How to add a custom connector to Claude (and what the free plan allows)

Short answer: on Claude, go to Customize, Connectors, click + Add, then Add custom connector, enter a name and the remote MCP server URL, review the sign-in options and click Add. It works on every plan, including Free, which is limited to one custom connector. Everything below comes from Anthropic's support documentation, checked on 9 November 2026.

What a custom connector is

A custom connector is a remote MCP server you add yourself, for a service that is not in Claude's directory. Claude connects to it from Anthropic's cloud, so you do not install anything on your computer, but the server must be reachable over the public internet. If the idea is new, what is an email MCP server explains it with an example.

Which plans allow it

According to Anthropic's support article:

• Custom connectors using remote MCP are available on Claude, Cowork and Claude Desktop for Free, Pro, Max, Ultra, Team and Enterprise plans.
• Free users can add one custom connector.
• Whether you can add one from the mobile apps is not stated on the page. The connection itself, when it exists, comes from Anthropic's cloud for every Claude client.

Add a connector on Pro, Max or Free

1. Go to Customize, Connectors.
2. Click + Add, then Add custom connector.
3. Enter a name, then the remote MCP server URL, and click Continue.
4. Review the authentication settings Claude detected and change them if needed, then click Continue.
5. Choose an authentication option: Sign in now, Sign in when needed or No sign in.
6. Choose an OAuth client option: Use Claude's published identity (Recommended), Register automatically or Use your own OAuth client. It does not appear if you chose No sign in.
7. If the server does not use OAuth, add fixed credentials (an API key or bearer token) under Request headers. They are stored encrypted.
8. Click Add.

Team and Enterprise

On Team plans, Owners and Primary Owners add connectors. On Enterprise, owners, primary owners and people with a custom role that includes Manage access to Libraries can. They go to Organization settings, Connectors, click Add, hover over Custom, select Web and follow the same steps. Members then go to Customize, Connectors, find the connector (usually labeled Custom) and click Connect.

Use it in a conversation

Click + at the lower left of the chat, then Connectors, and use the toggles to switch it on for that conversation. Anthropic recommends disabling tools you do not need in the Search and tools menu.

Remove or edit one

Go to Customize, Connectors, then click Remove or the three dots next to the connector and follow the prompts. There is no edit: to change a connector, remove it and add it again with the new details.

Worked example: all your mailboxes in one connector

Fezola is a hosted MCP server for Gmail, iCloud, any IMAP mailbox, Google Chat and Telegram. After adding your mailboxes on the Fezola website, add a custom connector named Fezola with the URL https://api.fezola.com/mcp and sign in with OAuth. You land on Fezola's consent screen, which lists the sources Claude will access.

The Free plan's single custom connector is enough here, because Fezola holds all your mailboxes behind one URL. If the sign-in fails with the default OAuth client option, try Register automatically: we support dynamic client registration, but have not tested each option, so tell us what works for you. For the rest of the setup see all your inboxes in Claude.

Safety

• Anthropic does not verify custom connectors. Connect only to servers you trust.
• Review permissions at sign-in and limit scopes where possible.
• Watch for prompt injection in tool inputs and outputs: an email can contain instructions aimed at the model.
• Choose "Allow always" only for trusted servers and tools.
• Research can call connector tools without asking for approval, so disable write-capable tools before using it.

An email connector that cannot send is a safer default: Fezola saves drafts and the direct send tool is off on the server. For the broader picture, read is it safe to connect your email to an AI?.

Troubleshooting

• The server will not connect. It must be reachable from Anthropic's IP ranges: a server on a private network, behind a VPN or blocked by a firewall will fail. Anthropic publishes its IP addresses for allowlisting.
• Another name shows up. If a connector's domain matches a directory listing, Claude may show that service's name and branding instead of Custom.
• Changes do not apply. Remove the connector and add it again.

On ChatGPT, the steps are different: see how to add an MCP server to ChatGPT. To compare options, see best email MCP servers.