How to Build a OnePlan Agent in Copilot Studio for Microsoft Copilot (Custom Agent)

Direct Answer: How to Build a OnePlan Agent in Copilot Studio for Microsoft Copilot (Custom Agent)

In Microsoft 365, OnePlan is added as a Model Context Protocol tool on an agent built in Copilot Studio. Create a confidential app registration in OnePlan under profile avatar > Register Custom Apps, then add the OnePlan MCP Server to your agent in Copilot Studio with OAuth 2.0 > Manual authentication. Copy the callback URL that Copilot Studio generates back into the OnePlan app registration, connect, test, and publish the agent to Microsoft 365 Copilot and Microsoft Teams.

Note: The OnePlan MCP Server is available in preview to approved customers. To request access, contact your Customer Success Manager.

Which Method Should I Use: Connecting Microsoft Copilot to OnePlan

OnePlan supports two ways to connect Microsoft Copilot. This article covers the Copilot Studio custom agent method.

To use the admin connector method, see How to Add OnePlan as a Data Source in Microsoft 365 Copilot (Admin Connector).

Before You Begin: Connecting Microsoft Copilot to OnePlan

Before you begin, make sure you have:

• OnePlan MCP Server preview access approved for your organization
• A OnePlan group administrator to create the app registration
• Copilot Studio and OnePlan open in two browser tabs or windows. You move between them during setup.
• Copilot Studio maker access, with permission to publish agents in your Microsoft 365 tenant
• A Microsoft 365 administrator, if your organization requires agents to be approved in the Microsoft 365 admin center

Note: Copilot Studio uses Power Platform connectors for MCP. If your tenant has Power Platform data loss prevention (DLP) policies, they also apply to the OnePlan tool.

Step-by-Step: Connecting Microsoft Copilot to OnePlan

This setup moves from OnePlan to Copilot Studio, back to OnePlan, and back to Copilot Studio. Copilot Studio shows its callback URL only after you create the tool, so you start the OnePlan app registration with a temporary placeholder and replace it in the third task.

Recommended: Before you start, open Copilot Studio and OnePlan in separate browser tabs or windows, and keep both open until setup is complete. You copy the Client ID and Client Secret from OnePlan into Copilot Studio, then copy the callback URL from Copilot Studio back into OnePlan. Keep the Copilot Studio tool wizard open while you update OnePlan, because you finish the connection in the same wizard. If a different person creates the app registration in OnePlan, have them work alongside you so you can pass these values back and forth.

Task: In OnePlan, Create an App Registration

Follow How to Create an App Registration for the MCP Server in OnePlan with these values:

• Application Name — Microsoft Copilot, or the agent’s name
• Callback URL(s) — https://localhost (temporary placeholder)
• Scope — Group, or Organization to share across groups
• Public client — Cleared. Copilot Studio requires a Client Secret.

Copy the Client ID and Client Secret.

Task: In Copilot Studio, Add OnePlan as a Tool

For Microsoft’s own instructions, see Connect your agent to an existing MCP server.

Starting from Copilot Studio (https://copilotstudio.microsoft.com/):

1. Open your agent or create a new one.

2. Go to Tools, then select Add a tool > Model Context Protocol.

3. Enter the server details:

   • Server name — OnePlan
   • Server description — Search, read, and update OnePlan plans, resources, financials, work items, and approvals. The agent uses this description to decide when to call OnePlan.
   • Server URL — The OnePlan MCP Server address for your region

4. For Authentication, select OAuth 2.0, then Manual. OnePlan doesn’t support dynamic client registration yet, so manual settings are required.

