Better sublime text 3 intellitip extension (replace py in packages). Gives function description and syntax on hover.

intellitip.py

import sublime_plugin, sublime, json, webbrowser
import re, os
from time import time

settings = {}

class IntellitipCommand(sublime_plugin.EventListener):

    cache = {}
    region_row = []
    lang = None
    completions = []

    def on_activated(self, view):
        Pref.time = time()
        sublime.set_timeout(lambda:self.run(view, 'activated'), 0)

    def on_modified(self, view):
        Pref.time = time()

    def on_selection_modified(self, view):
        now = time()
        sublime.set_timeout(lambda:self.run(view, 'selection_modified'), 0)
        Pref.time = now

    def on_activated(self, view):
        global lang, completions  
        lang = self.getLang(view)
        print(lang)
        if lang not in self.cache: #DEBUG disable cache: or 1 == 1
            path_db = os.path.dirname(os.path.abspath(__file__))+"/db/%s.json" % lang
            self.debug("Loaded intelliDocs db:", path_db)

            if os.path.exists(path_db):
                self.cache[lang] = json.load(open(path_db))
            else:
                self.cache[lang] = {}

        completions = self.cache[lang]

    def on_hover(self, view, point, hover_zone):
        global completions
        if(hover_zone == 1):
            region = view.word(point)
            word = view.substr(region)
            found = completions.get(word)

            if found:
                menus = ['<style>%s</style>' % Pref.css]

                menus.append("<i>%s</i><br>" % found["syntax"])

                for descr in re.sub("(.{100,120}[\.]) ", "\\1||", found["descr"]).split("||"): #Spit long description lines
                    menus.append("<br>"+descr+"<br>")

                if found["params"]:
                    menus.append("<h3>Parameters:</h3>")

                for parameter in found["params"]:
                    menus.append("- <b>"+parameter["name"]+":</b> "+parameter["descr"]+"<br>")

                if found["path"]:
                    menus.append("<br><small>Defined in %s</small><br>" % found["path"])

                menus.append("Type: <small>%s</small>" % found["type"])

                self.appendLinks(menus, found)

                view.show_popup(''.join(menus), location=region.a, max_width=600, on_navigate=self.on_navigate)
            else:
                view.hide_popup()
        
    def run(self, view, where):
        global region_row, lang

        view_settings = view.settings()
        if view_settings.get('is_widget'):
            return

        for region in view.sel():
            region_row, region_col = view.rowcol(region.begin())

            if region_row != view_settings.get('intellitip_row', -1):
                view_settings.set('intellitip_row', region_row)
            else:
                return

    def appendLinks(self, menus, found):
        for pattern, link in sorted(Pref.help_links.items()):
            if re.match(pattern, found["path"]):
                host = re.match(".*?//(.*?)/", link).group(1)
                #menus.append('<br>Open docs: <a href="%s">Docs</a>' % found["name"])
                break
        return menus

    def getLang(self, view):
        scope = view.scope_name(view.sel()[0].b) #try to match against the current scope

        for match, lang in Pref.docs.items():
            if re.match(".*"+match, scope): return lang
        return re.match(".*/(.*?).sublime-syntax", view.settings().get("syntax")).group(1) #no match in predefined docs, return from syntax filename

    def getFunctionNames(self, view, completions):
        global region_row
        return [view.substr(view.word(view.sel()[0]))]

    def on_navigate(self, link):
        global lang
        webbrowser.open_new_tab(Pref.help_links[lang.lower()] % link)

    def debug(self, *text):
        if Pref.debug:
            print(*text)

def init_css():
    css_file = 'Packages/' + Pref.css_file

    try:
        Pref.css = sublime.load_resource(css_file).replace('\r', '')
    except:
        Pref.css = None

    settings.clear_on_change('reload')
    settings.add_on_change('reload', 'init_css')

def plugin_loaded():
    global Pref, settings

    class Pref:
        def load(self):
            settings = sublime.load_settings("intellitip.sublime-settings")
            Pref.wait_time  = 0.12
            Pref.time       = time()
            Pref.css_file   = settings.get('css_file', "Intellitip/css/default.css")
            Pref.help_links = settings.get('help_links', [])
            Pref.docs       = settings.get('docs', None)
            Pref.debug      = settings.get('debug', False)
            Pref.css        = None
            if(Pref.docs != None):
                print("Intellitip Loaded successfully!")

    settings = sublime.load_settings("intellitip.sublime-settings")
    Pref = Pref()
    Pref.load()
    init_css()

    settings.add_on_change('reload', lambda:Pref.load())