Instead of fiddling into system internals, you may just map ^ERROR or better just the annoying part
to a different DB to see the impact. Then you clean up this one on a regular basis this DB,
Just Kill this branch. 
Or map it to IRISTEMP. It is cleaned at every restart.

THX.  Just verified it.

I fully support you.
Out of tradition, there is a tendency to implement already existing solutions though  better
and well-positioned on the markets. 
@Dmitry Maslennikov :
- you might remember times when even a webserver was written inside Caché
- or various text editors, source manager packages, and ..., and ... and ...
JUST because it was possible.
Decades back you had your globals and your language and not even an OS below.
But this was in previous millenium. This time is definitely over.
 

I missed this during a migration from Caché to IRIS.
There were roughly 1500 routines and ~2000 classes. grown over >15 years.
The point was to find out dependencies and estimate the impact of changes.
 

Thank you @Nigel Salm !

The buzzword "language"  distracted me.
In IRIS our good old ENSEMBLE was renamed to Interoperability and is there by default.
​​​​​@Heloisa Ramalho you should know it best and could give  a native explanation

Thanks!  

   docs sounds boring

@Dmitry Maslennikov 
Is this also supported by VSCode?

@Yuri Marx :
if you have the schema as XSD at hands 
All you need to do is to open the XML wizard in IRIS  Studio and it generates the whole packages for you

>>>

I used it rather intensive and a pack of 100+ classes from 1 XSD was no problem

I removed my example on PuTTY. 
It worked by mistake as the local firewall was switched off

If setup correctly it basically works as described by @Alexey Maslov 
and you need to log in separately on the server,
 

Correct.
After 20 years working with CSP since day 2.5 I just don't feel like discussing and explaining CSP internals anymore and argue against obviously wrong statements. 
There is enough public detailed documentation around .

Just post the class. 

the generated file:
------------------------------------------------------------------------------------------
<br><p>
<nobr>Klasse <b>zrcc.EX.ISOS</b>
</nobr><p>Execute InterSystems ObjectScript over ODBC</p><a name="Anchor_Inventory"></a>
<table class="Label" cellpadding="0" cellspacing="0" cols="1">
<tr valign="center">
<td align="left" width="100%" >
<a href="#" onclick="expandIt(1); return false;" class="PackageChoice" title="Expand/Collapse Inventory" onmouseover="this.style.color = 'red';" onmouseout="this.style.color = 'black';">
    <image id=Im1 src=/csp/sys/images/ExpandedMarker.jpg height=15 width=16 border=0 align=bottom>
<nobr><b>Inventory</b></nobr></a>
</td>
</tr>
</table>
<br>
<div id="Id1" class="DivShow" style="">
<table class="Summary" cellpadding="0" cellspacing="0" cols="1">
<tr valign="center">
<th align="center">
Parameters
</th>
<th align="center">
Properties
</th>
<th align="center">
<a href="#Anchor_Methods">Methods</a>
</th>
<th align="center">
Queries
</th>
<th align="center">
Indices
</th>
<th align="center">
ForeignKeys
</th>
<th align="center">
Triggers
</th>
</tr>
<tr>
<td align="center" class="private">
</td>
<td align="center" class="private">
</td>
<td align="center">
<a href="#Anchor_Methods">3</a>
</td>
<td align="center" class="private">
</td>
<td align="center" class="private">
</td>
<td align="center" class="private">
</td>
<td align="center" class="private">
</td>
</tr>
</table>
<br/>
<br/></div>
<a name="Anchor_Summary"></a>
<table class="Label" cellpadding="0" cellspacing="0" cols="1">
<tr valign="center">
<td align="left" width="100%" >
<a href="#" onclick="expandIt(2); return false;" class="PackageChoice" title="Expand/Collapse Summary" onmouseover="this.style.color = 'red';" onmouseout="this.style.color = 'black';">
    <image id=Im2 src=/csp/sys/images/ExpandedMarker.jpg height=15 width=16 border=0 align=bottom>
<nobr><b>Summary</b></nobr></a>
</td>
</tr>
</table>
<br>
<div id="Id2" class="DivShow" style="">
<table class="Summary" border="0" cellspacing="0" cellpadding="1">
        <tr><th colspan="3" title="Bold for local member; italics for inherited; shaded for private; blue for client methods; strikethrough for deprecated.">Methoden</th></tr>
<tr>
<td  nowrap><a class="" href="#METHOD_Gset" title="zrcc.EX.ISOS">Gset</a></td>
<td  nowrap><a class="" href="#METHOD_Ping" title="zrcc.EX.ISOS">Ping</a></td>
<td  nowrap><a class="" href="#METHOD_Xcmd" title="zrcc.EX.ISOS">Xcmd</a></td>
</tr>
</table><br/>
<br/></div>
<a name="Anchor_Methods"></a>
<table class="Label" cellpadding="0" cellspacing="0" cols="1">
<tr valign="center">
<td align="left" width="100%" >
<a href="#" onclick="expandIt(3); return false;" class="PackageChoice" title="Expand/Collapse Methods" onmouseover="this.style.color = 'red';" onmouseout="this.style.color = 'black';">
    <image id=Im3 src=/csp/sys/images/ExpandedMarker.jpg height=15 width=16 border=0 align=bottom>
<nobr><b>Methods</b></nobr></a>
</td>
</tr>
</table>
<br>
<div id="Id3" class="DivShow" style="">
<a name="Gset"></a>
<a name="METHOD_Gset"></a>
<span class="external"><nobr>&#149 classMethode <b>Gset(glob As <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr>, subs As <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr>, val As <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr> = "", dd As <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25Integer">%Integer</a></nobr> = 1)</b>
as <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr></nobr>
[ SQLProc = Gset ]</span><blockquote>
set / kill global over ODBC
subs = subscript in ( )
dd = $data of source during global copy</blockquote>
<a name="Ping"></a>
<a name="METHOD_Ping"></a>
<span class="external"><nobr>&#149 classMethode <b>Ping()</b>
as <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr></nobr>
[ SQLProc = Ping ]</span><blockquote>
check connectivity</blockquote>
<a name="Xcmd"></a>
<a name="METHOD_Xcmd"></a>
<span class="external"><nobr>&#149 classMethode <b>Xcmd(cmd As <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr>, ret As <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr> = "")</b>
as <nobr><a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a></nobr></nobr>
[ SQLProc = Xcmd ]</span><blockquote>
eXecute Command over ODBC
name of local variable for return value</blockquote>
-------------------------------------------------------------------------------------------
​​​

Hi @Yuri Marx!
I did a quick and dirty try during lunch in terminal:   

set %library=$namespace
set set %request=##class(%CSP.Request).%New()
set cdef=##class(%ClassDefinition).%OpenId("zrcc.EX.ISOS")     ; my classname
set file="my.html" o file:("WNS"):0 write $t     ;  1 if OK
use file d ##class(%CSP.Documatic).RenderClassPage(cdef,1)
close file

The result still holds references to /csp/...images  and data types  
     <image id=Im1 src=/csp/sys/images/ExpandedMarker.jpg height=. . . 
    <a href="%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=USER&CLASSNAME=%25String">%String</a>
that you might want to resolve as they are quite generic or you just ignore it .
My browser is very friendly  :-)
And that's the result:

Some polishing might be required