5. Enter the OAuth details, replacing {region} with my, ca, au, or eu:

   • Client ID — From the OnePlan app registration
   • Client secret — From the OnePlan app registration
   • Authorization URL — https://{region}.oneplan.ai/authorize
   • Token URL template — https://{region}.oneplan.ai/token
   • Refresh URL — https://{region}.oneplan.ai/token
   • Scopes — Leave blank

6. Select Create.

7. Copy the Callback URL that Copilot Studio displays.

   

Task: In OnePlan, Update the Callback URL

Starting from any page in OnePlan:

1. Select your profile avatar > Register Custom Apps.

2. Select Edit (pencil icon) on the app registration you created for Copilot.

3. Replace https://localhost with the Copilot Studio callback URL. It must match exactly.

4. Select Update.

Task: In Copilot Studio, Connect and Add the Tool to the Agent

Starting from the Copilot Studio tool wizard:

1. Select Next.

2. On Add tool, select Create a new connection, then sign in to OnePlan and choose your group.

3. Select Add to agent.

Task: Test the Agent

Starting from your agent in Copilot Studio:

1. Open the test pane.

2. Ask: “Show me 5 plans in my OnePlan portfolio.”

3. If prompted, sign in to OnePlan.

Task: Publish the Agent

Starting from your agent in Copilot Studio:

1. Select Publish.

2. Go to Channels and add Teams and Microsoft 365 Copilot.

3. If your organization requires it, have a Microsoft 365 administrator approve the agent in the Microsoft 365 admin center.

4. Share the agent’s name with your users, along with How to Use Microsoft Copilot with OnePlan (OnePlan Agent).

Each user signs in to OnePlan the first time the agent calls a OnePlan tool.

Task: Improve the Agent (Optional)

• Instructions — Add agent instructions, such as “Always preview financial and resource changes before saving. Ask the user to confirm before approving or rejecting approvals.”
• Starter prompts — Add 3 to 5 prompts from MCP Server Use Cases in OnePlan - Overview.

Task: Remove Copilot Access

• To remove OnePlan from the agent: In Copilot Studio, open Tools, select OnePlan, and remove it.
• To stop all Copilot sign-ins to OnePlan: In OnePlan, select Revoke on the app registration under Register Custom Apps.

Why This Matters: Connecting Microsoft Copilot to OnePlan

Context: How a Copilot Studio Agent Reaches OnePlan

Users access OnePlan through the agent your organization publishes to Microsoft 365 Copilot or Microsoft Teams. The published agent calls the OnePlan MCP Server on the user’s behalf using the user’s own OnePlan sign-in, so it can only see and change what that user can see and change.

Context: Why the Callback URL Is a Placeholder at First

Copilot Studio only shows its callback URL after you create the MCP tool. You create the OnePlan app registration with a temporary placeholder, then replace it with the real callback URL once Copilot Studio generates it.

Frequently Asked Questions: Connecting Microsoft Copilot to OnePlan

Q: Why does sign-in fail with a redirect error when connecting Copilot to OnePlan? A: In OnePlan, the callback URL on the app registration must match the callback URL Copilot Studio shows, exactly. Select Edit on the app registration under Register Custom Apps and paste the URL again.

Q: Why does Copilot Studio need a Client Secret for OnePlan? A: Copilot Studio Manual OAuth requires a Client Secret. In OnePlan, create the app registration as a confidential client by leaving Public client cleared.

Q: Do Power Platform DLP policies apply to the OnePlan tool in Copilot Studio? A: Yes. Copilot Studio uses Power Platform connectors for MCP, so your tenant’s data loss prevention (DLP) policies also apply to the OnePlan tool.

What to Do Next: Connecting Microsoft Copilot to OnePlan

Get started with related tasks:

• How to Use Microsoft Copilot with OnePlan (OnePlan Agent)
• How to Manage Custom Apps in OnePlan

Use another Microsoft Copilot configuration method:

• How to Add OnePlan as a Data Source in Microsoft 365 Copilot (Admin Connector)

Learn about related topics:

• MCP Server Use Cases in OnePlan - Overview
• MCP Server in OnePlan - Frequently Asked Questions
• MCP Server Configuration in OnePlan - Guided Workflow
• Microsoft: Connect your agent to an existing MCP server