Kroger MCP Server

Instructions

    Get a list of all Kroger-owned chains.
    
    Returns:
        Dictionary containing chain information
    

Implementation Reference

• src/kroger_mcp/tools/info_tools.py:15-62 (handler)

  The main handler function for the 'list_chains' tool. It retrieves the list of Kroger chains using the client API, formats the data, provides context feedback, handles errors, and returns a structured dictionary.

  async def list_chains(ctx: Context = None) -> Dict[str, Any]:
      """
      Get a list of all Kroger-owned chains.
      
      Returns:
          Dictionary containing chain information
      """
      if ctx:
          await ctx.info("Getting list of Kroger chains")
      
      client = get_client_credentials_client()
      
      try:
          chains = client.location.list_chains()
          
          if not chains or "data" not in chains or not chains["data"]:
              return {
                  "success": False,
                  "message": "No chains found",
                  "data": []
              }
          
          # Format chain data
          formatted_chains = [
              {
                  "name": chain.get("name"),
                  "division_numbers": chain.get("divisionNumbers", [])
              }
              for chain in chains["data"]
          ]
          
          if ctx:
              await ctx.info(f"Found {len(formatted_chains)} chains")
          
          return {
              "success": True,
              "count": len(formatted_chains),
              "data": formatted_chains
          }
          
      except Exception as e:
          if ctx:
              await ctx.error(f"Error listing chains: {str(e)}")
          return {
              "success": False,
              "error": str(e),
              "data": []
          }

• src/kroger_mcp/server.py:72-78 (registration)

  Registration block in the server creation where info_tools.register_tools(mcp) is called at line 75, registering the list_chains tool along with others.

  location_tools.register_tools(mcp)
  product_tools.register_tools(mcp)
  cart_tools.register_tools(mcp)
  info_tools.register_tools(mcp)
  profile_tools.register_tools(mcp)
  utility_tools.register_tools(mcp)
  auth_tools.register_tools(mcp)

• src/kroger_mcp/tools/shared.py:25-53 (helper)

  Helper function used by list_chains to obtain a KrogerAPI client with client credentials for accessing public location data.

  def get_client_credentials_client() -> KrogerAPI:
      """Get or create a client credentials authenticated client for public data"""
      global _client_credentials_client
      
      if _client_credentials_client is not None and _client_credentials_client.test_current_token():
          return _client_credentials_client
      
      _client_credentials_client = None
      
      try:
          load_and_validate_env(["KROGER_CLIENT_ID", "KROGER_CLIENT_SECRET"])
          _client_credentials_client = KrogerAPI()
          
          # Try to load existing token first
          token_file = ".kroger_token_client_product.compact.json"
          token_info = load_token(token_file)
          
          if token_info:
              # Test if the token is still valid
              _client_credentials_client.client.token_info = token_info
              if _client_credentials_client.test_current_token():
                  # Token is valid, use it
                  return _client_credentials_client
          
          # Token is invalid or not found, get a new one
          token_info = _client_credentials_client.authorization.get_token_with_client_credentials("product.compact")
          return _client_credentials_client
      except Exception as e:
          raise Exception(f"Failed to get client credentials: {str(e)}")