Claude connector vs plugin vs MCP URL: what's the difference?

01The four options at a glance

There are four ways to give Claude a tool, and they differ in where they come from, which plans include them and where they run.

Sources: Anthropic's help on connectors, custom connectors, labels, plugins and local MCP servers.^{[1][2][3][4][5][6][7]}

02What a connector does in Claude

A connector lets Claude read data from a service and take actions in it, using the permissions of the person who connects it. If you cannot open a file or record in the source system, Claude cannot reach it through the connector either.^[1] The exception is a custom connector that uses a shared credential such as an API key: it reaches whatever that credential can access.^[1]

Web connectors are brokered through Anthropic's cloud, even when you use Claude Desktop or Cowork on your own machine. That means the MCP server has to be reachable from the public internet. A server behind a VPN or a corporate firewall will not connect unless Anthropic's IP ranges are allowlisted.^[2]

On Team and Enterprise, an Owner first adds the connector for the organization. That alone gives nobody access: in the standard flow, each person then connects their own account. With Enterprise-managed auth, in beta for Team and Enterprise, the organization authorizes a connector once and access is inherited on first login; connectors with shared credentials use those credentials.^[1] In a chat, you turn connected services on or off for that conversation with + > Connectors.^[1] For a mailbox example, see connect Gmail to Claude.

03Directory or your own URL: same technology, different label

Anthropic says connectors in the directory and custom connectors you add yourself use the same technology. If you have a connector's URL, you can add it as a custom connector whether or not it is listed.^[3] Listing makes a connector discoverable and gives it a review label, but it does not change the tools it exposes.^[3]

The directory uses three labels:^[3]

• Verified: Anthropic tested the connector's tools for quality and compatibility. Anthropic is explicit that this is not a security audit or a guarantee, and that the developer can change the tools after review.
• Community: a third-party developer built it. Anthropic screened it before listing but did not review it in depth, and Claude shows a reminder before you connect it.
• Custom: you added it yourself, and Anthropic has not reviewed it.

New submissions are listed as Community by default. There is no application for Verified; Anthropic escalates listings it rates as highly useful on its own.^[3] The label affects how a connector is shown and found. Once connected, a Community connector has the same capabilities and access as any other connector you grant.^[3]

How to add a custom connector

On an individual Pro or Max plan:^[2]

1. Go to Customize > Connectors.
2. Click + Add, then Add custom connector.
3. Enter a name and the remote MCP server URL, then click Continue.
4. Review the authentication settings Claude detected and click Continue.
5. Under Authentication, choose an option such as Sign in now. Under OAuth client, keep Use Claude's published identity (Recommended).
6. Click Add.

If a server authenticates with an API key or bearer token instead of OAuth, you can add it as a request header.^[2] Free users can add exactly one custom connector.^[2] On Team plans only Owners and Primary Owners can add custom connectors; on Enterprise, people with a custom role that includes Manage access to Libraries can too.^[2] You cannot edit a custom connector; remove it and add it again with the new details.^[2]

04What a plugin is in Claude

A plugin packages skills, commands, MCP connectors and agents so you can add them as one unit.^[5] It is saved to your account, which makes it available in Cowork and Claude Code without installing it again.^[5] Anthropic offers plugins on the paid plans: Pro, Max, Ultra, Team and Enterprise.^[4]

You add plugins from Customize > Plugins in three ways: from Discover, with Add > Add marketplace using a Git repository, or with Add > Upload plugin for a .zip or .plugin file.^[5] Anthropic runs automated validation and a security scan on every version of a directory plugin, and a person reviews each new listing before it goes live. That review does not cover a plugin you add from a marketplace URL or upload yourself.^[5]

Source: Anthropic's plugin docs.^[5]

A plugin does not sign you in to anything

Adding a plugin does not add a connector to your account or sign you in to a service.^[5] The plugin's Connectors tab shows each bundled service as Connected, Not connected or Not added, and you connect it from there.^[5] The plugin's skills load either way, but a skill that needs a service cannot reach it until its connector shows Connected.^[5]

The reverse also holds: removing a plugin that packages skills and a connector does not disconnect the connector, so you disconnect it separately.^[8] Some plugin parts run on your computer, such as hooks, agents and local MCP servers. Those work in Cowork and Claude Code, not in chat.^[4][5][6]

Plugins in Claude Code

Claude Code v2.1.273 or later syncs the plugins on your Claude account when you sign in with that account. It does not sync them when you sign in with an API key or run on a cloud provider such as Amazon Bedrock.^[4] Plugins you install from the Claude Code command line stay on that machine and are not added to your claude.ai account.^[5] To add a marketplace there, run /plugin marketplace add with the GitHub repository as owner/repo.^[10]

05What an MCP URL is

An MCP URL is the address where a remote MCP server answers; for Command Mail that is https://commandmail.app/mcp. On the web and in the desktop app you paste it into a custom connector.^[2] In Claude Code you add it from the shell:^[9]

claude mcp add --transport http <name> <url>

The Claude Code docs say directory connectors use the same MCP infrastructure, so you can add any remote server listed there with claude mcp add.^[9] Some Anthropic-hosted connectors, including Microsoft 365, Gmail and Google Calendar, don't support local OAuth from Claude Code. If you already added such a server locally, remove that entry with claude mcp remove <name> and connect the service on claude.ai. The connector then appears automatically in Claude Code when you sign in with the same Claude account.^[9] When a server's instructions only give a launch command or a JSON block written for Claude Desktop, the same docs explain how to convert it.^[9] For the basics, see what is an MCP server?.

