Model Context Protocol (MCP)

MCP (Model Context Protocol) is a protocol that enables LLMs to access custom tools and services. An MCP client (Cascade, in this case) can make requests to MCP servers to access tools that they provide. Cascade now natively integrates with MCP, allowing you to bring your own selection of MCP servers for Cascade to use. See the official MCP docs for more information.

Enterprise users must manually turn this on via settings

Adding a new MCP plugin

New MCP plugins can be added by going to the Settings > Tools > Windsurf Settings > Add Server section.

If you cannot find your desired MCP plugin, you can add it manually by clicking View Raw Config button and editing the raw mcp_config.json file.

When you click on an MCP server, simply click + Add Server to expose the server and its tools to Cascade.

Cascade supports two transport types for MCP servers: stdio and http.

For http servers, the URL should reflect that of the endpoint and resemble https://<your-server-url>/mcp.

We can also support streamable HTTP transport and MCP Authentication.

Make sure to press the refresh button after you add a new MCP plugin.

mcp_config.json

The ~/.codeium/mcp_config.json file is a JSON file that contains a list of servers that Cascade can connect to.

The JSON should follow the same schema as the config file for Claude Desktop.

Here’s an example configuration, which sets up a single server for GitHub:

{
  "mcpServers": {
    "github": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-github"
      ],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "<YOUR_PERSONAL_ACCESS_TOKEN>"
      }
    }
  }
}

It’s important to note that for HTTP servers, the configuration is slightly different and requires a serverUrl field.

Here’s an example configuration for an HTTP server:

{
  "mcpServers": {
    "figma": {
      "serverUrl": "<your-server-url>/mcp"
    }
  }
}

For Figma Dev Mode MCP server, make sure you have updated to the latest Figma desktop app version to use the new /mcp endpoint.

Be sure to provide the required arguments and environment variables for the servers that you want to use.

See the official MCP server reference repository or OpenTools for some example servers.

Admin Controls (Teams & Enterprises)

Team admins can toggle MCP access for their team, as well as whitelist approved MCP servers for their team to use:

MCP Team Settings

Configurable MCP settings for your team.

The above link will only work if you have admin privileges for your team.

By default, users within a team will be able to configure their own MCP servers. However, once you whitelist even a single MCP server, all non-whitelisted servers will be blocked for your team.

How Server Matching Works

When you whitelist an MCP server, the system uses regex pattern matching with the following rules:

• Full String Matching: All patterns are automatically anchored (wrapped with ^(?:pattern)$) to prevent partial matches
• Command Field: Must match exactly or according to your regex pattern
• Arguments Array: Each argument is matched individually against its corresponding pattern
• Array Length: The number of arguments must match exactly between whitelist and user config
• Special Characters: Characters like $, ., [, ], (, ) have special regex meaning and should be escaped with \ if you want literal matching

Configuration Options

Option 1: Plugin Store Default (Recommended)

Leave the Server Config (JSON) field empty to allow the default configuration from the Windsurf MCP Plugin Store.

Admin Whitelist Configuration:

• Server ID: github-mcp-server
• Server Config (JSON): (leave empty)

{}

Matching User Config (mcp_config.json):

{
  "mcpServers": {
    "github-mcp-server": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "-e",
        "GITHUB_PERSONAL_ACCESS_TOKEN",
        "ghcr.io/github/github-mcp-server"
      ],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "ghp_your_token_here"
      }
    }
  }
}

This allows users to install the GitHub MCP server with any valid configuration, as long as the server ID matches the plugin store entry.

Option 2: Exact Match Configuration

Provide the exact configuration that users must use. Users must match this configuration exactly.

Admin Whitelist Configuration:

• Server ID: github-mcp-server
• Server Config (JSON):

{
  "command": "docker",
  "args": [
    "run",
    "-i",
    "--rm",
    "-e",
    "GITHUB_PERSONAL_ACCESS_TOKEN",
    "ghcr.io/github/github-mcp-server"
  ],
  "env": {
    "GITHUB_PERSONAL_ACCESS_TOKEN": ""
  }
}

Matching User Config (mcp_config.json):

{
  "mcpServers": {
    "github-mcp-server": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "-e",
        "GITHUB_PERSONAL_ACCESS_TOKEN",
        "ghcr.io/github/github-mcp-server"
      ],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "ghp_your_token_here"
      }
    }
  }
}

Users must use this exact configuration - any deviation in command or args will be blocked. The env section can have different values.

Option 3: Flexible Regex Patterns

Use regex patterns to allow variations in user configurations while maintaining security controls.

Admin Whitelist Configuration:

• Server ID: python-mcp-server
• Server Config (JSON):

{
  "command": "python3",
  "args": ["/.*\\.py", "--port", "[0-9]+"]
}

Matching User Config (mcp_config.json):

{
  "mcpServers": {
    "python-mcp-server": {
      "command": "python3",
      "args": ["/home/user/my_server.py", "--port", "8080"],
      "env": {
        "PYTHONPATH": "/home/user/mcp"
      }
    }
  }
}

This example allows users flexibility while maintaining security:

• The regex /.*\\.py matches any Python file path like /home/user/my_server.py
• The regex [0-9]+ matches any numeric port like 8080 or 3000
• Users can customize file paths and ports while admins ensure only Python scripts are executed

Common Regex Patterns

Pattern	Matches	Example
.*	Any string	/home/user/script.py
[0-9]+	Any number	8080, 3000
[a-zA-Z0-9_]+	Alphanumeric + underscore	api_key_123
\\$HOME	Literal $HOME	$HOME (not expanded)
\\.py	Literal .py	script.py
\\[cli\\]	Literal [cli]	mcp[cli]

Notes

Admin Configuration Guidelines

• Environment Variables: The env section is not regex-matched and can be configured freely by users
• Disabled Tools: The disabledTools array is handled separately and not part of whitelist matching
• Case Sensitivity: All matching is case-sensitive
• Error Handling: Invalid regex patterns will be logged and result in access denial
• Testing: Test your regex patterns carefully - overly restrictive patterns may block legitimate use cases

Troubleshooting

If users report that their MCP servers aren’t working after whitelisting:

1. Check Exact Matching: Ensure the whitelist pattern exactly matches the user’s configuration
2. Verify Regex Escaping: Special characters may need escaping (e.g., \. for literal dots)
3. Review Logs: Invalid regex patterns are logged with warnings
4. Test Patterns: Use a regex tester to verify your patterns work as expected

Remember: Once you whitelist any server, all other servers are automatically blocked for your team members.

General Information

• Since MCP tool calls can invoke code written by arbitrary server implementers, we do not assume liability for MCP tool call failures. To reiterate:
• We currently support an MCP server’s tools and resources, not prompts.