Give your bot tools from an MCP server

The MCP server power-up gives your bot tools from a remote Model Context Protocol (MCP) server, such as your own systems or apps that publish an MCP server. You connect the server once for your team, then choose which of its tools each bot can use.

How it works

• The connection belongs to your team. Connect a server once and any bot in the team can use it. You manage connections on the Connections page.
• You sign in, not your visitors. The bot calls the server with the access you granted, for every visitor. Only connect servers you trust, and only enable tools you're happy for any visitor to trigger.
• Every tool starts disabled. You choose which tools the bot can use. Tools the server adds later stay disabled until you enable them.
• Sign-ins stay fresh. Chat Thing renews OAuth access automatically, including for servers a bot hasn't used for a while.
• Tools load live. Chat Thing reads the tool list from the server while the bot chats (refreshed every few minutes), so changes to a tool's description or inputs reach your bot without saving the power-up again.

Chat Thing supports servers that use the Streamable HTTP transport. Servers that only run locally on your computer (stdio) or only use the older SSE transport can't be connected.

Before you start

• Who can do this: team owners and admins.
• The server's MCP endpoint URL, usually ending in /mcp.
• One of these, depending on the server:
  • nothing, for a public server;
  • an account you can sign in with, for servers that use OAuth sign-in;
  • an API key or token, for servers that take one in a header;
  • a client ID and secret, for servers that need you to register an app or use client credentials.

Steps

1. Open your bot, go to the Power-ups tab and click New power-up.
2. Choose MCP server and click Create power-up.
3. Under Server, either choose a server in Use a connected server, or paste the endpoint into Server URL and click Connect.
   • If the server uses OAuth sign-in, a window opens. Sign in and approve access. The window closes when you're connected.
   • If the server needs an API key, expand Authentication, choose API key or token and add the header the server expects, for example Authorization with the value Bearer your-token-here.
4. Under Tools, tick the tools the bot can use. Read-only and Destructive labels show what the server says each tool does. Enable all read-only ticks every read-only tool at once.
5. Optionally, in When should the bot use these tools?, tell the bot when this server is the right place to look, for example "Use for questions about orders, deliveries and returns."
6. Click Save.

Authentication options

Expand Authentication before connecting to choose a method yourself. Automatic works for most servers.

Customise a tool

Click the arrow on an enabled tool to change how the bot uses it.

• Description: replaces the server's description of the tool. The bot reads this to decide when to call the tool, so a clear, specific description helps. Leave it blank to use the server's own.
• Advanced: fixed arguments: for each simple input (text, number, true/false or a fixed list), choose Always use and enter a value. The bot never sees a fixed argument and can't change it, so it's the way to restrict a tool, for example always searching one project or team. Inputs that hold lists or objects can't be fixed.

Tools you've customised show Customised.

Keep the bot focused

Every enabled tool's name, description and inputs are sent to the AI model with every message, which uses tokens and context. The tool list shows how many tokens your selection adds. With many tools enabled, the bot is also more likely to pick the wrong one, so enable only the tools this bot needs. You'll see a warning when the selection gets large.

Manage connections

Click Connections in the sidebar to see every connected service and MCP server in your team, and which power-ups use each server.

• Reconnect signs in again or retries the connection, for example after the server's access expired.
• Edit renames the connection or changes how it authenticates.
• Disconnect deletes the stored credentials. Power-ups that used the server stop giving the bot its tools until you connect a server again in each one.

Check it works

1. Open the bot's test chat.
2. Ask something that needs one of the enabled tools.
3. The reply should use the tool's result. If the bot answers without it, make the tool's description or the power-up's When should the bot use these tools? text more specific.

Troubleshooting

The server shows "Needs reconnecting"

The server rejected Chat Thing's access, usually because a sign-in expired or was revoked. Team owners and admins get an email when this happens. Click Reconnect on the power-up or the Connections page. Until you do, the bot can't use that server's tools.

If the server's sign-in service is only temporarily down, the connection isn't marked: the bot goes without the server's tools until it's back.

"This server doesn't let Chat Thing register itself"

The server needs an app registration. Create an OAuth app in the server's developer settings using the redirect URL shown under OAuth sign-in, then enter its Client ID and Client secret and connect again.

"This server needs authentication but doesn't support OAuth sign-in"

Choose API key or token under Authentication and add the header the server's documentation describes.

A tool says it can't be sent to the AI model

The tool's input definition is too large or isn't valid. It can't be enabled. Ask the server's maintainer to simplify it, or use another tool.

Some enabled tools are no longer on the server

The server removed or renamed them. The bot can't use them; click Remove next to each one, then enable the replacement if there is one.