kunalb

<ul>
<li>Call <code>kb_debug</code> with any arguments that you want to log and they will be pretty printed at the end of the document.</li>
<li>To log and show a list of all warnings, errors and notices generated by your plugin, add <code>?KB_Debug_Errors</code> to your URL. </li>
<li>To see a list of all hooks in the order they fire as well as what arguments they are called with and what functions run on them (again, in which order), 
add a <code>?KB_Debug_Hooks</code> to the URL.</li>
</ul>
To see both just add ?KB_Debug_Errors&KB_Debug_Hooks. (Essentially $_GET[var] must be set to enable that feature).
<h3>Features</h3>
<ul>
<li>Logs and displays all warnings, errors, etc. alongwith their context.</li>
<li>Logs and displays all hooks alongwith the argument(s) each hook is called with and the functions that run on that particular hook (in order).</li>
</ul>

kb_debug.php

Greg Winiarski

BlackBox is symfony like unobstrusive debug bar attached to the top of the browser window.
How can it help you with development: 
1. instantly inspect global variables (GET, POST, COOKIE, SERVER) 
2. debug both frontend and admin area 
3. executed MySQL queries and time it took to execute each query (useful for finding slow queries) 
4. profiler for measuring performance of your plugins and themes 
5. errors occurred when loading WordPress page

BlackBox Debug Bar

Immediate feedback on a great majority of errors. Added a conditional red background to the Errors, and with this modification I have never miss even a notice anymore.

Thank you very much!

Essential plugin in my developer toolset

BlackBox is a plugin for plugin and theme developers. It collects and displays useful debug information (errors, executed queries, globals, profiler).

kb_debug.php vs BlackBox Debug Bar