* With the exception of {{tl|cmd}}, {{tl|gen}} and {{tl|todo}}, you cannot use wiki templates. Wiki templates can change over time, and that would create a nasty external dependency.
* The <code><nowiki></code> tag is '''forbidden''' anywhere within a Command page.
* As is <code><syntax></code>. Use {{tl|cmd}} or {{tl|gen}} to refer to other commands.
* Don't use regular HTML tags except for <code><b></code>, <code><i></code>, <code><tt></code>, <code><nowiki><pre></nowiki></code> and <code><nowiki><code></nowiki></code>. '''As noted above:''' even the content of <code><pre></code> and <code><code></code> must be properly quoted according to the XML rules: use XML entities for less-than, greater-than and ampersand: <code>&lt;</code>, <code>&gt;</code> and <code>&amp;</code>
* You don't have to quote the XML special characters inside the text content of the <code><nowiki><texcode></nowiki></code>, <code><nowiki><xmlcode></nowiki></code>, and <code><nowiki><context></nowiki></code> tags. These three are handled as special cases to make porting existing pages easier ([[Extension:ConTeXtXML#Implementation notes]] explains this in more detail).