get_field_options

Instructions

    Get available options for a Link or Select field.
    
    For Link fields, returns documents from the linked DocType.
    For Select fields, returns the predefined options.
    
    Args:
        doctype: DocType name
        fieldname: Field name
        limit: Maximum number of options to return (default: 20)
    

Implementation Reference

• src/tools/schema.py:95-164 (handler)

  The main handler function implementing the get_field_options tool. It fetches the DocType schema, identifies the field type (Link or Select), and retrieves either linked documents or static options.

  async def get_field_options(
      doctype: str,
      fieldname: str,
      limit: Optional[int] = 20
  ) -> str:
      """
      Get available options for a Link or Select field.
      
      For Link fields, returns documents from the linked DocType.
      For Select fields, returns the predefined options.
      
      Args:
          doctype: DocType name
          fieldname: Field name
          limit: Maximum number of options to return (default: 20)
      """
      try:
          client = get_client()
          
          # First get the field definition to understand its type
          schema_response = await client.get(f"api/resource/DocType/{doctype}")
          
          if "data" not in schema_response:
              return f"Could not get schema for DocType: {doctype}"
          
          fields = schema_response["data"].get("fields", [])
          target_field = None
          
          for field in fields:
              if field.get("fieldname") == fieldname:
                  target_field = field
                  break
          
          if not target_field:
              return f"Field '{fieldname}' not found in DocType '{doctype}'"
          
          fieldtype = target_field.get("fieldtype")
          options = target_field.get("options", "")
          
          if fieldtype == "Link":
              # Get documents from linked DocType
              if not options:
                  return f"Link field '{fieldname}' has no linked DocType defined"
              
              params = {
                  "fields": json.dumps(["name", "title"]),
                  "limit": str(limit)
              }
              
              response = await client.get(f"api/resource/{options}", params=params)
              
              if "data" in response:
                  documents = response["data"]
                  return f"Available {options} documents for field '{fieldname}':\n\n" + json.dumps(documents, indent=2)
              else:
                  return json.dumps(response, indent=2)
          
          elif fieldtype == "Select":
              # Parse select options
              if not options:
                  return f"Select field '{fieldname}' has no options defined"
              
              select_options = [opt.strip() for opt in options.split("\n") if opt.strip()]
              return f"Select options for field '{fieldname}':\n\n" + json.dumps(select_options, indent=2)
          
          else:
              return f"Field '{fieldname}' is of type '{fieldtype}' which doesn't have predefined options"
              
      except Exception as error:
          return _format_error_response(error, "get_field_options")

• src/server.py:41-41 (registration)

  Registers the schema tools module, which includes the get_field_options tool, with the MCP server instance.

  schema.register_tools(mcp)

• src/tools/schema.py:15-33 (helper)

  Utility function used by get_field_options (and other tools) to format and return detailed error responses.

  def _format_error_response(error: Exception, operation: str) -> str:
      """Format error response with detailed information."""
      credentials_check = validate_api_credentials()
      
      # Check for missing credentials first
      if not credentials_check["valid"]:
          error_msg = f"Authentication failed: {credentials_check['message']}. "
          error_msg += "API key/secret is the only supported authentication method."
          return error_msg
      
      # Handle FrappeApiError
      if isinstance(error, FrappeApiError):
          error_msg = f"Frappe API error: {error}"
          if error.status_code in (401, 403):
              error_msg += " Please check your API key and secret."
          return error_msg
      
      # Default error handling
      return f"Error in {operation}: {str(error)}"

• src/server.py:38-42 (registration)

  Block where all tools are registered during server creation, specifically including schema tools containing get_field_options.

  # Register all tool modules
  helpers.register_tools(mcp)
  documents.register_tools(mcp)
  schema.register_tools(mcp)
  reports.register_tools(mcp)