usage must be recorded deliberately; anything
not recorded is not counted. That is a design constraint, not a roadmap item.

**The emission factors are estimates.** Providers do not publish per-token
energy figures for hosted models, so the factor table infers them from public
analyses of whole-query energy use. They are uncertain by a factor of several
in either direction.

Every tool response carries a `disclaimer` field saying so. **Do not use these
outputs for regulatory reporting, public environmental claims, or offset
retirement volumes.**

What makes the numbers usable anyway is that WattScope grades them. Token
counts reconcilable against a vendor's own usage API, counts a client's
instrumentation exported as the work happened, and counts a person entered by
hand are three different kinds of claim, and they are reported separately
rather than blended into one confident-looking total.

---

## Connect

Full step-by-step, always current: **<https://www.wattscope.com.au/connect>**

### Claude Desktop and claude.ai

`Customize` → `Connectors` → `+` → name it **WattScope**, paste the URL → `Add`.

Claude sends you to wattscope.com.au to sign in and approve. An account is
created on first sign-in — there is nothing to set up beforehand.

Works on Free, Pro, Max, Team and Enterprise. On the free plan you can have one
custom connector at a time.

### Claude Team and Enterprise

Members cannot add connectors themselves. An Owner adds it once for everyone:

`Organization settings` → `Connectors` → `Add` → `Custom` → `Web`.

Each member still signs in individually the first time, so usage stays
attributed to the person who incurred it.

### Claude Code

```bash
claude mcp add --transport http wattscope https://www.wattscope.com.au/mcp
```

Then `/mcp` → **wattscope** → Authenticate. To share it with a repository
instead, commit an `.mcp.json` at the project root:

```json
{
  "mcpServers": {
    "wattscope": {
      "type": "http",
      "url": "https://www.wattscope.com.au/mcp"
    }
  }
}
```

### Cursor

`~/.cursor/mcp.json`:

```json
{
  "mcpServers": {
    "wattscope": {
      "url": "https://www.wattscope.com.au/mcp"
    }
  }
}
```

### VS Code

`.vscode/mcp.json`:

```json
{
  "servers": {
    "wattscope": {
      "type": "http",
      "url": "https://www.wattscope.com.au/mcp"
    }
  }
}
```

### Codex CLI and IDE

`~/.codex/config.toml`:

```toml
[mcp_servers.wattscope]
url = "https://www.wattscope.com.au/mcp"
```

Then `codex mcp login wattscope`.

> Codex has not been driven end to end against WattScope. The protocol and the
> sign-in flow are the same ones Claude uses, so it is expected to work — but
> expected is not verified. If it does not,
> [tell us](https://www.wattscope.com.au/support) rather than assuming it is
> you.

---

## Things to ask for

You do not call these tools yourself; you describe what you want and Claude
chooses. Phrasings that work:

- "Start tracking a new session for the reef survey project."
- "Record that as 40,000 input and 8,000 output tokens on Sonnet."
- "What has this session cost in carbon so far?"
- "Show me the whole organisation's footprint this month, split by how well
  evidenced it is."
- "Which of our projects is using the most, and how confident are those
  numbers?"

A session is a piece of work, not a conversation. It lasts until you start
another one, so usage recorded across several chats about the same job stays
together.

---

## Tools

Eleven tools. Every one declares a `title` and the applicable `readOnlyHint` /
`destructiveHint`; none is destructive, and none reaches outside the service.

| Tool | | What it does |
| --- | --- | --- |
| `server_info` | read | Version, active org, session and project, factor set |
| `get_session_footprint` | read | Footprint recorded during this session |
| `get_project_footprint` | read | One project's total across sessions |
| `list_projects` | read | Every tracked project, heaviest first |
| `org_footprint` | read | The whole organisation's footprint (admin only) |
| `get_offset_options` | read | Indicative offset pricing — purchasing is not available |
| `start_session` | write | Start a new tracked session |
| `set_project` | write | Set the project subsequent usage counts toward |
| `set_active_org` | write | Switch which org tool calls operate on |
| `record_usage` | write | Record the footprint of AI model usage |
| `record_chat_estimate` | write | Estimate a Claude Desktop chat from character counts |

Two prompts: `track_usage` and `carbon_report`.

---

## Your data

WattScope holds no credential for any other service. Each organisation's data
is reachable only by that organisation — every tool call is scoped to the
caller's authenticated org, and there is no parameter that widens it.
Conversation content is never received, because an MCP server is not sent it.

Authentication is OAuth 2.0 with Dynamic Client Registration and PKCE. There is
no API key to issue, lose, or rotate.

- [Privacy policy](https://www.wattscope.com.au/privacy)
- [Terms](https://www.wattscope.com.au/terms)
- [Support and security contact](https://www.wattscope.com.au/support)

---

## About this repository

This repo is the **public listing and distribution artifact** for WattScope: the
connect instructions, the icons, the
[MCP Registry](https://registry.modelcontextprotocol.io) manifest, and the
Claude plugin. It deliberately contains no server source — WattScope is a hosted
service, and the server is not open source.

Registered in the official MCP Registry as `au.com.wattscope/wattscope`.

The documentation and configuration snippets here are MIT-licensed so you can
copy them freely. The WattScope name and logo are not — see [NOTICE](NOTICE).

---

WattScope Pty Ltd · ABN 26 702 095 743 · <https://www.wattscope.com.au>