Google’s undocumented, unpublished, not-for-public-consumption Spell Check API stopped working. How dare they? Well turns out the fix is simple, after using Charles to debug the HTTP requests of the Google Toolbar spell checker, I narrowed down the difference between my calls and theirs to a missing host header. Added that back in and everything works again. Usage: (I don’t parse the XML, because I’m just passing it to a flash client): [sourcecode language=”ruby”] => puts Spell.check(‘does it worka?’) <?xml version="1.0" encoding="UTF-8"?><spellresult error="0" clipped="0" charschecked="14"><c o="8" l="5" s="1">works work wok worker woke</c></spellresult> [/sourcecode] Source: [sourcecode language=”ruby”] require ‘rubygems’ require ‘builder’ require ‘net/http’ require ‘net/https’ module Spell HOST_HEADER = ‘www.google.com’ HOST_POST = ‘google.com’ PATH = "/tbproxy/spell?lang=en&hl=en&v=2.0f" def self.check(text) http = Net::HTTP.new(HOST_POST,443) http.use_ssl = true http.verify_mode = OpenSSL::SSL::VERIFY_NONE headers = {"Host" => HOST_HEADER} data = get_xml_payload(text) response_headers, response_data = http.post(PATH, data, headers) response_data end private def self.get_xml_payload(text) xml = Builder::XmlMarkup.new xml_string = xml.spellrequest(:textalreadyclipped => "0", :ignoredups => "0", :ignoredigits => "1", :ignoreallcaps => "0") do xml.text(text) end end end [/sourcecode]