# Devin MCP setup for iCloud Calendar and Outlook

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## Connection and authentication

Use the authentication method shown for each client surface.

| Client surface | Authentication | Setup guide |
| --- | --- | --- |
| Devin | API key | Setup guide available |
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Use Pear tools from Devin with your connected iCloud or Microsoft 365 account. This page configures Devin as a client of Pear.

## 1. Prepare the account

[Sign in to Pear](https://pearmcp.com/login), connect iCloud or Microsoft 365, and create an API key in Settings. In Devin, an organization admin with permission to manage MCP servers adds the custom server.

This guide does not connect you to `https://mcp.devin.ai/mcp`. That address is Devin's own MCP server. It also does not use the Cascade `mcp_config.json` file on the [Windsurf guide](https://pearmcp.com/guides/windsurf). Current Devin and legacy Cascade are different surfaces.

## 2. Add a custom HTTP server

Open Customize → MCPs → Add MCP → Add custom MCP. Choose HTTP (Streamable HTTP). Use an auth header, not OAuth. Pear has not certified a Devin OAuth client.

```text
Transport: HTTP
URL: https://pearmcp.com/api/mcp
Header name: Authorization
Header value: Bearer YOUR_PEAR_API_KEY
```

Check who can use the custom server before entering a key. Devin's Personal/Organization access selector applies to OAuth; it does not make a shared auth-header connection personal. Do not add your personal Pear key to a server other members can invoke. Use the Devin CLI in your private user configuration if the hosted server cannot be restricted to you. Replace the placeholder only in the intended private server settings. Keep the `Bearer ` prefix and the space. Do not paste the key into a Devin chat or a shared screenshot.

The Devin CLI uses the same URL and header in its private MCP config. Devin's OAuth login is a different flow and is not the path on this page.

## 3. Verify a real tool result

Ask Devin to call `pear_provider_status` and name the ready services for the expected account. Then find a known calendar event in a narrow date range and your timezone. Inspect the actual tool response: describing a proposed calendar check is not a completed read.

After the read, try: “Find tomorrow's planning meeting and summarize its time and attendees. Then preview a follow-up email for me to review; do not send it.” Review the draft, recipients, and sending account before approving a write through Pear.

## Troubleshooting and revocation

For authentication errors, check the endpoint, the header name, and that the value starts with `Bearer `. For provider errors, check the connected account in Pear.

Revoke the API key in Pear to end access, then remove the custom server in Devin or replace the header value with a new key.

## Provider limits and next steps

Tools depend on your connected provider, account permissions, and client settings. Start with a read, then inspect a preview before approving writes.

- [iCloud setup](https://pearmcp.com/icloud-mcp-server)
- [iCloud Mail](https://pearmcp.com/ai-icloud-mail)
- [Microsoft 365 setup](https://pearmcp.com/microsoft-365-mcp-server)
- [Outlook Mail](https://pearmcp.com/outlook-mail-mcp)
- [Microsoft To Do](https://pearmcp.com/microsoft-to-do-mcp)
- [Data handling](https://pearmcp.com/data-handling)
- [Plans](https://pearmcp.com/pricing)

Pear's hosted CalDAV connection cannot access Apple's upgraded Reminders store. Only legacy reminder data still exposed through CalDAV is available; reconnecting cannot change this limit. Microsoft To Do is unaffected. Google Workspace is coming soon.

## Sources and compatibility status

Documentation checked on 4 October 2026. Setup guide available; a complete Pear authentication, tool-list, read, and approved-write test in Devin is still pending.

- [Official Devin custom MCP servers](https://docs.devin.ai/work-with-devin/mcp)
- [Official Devin CLI MCP configuration](https://docs.devin.ai/cli/extensibility/mcp/configuration)
- [HTML setup guide](https://pearmcp.com/guides/devin)