Customize tools
ToolHive lets you customize which tools from a running MCP server are available to your AI clients. This gives you fine-grained control over the capabilities exposed by each server, helping you create focused tool sets and reduce complexity for your AI workflows.
Why customize tools?
Customizing tools helps you:
- Reduce complexity: Hide tools that aren't relevant to your workflow, making it easier for AI clients to select the right tool
- Improve performance: Fewer tools mean faster tool selection and reduced token usage in AI interactions
- Enhance security: Limit exposure to only the tools you need, reducing the risk of unintended actions
- Create focused environments: Tailor tool availability to specific tasks or projects
Tool customization is available only for MCP servers installed from the registry. Custom local and remote MCP servers do not support this feature.
Access tool customization
To customize tools for a running MCP server:
- Open the MCP Servers page.
- Find the server you want to customize and click the menu (︙) on its card.
- Select Customize Tools from the dropdown menu.
The customize tools page displays all available tools from the MCP server, each with a toggle switch and description.
The MCP server must be running to view and customize tools. If the server is stopped when you access the customize tools page, you'll see a message prompting you to start the server first.
Enable or disable tools
On the customize tools page:
- Review the list of available tools and their descriptions.
- Use the toggle switches to enable or disable individual tools:
- Green (enabled): The tool is available to AI clients
- Gray (disabled): The tool is hidden from AI clients
- Click Apply to save your changes.
The ToolHive proxy filters out disabled tools when AI clients connect to the server. Clients only see and can only call the tools you've enabled.
You must keep at least one tool enabled. ToolHive prevents you from disabling all tools on a server, as this would make the server non-functional.
How filtering works
When you customize tools:
- You toggle tools on or off using the switches.
- After clicking Apply, your settings are saved to the server configuration.
- The ToolHive proxy intercepts tool discovery requests from AI clients.
- Only enabled tools appear in the client's tool list.
- If a client attempts to call a disabled tool directly, the proxy blocks the request.
This filtering happens transparently without requiring any changes to your AI client configuration. Your clients automatically see the updated tool list the next time they connect.
If you change tool settings while a client is connected, you may need to restart the client session to see the updated tool list. Some clients cache tool lists and don't automatically refresh.
Example workflows
Focus on specific GitHub operations
If you're using the GitHub MCP server but only need pull request tools:
- Open Customize Tools for the GitHub server.
- Disable all tools except those related to pull requests (like
create_pull_request,get_pull_request,list_pull_requests). - Your AI clients now see only pull request tools, making it easier to work with GitHub PRs without distraction from issue, branch, or repository tools.
Create environment-specific tool sets
If you're running the same MCP server in different groups for different environments:
- Copy the server to multiple groups (see Organize servers into groups).
- Customize tools in each group to match the environment's needs.
- For example, enable only read-only tools in a production group, while allowing all tools in a development group.
Reset to defaults
To restore all tools to their default enabled state:
- Open the customize tools page for the server.
- Manually enable all tools using the toggle switches.
- Click Apply to save your changes.
There is no automatic "reset all" button, but you can quickly enable all tools by toggling each switch and clicking Apply.