Deno Gemini Grounding

You run a Gemini-grounding MCP server locally to let a client send prompts to Gemini and receive grounded responses. It acts as a bridge between your environment and Gemini, enabling you to perform specialized tasks like Connpass data queries and event insights through an MCP client. This guide walks you through practical usage, installation, and important notes so you can run and integrate the server smoothly.

How to use

Start by running the MCP server in a way that fits your workflow, then configure your MCP client to talk to it. The server is designed to respond to the client’s tool invocations and return grounded results from Gemini-based prompts. You can run it in a container or directly in your environment, and you typically use the client’s tool list to call specific capabilities such as Connpass user data, groups, and events.

How to install

Prerequisites you need before starting:

• A runtime capable of executing the MCP server (Docker is supported for clean setup; you can also run with Deno or Node.js as described in the examples).
• Docker installed on your system if you plan to use the container-based workflow.
• Access to a Connpass API key if you intend to fetch Connpass data.
• A suitable MCP client configured to communicate with your MCP server (see the client config example).

Step-by-step commands to set up and run the server using Docker (recommended for a clean, isolated setup):

# 1. Create an environment file with your Gemini API key if required by your setup
# (example not always required, shown for completeness)
echo GEMINI_API_KEY=XXXXXX > .env

# 2. Build and start the MCP server using Docker
# This will pull dependencies and start the service in a container
./start.sh

# 3. When finished, stop and remove containers
docker compose down

If you prefer not to use Docker, you can start the server with Deno or Node.js according to the environment setup you choose. Examples include starting via a Deno task or building with Node.js and running the built entry, but you should follow the exact runtime command shown in your configuration for MCP. The important part is to ensure you provide the necessary flags for network, read, and env access as needed by your environment.

Additional sections

Configuration and runtime notes to keep in mind:

• Environment variables and security: file read, environment access, and network access are controlled by runtime flags (for Deno, these include --allow-read, --allow-env, --allow-net). These controls are active for local execution and do not apply to remote usage.
• Testing: you can run tests to validate the Gemini grounding prompts, for example using tasks like deno task test:tokyo or deno task test:google_search to verify responses and performance.
• WSL considerations: running the MCP client on WSL with certain tooling may require Windows-side execution for compatibility. Use Windows for the MCP client if recommended for your setup.
• Test-driven integration: after your tests pass, update your client’s Gemini grounding settings to point to your MCP server, and ensure the client uses proper MCP command mappings so prompts are routed correctly to the server.

Example MCP client configuration (stdio mode) to invoke the local server via Docker. This configuration starts the MCP server container and connects through Docker to expose the server’s stdin/stdout for interactive communication. Replace the API key with your actual Gemini API key.

{
  "mcpServers": {
    "deno-gemini-grounding-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": [
        "run",
        "-e",
        "GEMINI_API_KEY=XXXXXXXXXXXXXXXX",
        "deno-gemini-grounding-mcp-server"
      ],
      "env": [
        {
          "name": "GEMINI_API_KEY",
          "value": "XXXXXXXXXXXXXXXX",
          "description": "Gemini API key used by the MCP server",
          "required": true
        }
      ]
    }
  }
}

Available tools

get_connpass_user_list

Fetch basic information about Connpass users, including participation, management, and bookmark events.

get_connpass_user_group_list

Retrieve the groups that a Connpass user belongs to, including names, URLs, and descriptions.

get_connpass_user_events

Obtain events that a Connpass user has attended, with names, dates, locations, and URLs.

get_connpass_user_presenter_events

List events where a Connpass user participated as a presenter, with details and descriptions.