Use SphereHarness from Microsoft Copilot

Ask your CAD questions in a Microsoft Copilot agent. Copilot asks, your own PC does the CAD work, and the result comes back to Copilot. The request is relayed through SphereHarness and never stored.

New to channels? Read Channels & Messaging first. You need the desktop agent version 1.3.5 or later on your PC, a SphereHarness account with an active licence or trial, and a Microsoft Copilot agent you can edit (for example in Copilot Studio).

What it does

• You add one SphereHarness address to your Copilot agent: https://sphereharness.io/mcp.
• You sign in once with your SphereHarness account. Nothing is registered in Microsoft Entra, and no administrator consent is needed.
• When Copilot needs your CAD, it sends the request to SphereHarness. We check the sign-in and your licence, and pass the request to the desktop agent on your PC. Your PC runs it with your CAD system and sends the result back.
• The AI that reads your question is Microsoft Copilot. SphereHarness runs no AI for this.

Set it up in three steps

1. Turn it on in the desktop agent. On your PC open Settings → Channels → Microsoft Copilot via SphereHarness and switch it on. The agent then keeps a connection to SphereHarness so Copilot’s requests can reach it. Keep the agent running.

2. Add SphereHarness to your Copilot agent.

   • Copilot Studio: open your agent → Tools → Add a tool → New tool → Model Context Protocol. Give it a name and a short description, and enter the server URL https://sphereharness.io/mcp. For authentication choose OAuth 2.0 → Dynamic discovery. Select Create, then Create a new connection and sign in with your SphereHarness account. Then add the tool to the agent. Generative orchestration must be on for the agent.
   • Microsoft 365 declarative agents (Agents Toolkit): add an action that starts from an MCP server, enter the same URL, and choose OAuth (dynamic registration).

   At the sign-in page you see which Copilot agent asks, and your SphereHarness licence. Choose Allow. Without an active licence or trial the sign-in is refused and says why.

3. Allow once on the PC. The first time Copilot reaches a PC, that PC asks: “Microsoft Copilot … wants to use this PC – Allow / Not me”. Allow runs the request. Not me refuses it. Each PC asks once for each Copilot connection.

Then ask Copilot, for example: “Which CAD sessions are running on my PC?” or “What is the mass of the open part?”

Copy the MCP guide for your agent

Use another agent (Claude, ChatGPT, Copilot Studio, VS Code …)? Copy this guide, paste it into your agent’s chat and ask it to connect to SphereHarness through MCP. It holds no secret and nothing about you.

Copy MCP guide

SphereHarness - connect through MCP

WHAT IT IS
SphereHarness lets an AI agent work with the CAD systems installed on the user's PC. The AI runs in YOUR agent (the one you are using now). The CAD work is done by the SphereHarness desktop agent on the user's own PC. SphereHarness only relays the calls.

ENDPOINT
https://sphereharness.io/mcp
Transport: Streamable HTTP (a remote MCP server; no local process to start).

AUTHENTICATION
OAuth 2.0/2.1. The client discovers everything itself:
- /.well-known/oauth-protected-resource
- /.well-known/oauth-authorization-server
It uses dynamic client registration and PKCE. The user signs in with their SphereHarness account in the browser and chooses Allow. There are no API keys to create or paste.

TOOLS (five)
- cad_sessions: list the CAD sessions running on the user's PC. Call this first.
- cad_list_operations: list or search the operations available for a CAD system.
- cad_describe_operation: show one operation's parameters (all lengths in mm).
- cad_execute: run one operation on a CAD session.
- cad_screenshot: save a picture of the CAD window on the PC and return its file path.
Working order: cad_sessions, then cad_list_operations, then cad_describe_operation, then cad_execute. Check the result by reading the model back (mass properties, dimensions, feature tree); do not trust a success message alone.

RULES
- Read, measure and report operations, and a few simple builds (new part, sketch, extrude, hole, dimension), are allowed.
- Delete, Close, SaveAs, Export, Suppress and Rename operations are refused.
- A step that changes the user's work still needs the user's click on the PC.
- The user's SphereHarness licence or trial is checked on every call.
- Requests and results are relayed through SphereHarness and never stored.
- The SphereHarness desktop agent 1.3.8.7 or later must be running on the PC with "Microsoft Copilot via SphereHarness" switched on (Settings, Channels). The first connection asks once on the PC: Allow / Not me.
- One call has about 90 seconds.

SET-UP BY CLIENT (use the endpoint above)
- Copilot Studio: Tools, Add a tool, New tool, Model Context Protocol. Enter the URL. Authentication: OAuth 2.0, Dynamic discovery. Create a connection and sign in.
- Microsoft 365 declarative agent: Agents Toolkit, add an action from an MCP server, enter the URL, OAuth with dynamic registration.
- Claude Code: claude mcp add --transport http sphereharness https://sphereharness.io/mcp   then run /mcp and sign in.
- Claude desktop or claude.ai: add a custom connector with the URL and sign in.
- ChatGPT: add a connector (custom MCP) with the URL, authentication OAuth.
- VS Code, Cursor and other MCP clients: add an HTTP MCP server with the URL; the client handles the OAuth sign-in.
Caveat: a client that cannot register itself needs a client pre-registered by SphereHarness support.

Paste this into your agent and ask it to connect to SphereHarness through MCP.

What Copilot can and cannot do

A step that changes your work still needs your click on the PC, as it always does. If your PC waits for your approval, Copilot waits too. A picture is not sent to Copilot in this version: you get the file path on your PC.

Licence

Your SphereHarness licence or trial is checked on every request. If it has ended, Copilot is told so and nothing reaches your PC. The CAD add-in also keeps its own seat check for each operation.

Several PCs and a PC that is off

• With the switch on in more than one PC, the request goes to your PC that was used last, or to the only one connected. With several and none chosen, Copilot asks which: choose one under Settings → Channels → Use this PC.
• If none of your PCs is connected, Copilot is told: “Your PC NAME is not connected to SphereHarness right now. Start the SphereHarness agent there and ask again.” Nothing is queued on our server.
• One request has about 90 seconds. Copilot Studio itself stops a tool call at about two minutes, so long jobs are better started in the chat on your PC.

Connected apps and revoke

Each Copilot agent you allowed is a connected app. See them in the desktop agent under Settings → Channels → Microsoft Copilot via SphereHarness → Connected apps, and select Revoke on a row. The connection stops at once; the next request from that Copilot agent is refused, and you sign in again to reconnect. Turning the switch off in step 1 stops this PC receiving Copilot requests. Deleting your SphereHarness account removes all sign-ins.

What passes through our servers

• Passes through, in memory only: the request (the tool name and its arguments) and the result text. It is forgotten as soon as the request is answered, and when our server restarts.
• Never written to our database, our disk or our logs: no request, result, picture or file.
• Kept: your sign-in for each connection (which Copilot agent, your user, when it was allowed and last used, a hashed renewal token), and audit entries with identifiers, the tool name, the outcome and the time it took — never the arguments or the result.
• Microsoft handles your conversation with Copilot, under your organisation’s agreement with Microsoft. Where every kind of data goes: What goes where.

Troubleshooting

Related

• Channels & Messaging
• Microsoft Teams · WhatsApp · Telegram
• What goes where — every data flow
• Verifying Results — always confirm geometry, never trust the wording of a reply