Google Threat Intelligence MCP Server

Instructions

Implementation Reference

• gti_mcp/tools/intelligence.py:72-103 (handler)

  The main handler function get_hunting_ruleset decorated with @server.tool(). It takes a ruleset_id parameter, Context, and optional api_key, uses utils.fetch_object to retrieve the hunting ruleset from the VirusTotal API endpoint '/intelligence/hunting_rulesets/{ruleset_id}', and returns the sanitized response.

  @server.tool()
  async def get_hunting_ruleset(ruleset_id: str, ctx: Context, api_key: str = None) -> typing.Dict[str, typing.Any]:
    """Get a Hunting Ruleset object from Google Threat Intelligence.
  
    A Hunting Ruleset object describes a user's hunting ruleset. It may contain multiple
    Yara rules. 
  
    The content of the Yara rules is in the `rules` attribute.
  
    Some important object attributes:
      - creation_date: creation date as UTC timestamp.
      - modification_date (int): last modification date as UTC timestamp.
      - name (str): ruleset name.
      - rule_names (list[str]): contains the names of all rules in the ruleset.
      - number_of_rules (int): number of rules in the ruleset.
      - rules (str): rule file contents.
      - tags (list[str]): ruleset's custom tags.
      
    Args:
      ruleset_id (required): Hunting ruleset identifier.
  
    Returns:
      Hunting Ruleset object.
    """
    async with vt_client(ctx, api_key=api_key) as client:
      res = await utils.fetch_object(
          client,
          "intelligence/hunting_rulesets",
          "hunting_ruleset",
          ruleset_id,
      )
    return utils.sanitize_response(res)

• gti_mcp/utils.py:29-84 (helper)

  The fetch_object helper function used by get_hunting_ruleset to fetch objects from the Google Threat Intelligence API. It handles API errors, builds the request with optional attributes and relationships, and returns the object as a dictionary.

  async def fetch_object(
      vt_client: vt.Client,
      resource_collection_type: str,
      resource_type: str,
      resource_id: str,
      attributes: list[str] | None = None,
      relationships: list[str] | None = None,
      params: dict[str, typing.Any] | None = None):
    """Fetches objects from Google Threat Intelligence API."""
    logging.info(
        f"Fetching comprehensive {resource_collection_type} "
        f"report for id: {resource_id}")
    
    params = {k: v for k, v in params.items()} if params else {}
  
    # Retrieve a selection of object attributes and/or relationships.
    if attributes:
      params["attributes"] = ",".join(attributes)
    if relationships:
      params["relationships"] = ",".join(relationships)
  
    try:
      obj = await vt_client.get_object_async(
          f"/{resource_collection_type}/{resource_id}", params=params)
  
      if obj.error:
        logging.error(
            f"Error fetching main {resource_type} report for {resource_id}: {obj.error}"
        )
        return {
            "error": f"Failed to get main {resource_type} report: {obj.error}",
            # "details": report.get("details"),
        }
    except vt.error.APIError as e:
      logging.warning(
          f"VirusTotal API Error fetching {resource_type} {resource_id}: {e.code} - {e.message}"
      )
      return {
          "error": f"VirusTotal API Error: {e.code} - {e.message}",
          "details": f"The requested {resource_type} '{resource_id}' could not be found or there was an issue with the API request."
      }
    except Exception as e:
      logging.exception(
          f"Unexpected error fetching {resource_type} {resource_id}: {e}"
      )
      return {"error": "An unexpected internal error occurred."}
  
    # Build response.
    obj_dict = obj.to_dict()
    obj_dict['id'] = obj.id
    if 'aggregations' in obj_dict['attributes']:
      del obj_dict['attributes']['aggregations']
  
    logging.info(
        f"Successfully generated concise threat summary for id: {resource_id}")
    return obj_dict

• gti_mcp/utils.py:119-138 (helper)

  The sanitize_response helper function used by get_hunting_ruleset to recursively remove empty dictionaries and lists from the API response.

  def sanitize_response(data: typing.Any) -> typing.Any:
    """Removes empty dictionaries and lists recursively from a response."""
    if isinstance(data, dict):
      sanitized_dict = {}
      for key, value in data.items():
        sanitized_value = sanitize_response(value)
        if sanitized_value is not None:
          sanitized_dict[key] = sanitized_value
      return sanitized_dict
    elif isinstance(data, list):
      sanitized_list = []
      for item in data:
        sanitized_item = sanitize_response(item)
        if sanitized_item is not None:
          sanitized_list.append(sanitized_item)
      return sanitized_list
    elif isinstance(data, str):
      return data if data else None
    else:
      return data

• gti_mcp/server.py:67-73 (registration)

  Creates the FastMCP server instance and imports all tools (including get_hunting_ruleset) via 'from gti_mcp.tools import *', which registers all @server.tool() decorated functions.

  server = FastMCP(
      "Google Threat Intelligence MCP server",
      dependencies=["vt-py"],
      stateless_http=stateless)
  
  # Load tools.
  from gti_mcp.tools import *

• gti_mcp/tools/__init__.py:14-19 (registration)

  The tools module init file that imports from all tool modules including 'from .intelligence import *', exposing the get_hunting_ruleset function for registration when the tools package is imported.

  from .collections import *
  from .files import *
  from .intelligence import *
  from .netloc import *
  from .threat_profiles import *
  from .urls import *