06Desktop extensions and local MCP servers

If a tool runs on your computer, such as access to local files or a database on localhost, a desktop extension is the right fit. Desktop extensions run only in Claude Desktop and Claude Code, not on the web or mobile.^[6] You install one under Settings > Desktop app > Manage next to Extensions, either from the directory or from your own .mcpb file.^[7]

Local MCP servers you configure by hand in claude_desktop_config.json use your local network, but they are not available in Cowork or on claude.ai.^[2]

07The new Plugins page replaces Customize

Anthropic is merging plugins, skills and connectors into one Plugins experience. In the sidebar, Customize becomes Plugins, and one Plugins page replaces the separate Skills, Connectors and Plugins tabs.^[8] Free, Pro, Max, Ultra and Team plans started rolling out on October 29, with general availability planned for November 9; Enterprise gets it on November 30, 2026.^[8]

Your existing connectors, skills and plugins stay installed. On the new page you can filter by skills or connectors, and each card shows its type.^[8] Where this article says Customize, your account may already say Plugins. One rule changes for Team and Enterprise: from November 30, if Skills are turned off for the organization, plugins are blocked in the desktop app as well.^[8]

08Which option fits which job

The choice depends on where the tool runs and whether you need more than one connection.

• The service is in the directory: use the directory connector. It works wherever you use Claude.^[6]
• The service has a public MCP URL but no listing: add a custom connector. On Free it takes your single slot.^[2]
• You want a ready-made workflow with instructions and the right service: add a plugin on a paid plan, then connect its connectors one by one.^[4][5]
• The tool only runs on your computer: install a desktop extension.^[6]
• You work in the terminal: in Claude Code, use claude mcp add for a server or /plugin for a plugin.^[9][10]

09What a label does not protect you from

A review label does not limit what a connector's tools can do. For any third-party connector, Anthropic advises connecting only to servers you trust, reviewing the permissions requested at sign-in and watching for prompt injection.^[2][3] Read Claude's tool approval requests and choose Allow always only for tools you trust to run unsupervised.^[2]

During Research, Claude can call tools from your connectors without further approval, so Anthropic recommends turning off tools that write to other apps.^[2] On Team and Enterprise, Owners can also set organization-wide which actions of a connector are always allowed, need approval or are blocked, such as searching and summarizing email but not sending it.^[1]

10Connecting Command Mail to Claude

You can add Command Mail to Claude in all three ways, and each time you choose at sign-in which permissions the agent gets.^[11]

• From the directory: Command Mail is listed as a Community connector in the Claude directory.^[11][12]
• By MCP URL: add https://commandmail.app/mcp as a custom connector, or in Claude Code run claude mcp add --transport http commandmail https://commandmail.app/mcp. Sign-in uses OAuth 2.1 with PKCE, so no API key is needed.^[11]
• As a plugin: our public repository FYN-Labs/commandmail-plugin contains a Claude marketplace with the same MCP URL and four skills for setup, a recurring inbox routine, cleanup and everyday mail work. In Claude Code, run /plugin marketplace add FYN-Labs/commandmail-plugin and then /plugin install command-mail@commandmail.^[13] We have not tested adding it as a marketplace in Claude on the web.
• Permissions instead of full access: every permission can be switched off when you connect, sending without approval starts switched off, and mail:send-approved sends exactly the draft revision a person approved.^[11]

On Command Mail's Free plan the agent reads, searches, sorts and drafts but cannot send; sending starts with Pro.^[11] The permissions documentation explains every permission and autonomy level. To add an MCP server in Claude Code, Codex or Cursor step by step, see Email in Claude Code, Codex and Cursor.

11Sources and date

As of 2026-11-02. Anthropic's help articles and docs were retrieved that day, and menu names follow the English versions. The Claude directory page blocks automated requests and was read through a reader proxy. Statements about Command Mail rely on llms.txt, the plugin repository at commit 5c91ce4 and the app code at commit 60c8c3d. We have not run the plugin install in Claude on the web ourselves.

You can start for free and connect Command Mail to Claude with read access only at first.

Frequently asked questions

Sources

1. Anthropic: Use connectors to extend Claude's capabilities support.claude.com, accessed November 2, 2026
2. Anthropic: Get started with custom connectors using remote MCP support.claude.com, accessed November 2, 2026
3. Anthropic: Connector verification (Verified, Community, Custom) claude.com, accessed November 2, 2026
4. Anthropic: Use plugins in Claude support.claude.com, accessed November 2, 2026
5. Anthropic: Plugins (Claude Docs) claude.com, accessed November 2, 2026
6. Anthropic: When to use desktop and web connectors support.claude.com, accessed November 2, 2026
7. Anthropic: Getting Started with Local MCP Servers on Claude Desktop support.claude.com, accessed November 2, 2026
8. Anthropic: Manage plugins, skills, and connectors from one Plugins page support.claude.com, accessed November 2, 2026
9. Claude Code Docs: Connect Claude Code to tools via MCP code.claude.com, accessed November 2, 2026
10. Claude Code Docs: Discover and install plugins code.claude.com, accessed November 2, 2026
11. Command Mail: llms.txt commandmail.app, accessed November 2, 2026
12. Claude directory: Command Mail claude.ai, accessed November 2, 2026
13. GitHub: FYN-Labs/commandmail-plugin github.com, accessed November 2, 2026