Bing Search MCP Server

Instructions

Args:
    query: Search query (required)
    count: Number of results (1-50, default 10)
    offset: Pagination offset (default 0)
    market: Market code like en-US, en-GB, etc.

Implementation Reference

• mcp_server_bing/server.py:94-159 (handler)

  The core handler function for the 'bing_web_search' tool. It is registered via the @server.tool() decorator. The function signature with type annotations defines the input schema. It performs the Bing web search API call, applies rate limiting, handles errors, and formats search results as a string.

  @server.tool()
  async def bing_web_search(
      query: str, count: int = 10, offset: int = 0, market: str = "en-US"
  ) -> str:
      """Performs a web search using the Bing Search API for general information
      and websites.
  
      Args:
          query: Search query (required)
          count: Number of results (1-50, default 10)
          offset: Pagination offset (default 0)
          market: Market code like en-US, en-GB, etc.
      """
      # Get API key from environment
      api_key = os.environ.get("BING_API_KEY", "")
  
      if not api_key:
          return (
              "Error: Bing API key is not configured. Please set the "
              "BING_API_KEY environment variable."
          )
  
      try:
          check_rate_limit()
  
          headers = {
              "User-Agent": USER_AGENT,
              "Ocp-Apim-Subscription-Key": api_key,
              "Accept": "application/json",
          }
  
          params = {
              "q": query,
              "count": min(count, 50),  # Bing limits to 50 results max
              "offset": offset,
              "mkt": market,
              "responseFilter": "Webpages",
          }
  
          search_url = f"{BING_API_URL}v7.0/search"
  
          async with httpx.AsyncClient() as client:
              response = await client.get(
                  search_url, headers=headers, params=params, timeout=10.0
              )
  
              response.raise_for_status()
              data = response.json()
  
              if "webPages" not in data:
                  return "No results found."
  
              results = []
              for result in data["webPages"]["value"]:
                  results.append(
                      f"Title: {result['name']}\n"
                      f"URL: {result['url']}\n"
                      f"Description: {result['snippet']}"
                  )
  
              return "\n\n".join(results)
  
      except httpx.HTTPError as e:
          return f"Error communicating with Bing API: {str(e)}"
      except Exception as e:
          return f"Unexpected error: {str(e)}"

• mcp_server_bing/server.py:77-92 (helper)

  Helper function for rate limiting, called within bing_web_search to enforce API usage limits.

  def check_rate_limit():
      """Check if we're within rate limits"""
      now = time.time()
      if now - request_count["last_reset"] > 1:
          request_count["second"] = 0
          request_count["last_reset"] = now
  
      if (
          request_count["second"] >= RATE_LIMIT["per_second"]
          or request_count["month"] >= RATE_LIMIT["per_month"]
      ):
          raise Exception("Rate limit exceeded")
  
      request_count["second"] += 1
      request_count["month"] += 1

• mcp_server_bing/server.py:94-94 (registration)

  The @server.tool() decorator registers the bing_web_search function as an MCP tool.

  @server.tool()